Battery cooling device for vehicle use

Abstract

The air suction mode can be switched among the inside air mode in which the air sucked by the battery cooling blower 15 to cool the battery 3 for vehicle use is the air inside a vehicle passenger compartment, the outside air mode in which the air sucked by the battery cooling blower 15 is the air outside the vehicle passenger compartment and the cooling air mode in which the air sucked by the battery cooling blower 15 is the air cooled by an evaporator of the rear seat side air conditioner 2.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a battery cooling device for vehicle use. More particularly, the present invention relates to a battery cooling device, for vehicle use, for cooling a battery mounted on a vehicle provided with an air conditioner.

2. Description of the Related Art

Conventionally, in a battery cooling device, for vehicle use, for cooling a battery which is mounted on a hybrid powered automobile or electric automobile, the battery is cooled when a flow of air sucked from a vehicle passenger compartment is blown to the battery by a battery cooling blower. From the viewpoints of prolonging the battery life and ensuring safety, the volume of air blown out by the battery cooling blower is changed according to the temperature of the battery so that the temperature of the battery is maintained at about 40° C.

Further, a battery cooling device has been disclosed which is capable of cooling a battery without being greatly affected by disturbance such as sunshine or heat emitted from an exhaust gas pipe. For example, this battery cooling device is disclosed in the official gazette of JP-A-2004-255960. According to the Patent Document, the battery cooling device includes: an inside air blowing mode in which the air inside a vehicle passenger compartment is sucked and blown to the battery; and an outside air blowing mode in which the air outside the vehicle passenger compartment is sucked and blown to the battery. This battery cooling device further includes a cooling means for cooling the air to be blown to the battery during the inside air blowing mode period.

However, the battery cooling device described in the above Patent Document has an exclusive cooling means at, for example, an air inlet and other places. Therefore, the manufacturing cost is increased.

SUMMARY OF THE INVENTION

The present invention has been accomplished in view of the above circumstances. It is an object of the present invention to provide a battery cooling device, for vehicle use, capable of reducing the manufacturing cost.

Conventionally, various cooling systems for cooling a battery mounted on a hybrid powered automobile or an electric automobile have been devised. For example, a cooling system described in the official gazette of JP-A-2004-1674 is provided with a battery cooling blower. This battery cooling blower sucks a portion of the cooling air blown out from a blower used for air conditioning, and the thus sucked cooling air is blown to the battery so that the battery can be cooled.

However, according to the above battery cooling device, when a volume of air blown out from the battery cooling blower is changed, that is, when a volume of cooling air sucked by the battery cooling blower is changed, a volume of the conditioned air blown out to a passenger and a temperature of the conditioned air are changed. Due to the foregoing, the passenger feels uncomfortable. Therefore, it is an object of the present invention to provide an air conditioner for vehicle use characterized in that: even when a volume of the air blown out from the battery cooling blower is changed, a volume and temperature of the conditioned air which is blown out to the passenger are not changed.

In order to accomplish the above object, according to a first aspect of the present invention, there is provided a battery cooling device, cooling a battery for vehicle use, applied to a vehicle on which an air conditioner having a cooling means for cooling air passing through the cooling means is mounted, comprises: a battery cooling blower for blowing suction air to the battery for vehicle use; and a mode switching means capable of switching a mode among an inside air mode in which the suction air is the air inside a vehicle passenger compartment, an outside air mode in which the suction air is the air outside a vehicle passenger compartment and a cooling air mode in which the suction air is the air cooled by the cooling means of the air conditioner.

That is, the battery cooling device of the present invention includes an air inlet capable of taking in three types of air including the inside air, the outside air and the cooling air. In this case, the cooling air is the air cooled by the cooling means provided in the air conditioner. That is, without providing an exclusive cooling means,. it is possible to take in three types of air including the inside air, the outside air and the cooling air. According to this constitution, as no exclusive cooling means is provided, the manufacturing cost can be reduced.

In this connection, in the case where the battery for vehicle use is arranged at the rear of the vehicle, the above air conditioner may be an air conditioner for rear seat use. Due to the above structure, it becomes possible to decrease a distance in which the cooling air flows. Therefore, it is possible to reduce a heat loss to the cooling air.

In the second aspect of the present invention, the air outside the vehicle passenger compartment may be air in the trunk. As the trunk is located relatively distant from a passenger, it is difficult for the passenger to hear noise such as a sound of sucking air from the trunk. Accordingly, it is possible to prevent the passenger from feeling uncomfortable due to the sound of sucking air.

In the third aspect of the present invention, the mode switching means may switch the mode in the order of the outside air mode, the inside air mode and the cooling air mode. When the priority is given in the order of the outside air mode, the inside air mode and the cooling air mode, it becomes possible to save energy as follows. The sucked air in the cooling air mode is air cooled by the cooling means. As the cooling means is used in this case, the most energy is consumed in this case. The sucked air in the inside air mode is air which has been conditioned. This conditioned air is generated by driving the air conditioner in many cases. That is, in the inside air mode, energy is also consumed for driving the air conditioner although the energy consumption is not higher than that of the cooling air mode. The sucked air in the outside air mode is the outside air itself, therefore, no energy is consumed in this outside air mode. Accordingly, when the mode switching means switches the mode in the above order, the energy consumption can be reduced.

According to a fourth aspect of the present invention, the mode switching means may switch a mode in the order of the outside air mode, the inside air mode and the cooling air mode according to the temperature of the battery for vehicle use in the case where the temperature outside the vehicle passenger compartment is not more than a predetermined value, and the mode switching means may switch a mode in the order of the inside air mode and the cooling air mode according to the temperature of the battery for vehicle use in the case where the temperature outside the vehicle passenger compartment is higher than the predetermined value.

In the case where the temperature of the air outside the vehicle passenger compartment is not higher than a predetermined value, operation is started from the outside air mode. In the case where the temperature of the air outside the vehicle passenger compartment is higher than the predetermined value, operation is started from the inside air mode. For example, in the case where the predetermined value is 30° C., as it is necessary to maintain the temperature of the battery for vehicle use at about 40° C., the battery for vehicle use can be cooled by the outside air when the temperature of the air outside the vehicle passenger compartment is not higher than the predetermined temperature. That is, in the case where the temperature of the air outside the vehicle passenger compartment is not higher than the predetermined value, the outside air mode, in which the energy consumption is the lowest, is utilized. On the other hand, in the case where the temperature of the air outside the vehicle passenger compartment is higher than the predetermined value, it is impossible to use the air outside the vehicle passenger compartment for cooling the battery for vehicle use. Therefore, when operation is started from the inside air mode without using the outside air mode from the beginning, it is possible to prevent blowing the air outside the vehicle passenger compartment, the temperature of which is relatively high, to the battery for vehicle use.

In the fifth aspect of the present invention, the mode switching means may switch the mode among the inside. air mode, the outside air mode and the cooling air mode according to the temperature of the outside the vehicle passenger compartment and the temperature of the battery for vehicle use. Due to the foregoing, the air, the temperature of which is an appropriate value, can be blown to the battery for vehicle use.

In the sixth aspect of the present invention, the air conditioner mounted in the vehicle may be a front seat side air conditioner arranged on the front seat side of the vehicle and a rear seat side air conditioner arranged on the rear seat side of the vehicle, and the cooling air mode may be a mode in which the sucked air is cooled by the cooling means of the rear seat side air conditioner of the vehicle. In the cooling air mode, when air is cooled by the cooling means of the rear seat side air conditioner of the vehicle, air conditioning in the vehicle passenger compartment can be positively conducted by the front seat side air conditioner of the vehicle. Accordingly, a passenger does not have a feeling of discomfort, and the vehicle battery can be positively cooled. Naturally, the above cooling mode may be a mode in which the above sucked air is air which has been cooled by the cooling means of the front seat side air conditioner of the vehicle.

According to a seventh aspect of the present invention, a battery cooling device cooling a battery for vehicle use, applied to a vehicle on which an air conditioner having a cooling means for cooling air passing through the cooling means is mounted, may comprise: a battery cooling blower for blowing suction air to the battery for vehicle use; and a mode selecting means for selecting a suction mode of the battery cooling blower between the inside air mode, in which the air in the vehicle passenger compartment is sucked, and the cooling air mode in which the air immediately after it is cooled by the cooling means is sucked.

That is, the battery cooling device has an air inlet capable of taking in two types of air of the inside air and the cooling air, and the cooling air is the air cooled by the cooling means of the air conditioner. Due to the foregoing, it is unnecessary to provide an exclusive cooling means, and two types of air of the inside air and the cooling air can be positively taken in. As no exclusive cooling means is provided, the manufacturing cost can be reduced.

In this case, in the cooling air mode, the sucked air to be blown to the battery is cooled by the cooling means of the air conditioner. Therefore, the cooling capacity of cooling the battery is higher than that of the inside air mode. On the other hand, when the temperature of the air outside the vehicle is extremely low, for example, when the temperature of the air outside the vehicle is not higher than 0° C., it becomes impossible to operate the refrigerating cycle composing the air conditioner. Therefore, it becomes impossible to cool the sucked air with the cooling means.

According to an eighth aspect of the present invention, a battery cooling device for vehicle use, may further comprise: an outside air temperature detection means for detecting a temperature outside the vehicle; and a battery temperature detection means for detecting a temperature of the battery, wherein the mode selecting means may select a suction mode between the inside air mode and the cooling air mode according to the temperature of the air outside the vehicle detected by the outside air temperature detection means and also according to the temperature of the battery detected by the battery temperature detection means. Moreover, according to a ninth aspect of the present invention, the mode selecting means may select a suction mode between the inside air mode and the cooling air mode according to the temperature of the battery in the case where the temperature of the air outside the vehicle is higher than. a predetermined temperature, and the mode selecting means may select the inside air mode in the case where the temperature of the air outside the vehicle is not more than the predetermined temperature.

When the temperature of the air outside the vehicle is low, the temperature in the vehicle passenger compartment is relatively low in many cases. Therefore, in the case where the temperature of the air outside the vehicle is higher than the predetermined temperature, when the battery temperature is lower than the reference temperature, the inside air mode is selected. When the battery temperature is not lower than the reference temperature, the cooling air mode is selected. When the temperature of the air outside the vehicle is raised, the reference temperature is decreased. Due to the foregoing, the frequency of using the cooling air mode, the energy consumption of which is large, can be reduced and energy can be saved.

According to a twelfth aspect of the present invention, the mode selecting means may select a mode in which the air in the vehicle passenger compartment is sucked together with the air immediately after it is cooled by the cooling means at the time of the cooling air mode.

Air cooled by the cooling means is originally used for air-conditioning the vehicle passenger compartment. However, at the time of cooling air mode, a portion of the cooled air is used for cooling the battery. Therefore, when a large volume of cooling air is used for the battery, a feeling of air conditioning the vehicle passenger compartment is deteriorated. Therefore, at the time of the cooling air mode, when the air in the vehicle passenger compartment of the vehicle is sucked together with the air immediately after the air has been cooled by the cooling means, it is possible to increase a volume of air used for cooling the battery without deteriorating a feeling of air-conditioning in the vehicle passenger compartment.

According to a thirteenth aspect of the present invention, a battery cooling device cooling a battery for vehicle use is applied to a vehicle on which an air conditioner having a cooling means for cooling air passing through the cooling means is mounted, may comprise: a battery cooling blower for blowing suction air to the battery for vehicle use; and a mode selecting means for selecting a suction mode of the battery cooling blower among the inside air mode, in which the air in the vehicle passenger compartment is sucked, the cooling air mode, in which the air immediately after it is cooled by the cooling means is sucked, and a mixed air mode in which both the air in the vehicle passenger compartment and the air immediately after it is cooled by the cooling means are sucked.

That is, the battery cooling device includes an air inlet opening capable of taking in three types of air including the inside air, the cooling air and the mixed air in which the inside air and the cooling air are mixed with each other, and the cooling air is air cooled by the cooling means of the air conditioner. Due to the foregoing, two types of air of the inside air and the cooling air can be positively taken in without providing an exclusive cooling means. As no exclusive cooling means is provided as described above, the manufacturing cost can be reduced.

As described above, the battery cooling capacity of the cooling air mode is higher than that of the inside air mode. On the other hand, in the case where the temperature of the air outside the vehicle is extremely low, it becomes impossible to cool the sucked air with the cooling means of the air conditioner for vehicle use. According to a fourteenth aspect of the present invention, a battery cooling device for vehicle use, may further comprise: an outside temperature detection means for detecting the temperature of the air outside the vehicle; and a battery temperature detection means for detecting the battery temperature, wherein the mode selecting means may select a suction mode among the inside air mode, the cooling air mode and the mixed air mode according to the temperature of the air outside the vehicle detected by the outside air temperature detection means and also according to the temperature of the battery detected by the battery temperature detection means. Moreover, according to a fifteenth aspect of the present invention, the mode selecting means may select a suction mode among the inside air mode, the cooling air mode and the mixed air mode according to the temperature of the battery in the case where the temperature of the air outside the vehicle is higher than a predetermined temperature, and the mode selecting means may select the inside air mode in the case where the temperature of the air outside the vehicle is not more than the predetermined temperature.

As described above, when the temperature of the air outside the vehicle is low, the temperature in the vehicle passenger compartment is relatively low in many cases. Therefore, in the case where the temperature of the air outside the vehicle is higher than the predetermined temperature, when the battery temperature is lower than the first reference temperature, the inside air mode is selected. When the battery temperature is not lower than the first reference temperature and lower than the second reference temperature, the cooling air mode is selected. When the battery temperature is not lower than the second reference temperature, the mixed air mode is selected. When the temperature of the air outside the vehicle is raised, at least one of the first and the second reference temperature is decreased or both the first and the second reference temperature are decreased. Due to the foregoing, the frequency of using the cooling air mode, the energy consumption of which is large, can be reduced and energy can be saved.

According to an eighteenth aspect of the present invention, an air conditioner for vehicle use comprises: an air-conditioning unit, a battery cooling unit, and a control unit. The air-conditioning unit includes a cooling air generation means for generating cooling air by cooling the passing air, a heating air generation means for generating heating air by heating the passing air, a conditioned air generation means for generating conditioned air by mixing the cooling air and the heating air by a ratio of the hot air to the cold air, and an air-conditioning blower for generating conditioned blowout air blowing out to a passenger in a vehicle passenger compartment.

The battery cooling unit includes a battery cooling blower, which sucks the cooling air, for generating a flow of battery cooling air to be blown out to a battery mounted on a vehicle. The control unit includes a conditioned air ratio calculating means for calculating a ratio of the hot air to the cold air, a correction means for correcting at least one of the ratio of the hot air to the cold air and the conditioned air volume level according to the battery cooling air volume level, a conditioned air volume level control means for controlling a conditioned air volume level which is the air volume level of the conditioned air blown out, and a battery air volume level control means for controlling a battery cooling air volume level which is an air volume level of the battery cooling air blown out.

According to a twenty-first aspect of the present invention, an air conditioner for vehicle use comprises: an air-conditioning unit, a battery cooling unit, and a control unit. The air-conditioning unit includes a cooling air generation means for generating cooling air by cooling the passing air, a heating air generation means for generating heating air by heating the passing air, a conditioned air generation means for generating conditioned air by mixing the cooling air and the heating air by a ratio of the hot air to the cold air, an air-conditioning blower for generating conditioned blowout air blowing out to a passenger in a vehicle passenger compartment, and a conditioned air blowout temperature detection means for detecting a conditioned air blowout temperature which is a temperature of the conditioned blowout air.

The battery cooling unit includes: a battery cooling blower for generating a flow of battery cooling air, which is blown to the battery mounted on the vehicle, from the sucked air; and a mode switching means for switching the mode between the inside air mode, in which the sucked air is made to be the inside air in the vehicle passenger compartment according to the battery temperature, and the cooling air mode in which the sucked air is made to be the cooling air.

The control means includes: a conditioned air ratio calculating means for calculating a ratio of the hot air to cold air; a conditioned air volume level control means for controlling a conditioned air volume level which is a level of the volume of conditioner air to be blown out; and a battery air volume level control means for controlling a battery cooling air volume level which is a volume level of cooling air to be blown to the battery.

Further, the battery air volume level control means decreases the battery cooling air volume level to a value not higher than a predetermined value at the time of switching the mode and further decreases a rate of change in the battery cooling air volume in the case where a rate of change in the conditioned air blowing temperature exceeds a predetermined value.

In this case, in the eighteenth and twenty-first aspect, the conditioned air generating means of the air conditioner for vehicle use is a means for generating the conditioned air by which the temperature in the vehicle passenger compartment air-conditioned zone is made to be a temperature, which has been set by a passenger, by mixing the cooling air with the heated air, the temperature of which is higher than that of the cooling air.

The battery air volume level control means controls a battery cooling blower so that the battery cooling air volume level can be raised in the case where the battery temperature is high. Due to the foregoing, for example, the temperature of a superheated battery for vehicle use can be quickly lowered. On the contrary, in the case where the battery temperature is low, the battery air volume level control means controls the battery cooling blower so that the battery cooling air volume level can be lowered. Due to the foregoing, the battery temperature can be maintained at an appropriate value.

In the eighteenth aspect, the following effects can be provided by one correcting means provided in the air conditioner for vehicle use. In this case, the correcting means for correcting a ratio of the hot air to the cold air according to the battery cooling air volume level corrects the ratio of the hot air to the cold air so that the air conditioning blowing temperature, which is changed according to a change in the battery cooling air volume level, can be maintained constant. The correcting means for correcting a ratio of the hot air to the cold air according to the battery cooling air volume level will be referred to as the hot air to the cold air ratio correcting means in this specification, hereinafter. For example, in the case where the battery cooling air volume level is increased, that is, in the case where the suction volume of the cooling air blown out by the battery cooling blower is increased, a ratio of the cooling air contained in the conditioned air is decreased. Then, the temperature of the conditioned air blown out into the air-conditioned zone in the vehicle passenger compartment is raised. Therefore, in order to replenish the cooling air, the hot air to the cold air ratio correcting means conducts correction so that a ratio of the cooling air in the conditioned air can be increased. Due to the foregoing, the temperature of the conditioned air to be blown out can be prevented from rising. On the other hand, in the case where the battery cooling air volume level is decreased, a ratio of the cooling air contained in the conditioned air is increased. Then, the temperature of the conditioned air blown out into the air-conditioned zone in the vehicle passenger compartment is lowered. Then, in order to reduce a volume of the cooling air, the hot and cold ratio correcting means conducts correction so that a ratio of the cooling air in the conditioned air can be decreased. Due to the foregoing, the temperature of the conditioned air to be blown out can be prevented from lowering. That is, the temperature of the conditioned air blown out can be maintained constant by the hot and cold ratio correcting means irrespective of a change in the battery cooling air volume level. Accordingly, the passenger can have a comfortable time in the vehicle passenger compartment without feeling unconfortable due to a change in the temperature of the conditioned air blown out.

In the eighteenth aspect, the following effects can be provided by the other correcting means provided in the air conditioner for vehicle use. In this case, the correcting means for correcting a conditioned air volume level according to the battery cooling air volume level is a means for correcting the conditioned air volume level so that a volume of the conditioned air blown out (a volume of air blown out to the passenger), which is going to change according to the change in the battery cooling air volume level, can be maintained constant. The correcting means for correcting a conditioned air volume level according to the battery cooling air volume level is referred to as an conditioned air volume level correcting means in this specification, hereinafter. For example, in the case where a battery cooling air volume level is increased, that is, in the case where a cooling air volume sucked by the battery cooling blower is increased, a volume of the conditioned air blown out is decreased. Therefore, in order to replenish the volume of the conditioned air blown out, the conditioned air volume level correcting means conducts a correction so that the conditioned air volume level can be increased, and a decrease in the volume of the conditioned air blown out can be suppressed. On the other hand, in the case where the battery cooling air volume level is decreased, the volume of the conditioned air blown out is increased. In order to decrease the volume of the conditioned air blown out, the conditioned air volume level correcting means conducts a correction so that the conditioned air volume level can be decreased. Due to the foregoing, an increase in the volume of the conditioned air blown out can be suppressed. That is, the conditioned air volume level correcting means maintains the volume of the conditioned air blown out irrespective of a change in the battery cooling air volume level. Accordingly, the passenger can have a comfortable time in the vehicle passenger compartment without feeling uncomfortable due to change in the temperature of the conditioned air blown out.

In the eighteenth aspect, when the air conditioner for vehicle use has one of the hot air to the cold air ratio correcting means and the conditioned air volume level correcting means, the effect can be respectively provided as described above. When the air conditioner for vehicle use has both the hot air to the cold air ratio correcting means and the conditioned air volume level correcting means, both effects can be provided.

In the twenty-first aspect, the mode switching means of the air conditioner for vehicle use switches the mode between the cooling air mode and the inside air mode according to the temperature of the battery for vehicle use. The suction air of the cooling air mode is the cooling air generated by the cooling air generating means. When this cooling air is blown out to the battery, it is possible to effectively cool the battery in a short period of time. On the other hand, the suction air of the inside air mode is the air in the vehicle passenger compartment. Different from the generation of the cooling air, the cooling generation means is not needed for the generation of this inside air. Accordingly, in the case of the inside air mode, it is possible to save energy compared with the cooling air mode. That is, according to the air conditioner for vehicle use of the twenty-first aspect, the mode switching means appropriately switches between the cooling air mode and the inside air mode. Therefore, the battery can be effectively cooled, and it becomes possible to save energy.

At the time of switching the mode, to be specific, at the time from the start of switching the mode to the completion of switching the mode, the battery air volume level control means reduces the battery cooling air volume level to a value not more than a predetermined value, and the level of noise generated at the time of switching the mode can be reduced. Naturally, the time of switching the mode is defined as both the time of switching the mode from the inside air mode to the cooling air mode by the mode switching means and the time of switching the mode from the cooling air mode to the inside air mode.

Further, the battery air volume level control means reduces a rate of the change in the battery cooling air volume level in the case where a rate of the change in. the temperature of the conditioned air blown out exceeds the predetermined value as described above. For example, the battery cooling air volume level, which has been reduced to a value not more than a predetermined value at the time of switching the mode from the inside air mode to the cooling air mode, is increased by the battery air volume level control means after the completion of switching. In other words, the cooling air suction volume of the battery cooling blower, which has been reduced to a value not more than a predetermined value at the time of switching the mode, is increased by the battery air volume level control means after the completion of switching. Due to the foregoing, a ratio of the cooling air contained in the conditioned air is decreased. That is, the temperature of the conditioned air blown out is raised. Further, the volume of the conditioned air blown out is decreased. In the case where a rate of the increase in the temperature of the conditioned air blown out and a rate of the decrease in the volume of the conditioned air blown out are low, the passenger hardly has a feeling of incongruity. However, in the case where a rate of the increase in the temperature of the conditioned air blown out and a rate of the decrease in the volume of the conditioned air blown out are high, the passenger has a feeling of incongruity. Therefore, in the case where a rate of the change in the temperature of the conditioned air blown out exceeds a predetermined value, when a rate of the change in the battery cooling air volume level is reduced, in the same manner as that of the effect of the eighteenth aspect, the passenger can have a comfortable time in the vehicle passenger compartment without feeling uncomfortable due to the change in the temperature of the air blown out and by the change in the volume of air blown out.

The battery air volume level control means described above may stop the battery cooling blower at the time of switching the mode. Due to the foregoing, the noise level, which tends to be caused at the time of switching the mode, can be positively reduced.

Further, the mode switching means may be composed so that the mode switching rate can be adjusted. In this case, the mode switching rate is defined as a period of time from the start of switching the mode to the completion of switching the mode. When the mode switching rate is lowered, that is, when the period of time from the start of switching the mode to the completion of switching the mode is prolonged, it is possible to avoid a sudden temperature change of the conditioned air blown out at the time of switching the mode. Further, in the case where the mode switching means is a door, the door closing rate may be lowered compared with the door opening rate. Due to the foregoing, an intensity of the sound generated at the time of closing the door can be reduced to a level that the passenger cannot detect.

The present invention may be more fully understood from the description of preferred embodiments of the invention set forth below, together with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is an arrangement view showing a model of the battery cooling device 1 and the rear seat side air conditioner 2 for vehicle use;

FIG. 2 is a flow chart showing a process of switching ON/OFF of the battery cooling blower 15;

FIG. 3 is a flow chart showing a process of switching a blower level according to battery temperature T_b;

FIG. 4 is a flow chart showing a process of switching the mode in the first embodiment;

FIG. 5 is a flow chart showing a process of switching the mode in the second embodiment;

FIG. 6 is a view showing modes with respect to battery temperature T_b and air temperature T_am outside the vehicle passenger compartment;

FIG. 7 is a view showing modes with respect to another battery temperature T_b and air temperature T_am outside the vehicle passenger compartment;

FIG. 8 is a view showing modes with respect to battery temperature T_b and air temperature T_b outside the vehicle passenger compartment in the third embodiment;

FIG. 9 is a view showing modes with respect to battery temperature T_b and air temperature T_am outside the vehicle passenger compartment in the fourth embodiment;

FIG. 10 is a view showing a model of the overall arrangement of an air conditioner for vehicle use;

FIG. 11 is a block diagram showing an arrangement of ECU 119;

FIG. 12 is a diagram showing a degree of opening of the correction of the air mixing door 12 with respect to a change in the battery blower level;

FIG. 13 is a diagram showing a correction of the air conditioning blower level with respect to the battery blower level;

FIG. 14 is a flow chart showing the battery blower level calculation processing;

FIG. 15 is a flow chart showing the first half of the processing of switching ON/OFF of the battery blower;

FIG. 16 is a flow chart showing the second half of the processing of switching ON/OFF of the battery blower;

FIG. 17 is a flow chart showing the processing of controlling a battery blower level changing rate;

FIG. 18 is a flow chart showing the processing of the mode switching control;

FIG. 19 is a flow chart showing the air-conditioning blower level calculation correcting control processing; and

FIG. 20 is a flow chart showing the air-mixing door opening degree calculation correcting control processing.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Next, referring to an embodiment, the present invention will be explained in more detail.

First of all, the first embodiment will be explained below.

(1) Outline of Arrangement of Battery Cooling Device and Air Conditioner for Vehicle Use

The battery cooling device 1 for vehicle use of this embodiment is applied to a hybrid powered automobile provided with an internal combustion engine and electric motor which are used for driving the automobile. This hybrid powered automobile includes a front seat side air conditioner (not shown) and a rear side air conditioner 2. Referring to FIG. 1, explanations will be made into an outline of the battery cooling device 1 and the rear seat side air conditioner 2 for vehicle use of this embodiment. FIG. 1 is an arrangement view showing a model of the battery cooling device 1 and the rear seat side air conditioner 2 for vehicle use. In this connection, the front seat side air conditioner for vehicle use is arranged in a front seat side space of the vehicle and mainly conducts air-conditioning on the front seat side in the vehicle passenger compartment.

(1.1) Air Conditioner 2 on Rear Seat Side of Vehicle

The air conditioner 2 on the rear side of a vehicle is arranged in a rear seat side space of the vehicle and mainly conducts air-conditioning on the rear seat side in the vehicle passenger compartment. As shown in FIG. 1, this air conditioner 2 on the rear side of the vehicle includes an air-conditioning case 21, air-conditioning blower 22, evaporator 23, heater core 24, air mixing door 25 and electronic control unit 26 used for the air conditioner.

The air-conditioning case 21 includes: an air inlet 27 for taking air from the rear side in the vehicle passenger compartment; and a conditioned air blowout opening 28 for blowing out the conditioned air to the rear side in the vehicle passenger compartment. Further, the air-conditioning case 21 includes a partitioning plate, which is arranged in the intermediate portion of the passage, for dividing the passage (the left passage in FIG. 1), in which the evaporator 23 is arranged, and the passage (the right passage in FIG. 1) in which the heater core 24 is arranged. These two passages are joined to each other on the downstream side in the air-conditioning case 21.

The blower 22 used for the air conditioner is arranged on the upstream side of the air flow in the air-conditioning case 21. The blower 22 used for the air conditioner sucks air from the air inlet 27 and sends it to the conditioned air blowout opening 28 side. The evaporator (the cooling means) 23 is arranged on one side passage (the left passage in FIG. 1) which is arranged on the downstream side of the air flow of the blower 22 for the air conditioner and branched by the partitioning plate. Therefore, the evaporator (the cooling means) 23 cools air passing through the evaporator. The evaporator 23 composes a heat pump cycle. This heat pump cycle includes a condenser for exchanging heat with the outside air. The heater core 24 is arranged on the downstream side of the air flow of the blower 22 for the air conditioner in the other side passage (the right passage in FIG. 1) partitioned by the partitioning plate. This heater core 24 heats the air passing through the heater core while the cooling water of an internal combustion engine is being used as a heat source.

The air mixing door 25 is arranged on the upstream side of the air flow of the partitioning plate in the air conditioning case 21. The air mixing door 25 adjusts the opening areas of one side passage, in which the evaporator 23 is arranged, and the other side passage in which the heater core 24 is arranged. That is, the air mixing door 25 adjusts the temperature of the conditioned air blowing out from the conditioned air blowout opening 28 of the air-conditioning case 21.

The electronic control unit 26 used for the air conditioner, which will be referred to as ECU for A/C hereinafter, switches ON/OFF of the rear seat side air conditioner 2. Specifically, the electronic control unit 26 switches the drive of the refrigerating cycle including the evaporator 23. Further, ECU 26 for A/C adjusts the temperature of the conditioned air blowing out into the vehicle passenger compartment by controlling the position of the air mixing door 25.

(1.2) Battery Cooling Device 1 for Vehicle Use

The battery cooling device 1 for vehicle use is mounted on the trunk side in the rear seat side space and cools the battery 3 for vehicle use which supplies electric power to an electric motor used for driving. This battery cooling device 1 for vehicle is different from the front seat side air conditioner and the rear seat side air conditioner 2 for vehicle use described before. In this case, the battery 3 for vehicle use is a secondary battery capable of being electrically charged and discharged. This battery 3 for vehicle use stores electric power generated by a generator driven by an internal combustion engine and supplies electric power to an electric motor used for driving.

This battery cooling device 1 for vehicle use includes a battery casing 11, duct 12 inside the vehicle passenger compartment, duct 13 on the trunk side, duct 14 on the evaporator side, blower 15 for cooling the battery, first switching door 16 for switching the suction, second switching door 17 for switching the suction, battery temperature sensor 18 and electronic control unit 19 for cooling the battery which will be referred to as a battery cooling ECU, hereinafter.

The battery casing 11 accommodates the battery 3 for vehicle use and composes a passage of air supplied to the battery 3 for vehicle use. The downstream side of the air flow of this battery casing 11 is communicated with the outside of the vehicle passenger compartment.

The duct 12 inside the vehicle passenger compartment communicates the upstream side of the battery casing 11 with the most upstream side of the air conditioning case 21. That is, the air inside the vehicle passenger compartment is introduced from the air inlet 27, which is formed on the air-conditioning case 21, to the battery 3 side for vehicle use, that is, to the battery casing 11 side. The trunk side duct 13 communicates the upstream side of the air flow of the battery casing 11 with a trunk (not shown). That is, the air in the trunk, which will be referred to as trunk air hereinafter, is introduced to the battery 3 side for vehicle use, that is, to the battery casing 11 side. The evaporator side duct 14 communicates the upstream side of the air flow of the battery casing 11 with the downstream side of the evaporator 23 in one side passage in which the evaporator 23 is arranged in the air-conditioning case 21. That is, the air cooled by the evaporator 23, which will be referred to as cooling air hereinafter, is introduced to the battery 3 side for vehicle use, that is, to the battery casing 11 side.

The battery cooling blower 15 is arranged in a joint portion in which the battery casing 11 and the respective ducts 12 to 14 are joined to each other. This battery cooling blower 15 sucks the air from the vehicle passenger compartment through the air inlet 27 into the battery casing 11 side via the duct 12 inside the vehicle passenger compartment. The battery cooling blower 15 sucks the trunk air from the trunk into the battery casing 11 side via the duct 13 on the trunk side. The battery cooling blower 15 sucks the cooling air to the battery casing 11 side via the duct 14 on the evaporator side. The battery cooling blower 15 blows out the air, which is sucked via the respective ducts 12 to 14, to the battery 3 for vehicle use.

The first door 16 for switching the suction is arranged to be capable of oscillating between the battery casing 11 side of the duct 12 inside the vehicle passenger compartment and the battery casing 11 side of the trunk side duct 13. Therefore, one of the opening on the battery casing 11 side of the duct 12 inside the vehicle passenger compartment and the opening on the battery casing 11 side of the trunk side duct 13 can be closed by the first door 16 for switching the suction.

The second door 17 for switching the suction is arranged to be capable of oscillating between the battery casing 11 side of the duct 12 inside the vehicle passenger compartment and the battery casing 11 side of the duct 14 on the evaporator side. Therefore, one of the opening on the battery casing 11 side of the duct 12 inside the vehicle passenger compartment and the opening on the battery casing 11 side of the duct 14 on the evaporator side duct can be closed by the second door 17 for switching the suction.

That is, according to the positions of the first door 16 for switching the suction and the second door 17 for switching the suction, the air sucked by the battery cooling blower 15, which will be referred to as suction air hereinafter, is selected to be one of the air inside the vehicle passenger compartment, the trunk air and the cooling air. The first door 16 for switching the suction and the second door 17 for switching the suction can switch the suction air among the inside air mode, in which the suction air is the air inside the vehicle passenger compartment, the trunk air mode (the outside air mode), in which the suction air is the trunk air, and the cooling air mode in which the suction air is the cooling air.

The battery temperature sensor 18 detects temperature T_b of the battery 3 for vehicle use, which will be referred to as a battery temperature hereinafter.

Into the battery cooling ECU 19, battery temperature T_b is inputted from the battery temperature sensor 18. Into the battery cooling ECU 19, air temperature T_am outside the vehicle passenger compartment, which is detected by the temperature sensor 4 outside the vehicle passenger compartment, is inputted. Further, into the battery cooling ECU 19, ON/OFF signal of the rear seat side air conditioner 2 is inputted from ECU 26 for A/C use. According to the inputted battery temperature T_b and air temperature T_am outside the vehicle passenger compartment, battery cooling ECU 19 controls ON/OFF of the battery cooling blower 15 and the air volume level of the battery cooling blower 15, which will be referred to as a blower level hereinafter, so that battery temperature T_b can be a temperature not higher than a predetermined temperature (for example, 40° C.). Further, battery cooling ECU 19 controls positions of the first door 16 for switching the suction and the second door 17 for switching the suction. That is, according to various inputted information, battery cooling ECU 19 (the mode switching means) conducts processing of switching a mode among the inside air mode, the trunk air mode and the cooling air mode, that is, battery cooling ECU 19 conducts the mode switching processing.

(2) Processing of Battery Cooling ECU 19

Next, processing of battery cooling ECU 19 will be explained below. As described above, processing of battery cooling ECU 19 includes: ON/OFF switching processing of the battery cooling blower 15; switching processing of the. blower level of the battery cooling blower 15; and mode switching processing.

(2.1) ON/OFF Switching Processing of the Battery Cooling Blower 15

Referring to the flow chart shown in FIG. 2, explanations will be made into ON/OFF switching processing of the battery cooling blower 15. FIG. 2 is a flow chart showing ON/OFF switching processing of the battery cooling blower 15.

As shown in FIG. 2, it is judged whether or not battery temperature T_b, which is inputted from the battery temperature sensor 18, is not. more than the first battery temperature threshold value T_b—th1 (for example 32° C.) (step S1). In the case where battery temperature T_b is not more than the first battery temperature threshold value T_b—th1 (step S1: Yes), it is successively judged whether or not the battery cooling blower 15 is being driven (step S2). In the case where the battery cooling blower 15 is being driven (ON) (step S2: Yes), the battery cooling blower 15 is stopped (OFF) (step S3), and the processing is ended. On the other hand, in the case where battery temperature T_b is not more than the first battery temperature threshold value T_b—th1 and the battery cooling blower 15 is stopped (OFF) (step S2: No), the processing is ended as it is.

In the case where battery temperature T_b is higher than the first battery temperature threshold value T_b—th1 (step S1: No), it is successively judged whether or not the battery cooling blower 15 is being driven (step S4). In the case where the battery cooling blower 15 is being driven (ON) (step S4: Yes), the processing is ended as it is. On the other hand, in the case where battery temperature T_b is higher than the first battery temperature threshold value T_b—th1 and the battery cooling blower 15 is stopped (OFF) (step S4: No), the battery cooling blower 15 is driven (ON) (step S5), and the processing is ended as it is.

That is, in the case where battery temperature T_b is not more than the first battery temperature threshold value T_b—th1, the battery cooling blower 15 is stopped. In the case where battery temperature T_b is higher than the first battery temperature threshold value T_b—th1, the battery cooling blower 15 is driven.

(2, 2) Switching of Blower Level according to Battery Temperature T_b

Next, referring to the flow chart in FIG. 3, switching of blower level will be explained below. FIG. 3 is a flow chart showing a process of switching a blower level according to battery temperature T_b.

As shown in FIG. 3, first of all, it is judged whether or not the battery cooling blower 15 is being driven (ON) (step S11). In the case where the battery cooling blower 15 is stopped (OFF) (step S11: No), the processing is ended as it is. On the other hand, in the case where the battery cooling blower 15 is being driven (ON) (step S11: Yes), it is successively judged whether or not battery temperature T_b is in a predetermined temperature range (T_b—min (n)≦T_b≦T_b—max (n)) at the present blower level (step S12). In this case, the predetermined temperature range at the blower level is a temperature range which is set for each blower level. For example, the temperature range at the minimum blower level is set in the temperature range from 32° C. to 35° C. In this case, n in the above conditional expression is a blower level value, T_bmin (n) is the minimum temperature at the level n, and T_bmax (n) is the maximum temperature at the level n.

In the case where battery temperature T_b is in the predetermined temperature range at the present blower level (step S12: Yes), the processing is ended while the present blower level is being maintained. On the other hand, in the case where battery temperature T_b is not in the predetermined temperature range at the present blower level (step S12: No), it is further judged whether or not battery temperature T_b is lower than the minimum temperature T_b—min (n) in the temperature range at the present blower level (step S13). In the case where battery temperature T_b is lower than the minimum temperature T_b—min (n) concerned (step S13: Yes), the blower level is lowered by one level, and the processing is ended (step S14). As the battery 3 for vehicle use is sufficiently cooled, processing is conducted so that the blower level can be lowered.

On the other hand, in the case where battery temperature T_b is not lower than the minimum temperature T_b—min (n) in the temperature range at the present blower level (step S13: No), that is, in the case where battery temperature T_b is higher than the maximum temperature T_b—max (n) in the temperature range at the present blower level, the blower level is raised by one level, and the processing is ended (step S15). As the battery 3 for vehicle use is not sufficiently cooled at the present blower level, the processing is conducted so that the blower level can be raised.

(2.3) Processing of Switching the Mode

Next, referring to FIG. 4, the mode switching processing will be explained below. FIG. 4 is a flow chart showing a process of switching the mode in the first embodiment.

As shown in FIG. 4, first of all, it is judged whether or not the outside air temperature T_am is not more than outside air temperature threshold value T_am—th (for example, 30° C.) (step S21). In the case where outside air temperature T_am is not more than outside air temperature threshold value T_am—th (step S21: Yes), the mode is switched to the trunk air mode (step S22). Specifically, the trunk air is introduced into the battery casing 11 and blown out to the battery 3 for vehicle use.

When the mode is switched to the trunk air mode, it is successively judged whether or not the blower level of the battery cooling blower 15 is the maximum level (step S23). In the case where the blower level of the battery cooling blower 15 is not the maximum level (step S23: No), the judgment is repeated until the blower level becomes the maximum level. That is, until the blower level becomes the maximum level, the trunk mode can be maintained.

On the other hand, in the case where the blower level is the maximum level (step S23: Yes), it is further judged whether or not the blower level raising processing is going to be conducted in step S15 in FIG. 3 (step S24). In the case where the blower level raising processing is not going to be conducted at the maximum blower level (step S24: No), the program is returned to step S23 and the processing is repeated.

On the other hand, in the case where the blower level raising processing is going to. be conducted at the maximum blower level (step S24: Yes), the mode is switched to the inside air mode (step S25).

In this connection, in the case where outside air temperature T_am is higher than outside air temperature threshold value T_am—th (step S21: No), the mode is switched to the inside air mode (step S25).

When the mode is switched to the inside air mode, it is judged whether or not the blower level is the minimum level (step S26). In the case where the blower level is the minimum level (step 26: Yes), it is further judged whether or not the blower level lowering processing is going to be conducted in step S14 in FIG. 3 (step S27). In the case where the blower level lowering processing is going to be conducted at the minimum blower level (step 27: Yes), the mode is switched to the trunk air mode (step S32).

On the other hand, in the case where the blower level is not the minimum level (step S26: No) or in the case where the blower level is the minimum level and the blower level lowering processing is not going to be conducted (step S27: No), it is judged whether or not the blower level is the maximum level (step S28). In the case where the blower level is not the maximum level (step S28: No), the program is returned to step S26 and the processing is repeated.

On the other hand, in the case where the blower level is the maximum level (step S28: Yes), it is further judged whether or not the blower level raising processing is going to be conducted in step S15 in FIG. 3 (step S29). In the case where the blower level raising processing is not going to be conducted at the maximum blower level (step S29: No), the program is returned to step S26 and the processing is repeated.

On the other hand, in the case where the blower level raising processing is going to be conducted at the maximum blower level (step S29: Yes), it is successively judged whether or not the rear seat side air conditioner 2 is being driven (ON) (step S30).

In the case where the battery cooling device 1 is being driven (step S30: Yes), the mode is switched to the cooling air mode (step S31). At this time, the blower level of the battery cooling blower 15 is fixed. Successively, it is judged whether or not battery temperature T_b is not more than the second battery temperature threshold value T_b—th2 (step S32). In the case where battery temperature T_b is higher than the second battery temperature threshold value T_b—th2 (step S32: No), the processing is repeated until battery temperature T_b is decreased to a value not higher than the second battery temperature threshold value T_b—th2. On the other hand, in the case where battery temperature T_b is not more than the second battery temperature threshold value T_b—th2 (step S32: Yes), the mode is switched to the inside air mode (step S25), and the processing is repeated.

In the case where A/C is not being driven as a result of judging whether or not the battery cooling device 1 is being driven (step S31: No), while the inside air mode is being maintained, processing is conducted so that an output of the battery 3 for vehicle use can be reduced (step S33). Then, the program is returned to step S26 and the processing is repeated.

As explained above, in the case where outside air temperature T_am is not more than outside air temperature threshold value T_am—th, switching is conducted in the order of the trunk air mode, the inside air mode and the cooling air mode. On the other hand, in the case where outside air temperature T_am is higher than outside air temperature threshold value T_am—th, switching is conducted in the order of the inside air mode and the cooling air mode.

Next, the second embodiment will be explained below. Only the mode switching processing of the second embodiment is different from that of the first embodiment. Therefore, only the mode switching processing will be explained as follows. The mode switching processing conducted in the second embodiment will be explained referring to FIG. 5. FIG. 5 is a flow. chart showing a process of switching the mode in the second embodiment.

As shown in FIG. 5, first of all, it is judged whether or not outside air temperature T_am is not more than the first outside air temperature threshold value T_am—th1 (for example, 25° C.) (step S41). In the case where outside air temperature T_am is not more than the first outside air temperature threshold value T_am—th1 (step S41: Yes), the mode is switched to the trunk air mode (step S42), and the processing is ended.

On the other hand, in the case where outside air temperature T_am is higher than the first outside air temperature threshold value T_am—th1 (step S41: No), it is further judged whether or not outside air temperature T_am is not more than the second outside air temperature threshold value T_am—th2 (for example, 30° C.) (step S43). In the case where outside air temperature T_am is not more than the second outside air temperature threshold value T_am—th2 (step S43: Yes), it is further judged whether or not battery temperature T_b is not more than the first battery temperature threshold value T_b—th3 (step S44). In the case where battery temperature T_b is not more than the first battery temperature threshold value T_b—th3 (for example, 43° C.) (step S44: Yes), the mode is switched to the trunk air mode (step S42), and the processing is ended.

On the other hand, in the case where outside air temperature T_am is higher than the second outside air temperature threshold value T_am—th2 (step S43: No) or in the case where outside air temperature T_am is not more than the second outside air temperature threshold value T_am—th2 and battery temperature T_b is higher than the first battery temperature threshold value T_b—th3 (step 44: No), it is further judged whether or not battery temperature T_b is not more than the second battery temperature threshold value T_b—th4 (for example, 45° C.) (step S45). In the case where battery temperature T_b is not more than the second battery temperature threshold value T_b—th4 (step S45: Yes), the mode is changed to the inside air mode (step S46), and the processing is ended.

On the other hand, in the case where battery temperature T_b is higher than the second battery temperature threshold value T_b—th4 (step S45: No), it is further judged whether or not the rear seat side air conditioner 2 is being driven (ON) (step S47). In the case where the rear seat side air conditioner 2 is not being driven (step S47: No), the mode is switched to the inside air mode (step S46), and the processing is ended.

On the other hand, in the case where battery temperature T_b is higher than the second battery temperature threshold value T_b—th4 and the rear seat side air conditioner 2 is being driven (step S47: Yes), the mode is switched to the cooling air mode (step S48).

Referring to FIG. 6, a relation of each mode with respect to battery temperature T_b and outside air temperature T_am in the case where the mode is switched as described above will be explained below. FIG. 6 is a view showing modes with respect to battery temperature T_b and air temperature T_am outside the vehicle passenger compartment. As shown in FIG. 6, in the case where outside air temperature T_am is not more than the first outside air temperature threshold value T_am—th1, the mode is set in the trunk air mode.

In the case where outside air temperature T_am is higher than the first outside air temperature threshold value T_am—th1 and not more than the second outside air temperature threshold value T_am—th2, the mode is different according to battery temperature T_b. Specifically, in the case where battery temperature T_b is not more than the first battery temperature threshold value T_b—th3, the mode is the trunk air mode. In the case where battery temperature T_b is higher than the first battery temperature threshold value T_b—th3 and not more than the second battery temperature threshold value T_b—th4, the mode is the inside air mode. Further, in the case where battery temperature T_b is higher than the second battery temperature threshold value T_b—th4, the mode is the cooling air mode in principle. However, if the rear seat side air conditioner 2 is not being driven, in the case where battery temperature T_b is higher than the second battery temperature threshold value T_b—th4, the mode is the inside air mode.

In the case where outside air temperature. T_am is higher than the second outside air temperature threshold value T_am—th2, the mode is different according to battery temperature T_b. Specifically, in the case where battery temperature T_b is not more than the second battery temperature threshold value T_b—th4, the mode is the inside air mode. In the case where battery temperature T_b is higher than the second battery temperature threshold value T_b—th4, the mode is the cooling air mode in principle. However, if the rear seat side air conditioner 2 is not being driven, in the case where battery temperature T_b is higher than the second battery temperature threshold value T_b—th4, the mode is the inside air mode.

In this case, a relation of each mode with respect to battery temperature T_b and outside air temperature T_am may be set as shown in FIG. 7., FIG. 7 is a view showing each mode with respect to battery temperature T_b and air temperature T_am outside the vehicle passenger compartment in the same manner as that of FIG. 6.

As shown in FIG. 7, in the case where outside air temperature T_am is higher than the first outside air temperature threshold value T_am—th1 and not more than the second outside air temperature threshold value T_am—th2, the first battery threshold value T_b—th3 is made to be different according to air temperature T_am outside the vehicle passenger compartment. Specifically, in the case where outside air temperature T_am is higher than the first outside air temperature threshold value T_am—thl and not more than the second outside air temperature threshold value T_am—th2, when outside air temperature T_am is high, the first battery threshold value T_b—th3 is made to be low, and when outside air temperature T_am is lower, the first battery threshold value T_b—th3 is made to be higher.

In this connection, in the above embodiment, the evaporator side duct 14 is communicated with the downstream side of the evaporator 23, which is located in one side passage in which the evaporator 23 is arranged, in the air conditioning case 21 of the rear side air conditioner 2. However, the present invention is not limited to the above specific embodiment. For example, the evaporator side duct 14 may be communicated with the downstream side of the evaporator of the air conditioning case of the front seat side air conditioner (not shown). That is, when the battery cooling device 1 is in the cooling air mode, the cooling air may be introduced from the rear seat side air conditioner to the battery casing 11 side.

Next, referring to FIG. 8, the third embodiment of the present invention will be described as follows. The third embodiment is greatly different from the above second embodiment in the viewpoint that no trunk air mode exists in the third embodiment. Accordingly, the battery cooling device 1 of this embodiment (not shown) does not include the trunk side duct 13 and the first door 16 for switching the suction which are illustrated in FIG. 1. Other structural points such as blower level switching processing of the third embodiment are the same as those of the first and the second embodiment.

The mode switching control of this embodiment is conducted as follows. As shown in FIG. 8, in the case where outside air temperature T_am is higher than predetermined temperature T_am—th (T_am—th =0° C., in this embodiment), the suction mode is selected between the inside air mode and the cooling air mode according to the above battery temperature T_b. In the case where outside air temperature T_am is not more than the predetermined temperature T_am—th, the inside air mode is selected.

Specifically, in the case where outside air temperature T_am is higher than the above predetermined temperature T_am—th, when battery temperature T_b is lower than reference temperature T_b—th, the inside air mode is selected. When battery temperature T_b is not less than reference temperature T_b—th, the cooling air mode is selected. In this connection, in this embodiment, it is set that when outside air temperature T_am is raised, reference temperature T_b—th is lowered.

Due to the foregoing, when the outside air temperature is so low that the evaporator cannot exhibit the cooling capacity, the inside air mode can be selected.

When outside temperature T_am is raised, the air temperature in the vehicle passenger compartment is also raised in many cases. In this case, it is desirable to transfer the mode to the cooling air mode earlier than the usual case. In this embodiment, it is set that when outside air temperature T_am is raised, reference temperature T_b—th, at which the cooling air mode is used, is set at a lower value. Therefore, when outside air temperature T_am is raised high, it is possible to transfer to the cooling air mode earlier than the usual case.

In this connection, in the cooling air mode of the first and the second embodiment, only the cooling ail, which has passed through the evaporator of the air conditioner for vehicle use, is used. However, in the cooling air mode of this embodiment, both the cooling air, which has passed through the evaporator of the air conditioner for vehicle use, and the air inside the vehicle passenger compartment are simultaneously used. Due to the foregoing, it becomes possible to blow out a large volume of cooling air flow to the battery without missing a feeling of air-conditioning in the vehicle passenger compartment. This effect is not limited to the present embodiment, that is, this effect can be provided in the first and the second embodiment described before. Naturally, in the same manner as that of the first and the second embodiment, only the cooling air may be used for the cooling air mode of this embodiment.

Next, referring to FIG. 9, the fourth embodiment of the present invention will be described below. When the fourth embodiment is compared with the above third embodiment, the different point is described as follows. In the fourth embodiment, the cooling air mode in the third embodiment is divided into one region, in which only the cooling air is used, and the other region in which both the cooling air and the inside air are used. Other points of the fourth embodiment are the same as those of the third embodiment.

As shown in FIG. 9, the mode switching control is conducted in this embodiment as follows. In the case where temperature T_am of the air outside the vehicle passenger compartment is higher than predetermined temperature T_am—th (T_am—th=0° C. in this embodiment), according to the value of battery temperature T_b, the suction mode is selected among the inside air mode, the cooling air mode and the mode in which both the inside air and the cooling air are used. In the case where temperature T_am of the air outside the vehicle passenger compartment is not more than predetermined temperature T_am—th, the inside air mode is selected.

Specifically, the mode is selected as follows. In the case where temperature T_am of the air outside the vehicle passenger compartment is higher than. predetermined temperature T_am—th, when battery temperature T_b is lower than reference temperature T_b—th5, the inside air mode is selected. In the case where temperature T_am of the air outside the vehicle passenger compartment is higher than predetermined temperature T_am—th, when battery temperature T_b is not less than reference temperature T_b—th5 and lower than reference temperature T_b—th6, the cooling air mode is selected. In the case where temperature T_am of the air outside the vehicle passenger compartment is higher than predetermined temperature T_am—th, when battery temperature T_b is not less than reference temperature T_b—th6, the mode, in which both the inside air and the cooling air are used, is selected.

In the same manner as that of the third embodiment, it is set that when temperature T_am of the air outside the vehicle passenger compartment is raised higher, reference temperatures T_b—th5 and T_b—th6 are decreased.

In this embodiment, in the case where temperature T_am of the air outside the vehicle passenger compartment is higher than predetermined temperature T_am—th and battery temperature T_b is not less than reference temperature T_b—th6, controlling may be conducted so that a volume of air blown out by the blower can be increased.

In this connection, in the third embodiment and this embodiment, in the same manner as that of the first and the second embodiment described above, in the vehicle having both the front seat side air conditioner and the rear seat side air conditioner, the battery cooling device uses the cooling air cooled by the evaporator which is a cooling means incorporated into the rear seat side air conditioner. However, the present invention is not limited to the above specific embodiment. The battery cooling device may use the cooling air which has passed through the evaporator incorporated into the front seat side air conditioner. Naturally, the present invention may be applied to a vehicle having only the front seat side air conditioner.

Next, referring to FIGS. 10 to 20, the air conditioner for vehicle use of the fifth embodiment of the present invention will be described as follows.

(3) Arrangement of Air Conditioner for Vehicle Use

First of all, referring to FIG. 10, the arrangement of the air conditioner for vehicle use will be explained below. FIG. 10 is a view showing a model of the overall arrangement of the air conditioner for vehicle use. In this connection, the void arrow in FIG. 10 shows a flow of air. This air conditioner for vehicle use includes an air conditioning unit 102, a battery cooling unit 101 and ECU (control means) 119.

(3.1) Air Conditioning Unit 102

The air conditioning unit 102 is arranged on the rear seat side and conducts air-conditioning mainly on the rear seat side. As shown in FIG. 10, this air conditioning unit 102 includes an air-conditioning case 121, evaporator (cooling air generating means) 123, heater core (heating air generating means) 122, air mixing door (conditioned air generating means) 125, air conditioning blower 122, blowout air temperature sensor (conditioned air blowout temperature detecting means) 131, air-conditioning operation panel 132, air-conditioning blower drive circuit 133 and air mixing door servo motor 134.

The air-conditioning case 121 includes: an air inlet 127 for taking air from the rear side in the vehicle passenger compartment; and a conditioned air blowout opening 128 for blowing out the conditioned air to the rear side in the vehicle passenger compartment. Further, the air-conditioning case 121 includes a partitioning plate 130, which is arranged in the intermediate portion of the passage, for dividing the passage, in which the evaporator 123 is arranged, and the passage in which the heater core 124 is arranged. These two passages are joined to each other on the downstream side in the air-conditioning case 121.

The evaporator 123 is arranged in the air-conditioning case 121. To be specific, the evaporator 123 is arranged between the air inlet 127 and the conditioned air blowout opening 128. To be more specific, the evaporator 123 is arranged in one side passage (the left passage with respect to the partition plate 130 in FIG. 10) with respect to the partition plate 130. The evaporator 123 composes a heat pump cycle. This heat pump cycle includes a condenser for exchanging heat with the outside air. This evaporator 123 cools the upstream side air, which is passing in the evaporator, so that the cooling air can be generated on the downstream side.

The heater core 124 is arranged in the air-conditioning case 121. To be specific, the heater core 124 is arranged between the air inlet 127 and the conditioned air blowout opening 128. To be more specific, the heater core 124 is arranged in the other side passage (the right passage with respect to the partition plate 130 in FIG. 10) with respect to the partition plate 130. This heater core 124 heats the upstream side air, which is passing through the heater core, so that the heating air can be generated on the downstream side.

The air mixing door 125 is arranged on the upstream side of the air flow of the partition plate 130 in the air conditioning case 121 and adjusts the opening areas of one side passage, in which the evaporator 123 is arranged, and the other side passage in which the heater core 124 is arranged. Due to the foregoing, the air mixing door 125 generates a flow of conditioned air in such a manner that a flow of cooling air generated by the evaporator 123 and a flow of heating air generated by the heater core 124 are joined to each other on the downstream side of the partitioning plate 130.

Therefore, when the degree of opening of this air mixing door is adjusted, it is possible to freely set a ratio of the hot air to the cold air. For example, in the case where the air mixing door 125 opens one side passage on the evaporator 123 side and closes the other side passage on the heater core 124 side, the conditioned air can be generated only from the cooling air, and the temperature of the conditioned air is decreased to the lowest value. On the other hand, in the case where the air mixing door 125 closes one side passage on the evaporator 123 side and opens the other side passage on the heater core 124 side, the conditioned air can be generated from only the heating air, and the temperature of the conditioned air is increased to the highest value.

The air-conditioning blower 122 is arranged on the upstream side of the air flow in the air conditioning case 121 and blows out the air, which has been sucked from the vehicle passenger compartment via the air inlet 127, to a passenger located in the air-conditioning blowout opening 128 side. This air-conditioning blower 122 generates a flow of conditioned air, which is generated on the downstream side of the air-conditioning blower 122, so that the flow of conditioned air can be blown out to the passenger.

The blowout air temperature sensor 131 detects the conditioned air blowout temperature T_a which is the temperature of the conditioned air generated and blown out from the air-conditioning blower 122.

On the air conditioner operation panel 132, various operation switches such as a vehicle passenger compartment temperature setting switch and an air-conditioning switch are arranged. The vehicle passenger compartment temperature setting switch is used for setting the temperature in the air-conditioning zone in the vehicle passenger compartment at a desired temperature (a setting temperature in the vehicle passenger compartment) T_set. The air-conditioning switch is used for driving the evaporator 123 and the heater core 124.

The air-conditioning blower drive circuit 133 is used for driving a motor (not shown) to rotate the air-conditioning blower 122. The actuator of the air mixing door servo motor 134 is used for driving the air mixing door 125.

(3.2) Battery Cooling Unit 101

The battery cooling unit 101 for vehicle use is mounted on the trunk side in the rear seat side space and cools the battery 103 for vehicle use which supplies electric power to an electric motor used for driving a vehicle. In this case, the battery 103 for vehicle use is a secondary battery capable of being electrically charged and discharged. This battery 103 for vehicle use stores electric power generated by a generator driven by an internal combustion engine and supplies electric power to the electric motor used for driving the vehicle. As shown in FIG. 10, this battery cooling unit 101 includes a battery casing 111, inside vehicle passenger compartment duct 112, evaporator side duct 114, battery cooling blower 115, battery temperature sensor 118, battery blower drive circuit 135 and mode switching door 136.

The battery casing 111 accommodates the battery 103 for vehicle use and composes a passage of air supplied to the battery 103 for vehicle use. The downstream side of the air flow of this battery casing 111 is communicated with the outside of the vehicle passenger compartment.

The duct 112 inside the vehicle passenger compartment communicates the upstream side of the air flow of the battery casing 111 with the most upstream side of the air conditioning case 121. That is, the air inside the vehicle passenger compartment is introduced from the air inlet 127, which is formed on the air-conditioning case 121, to the battery 103 side for vehicle use, that is, to the battery casing 111 side.

The evaporator side duct 114. communicates the upstream side of the air flow of the battery casing 111 with the downstream side of the evaporator 123 in one side passage in which the evaporator 123 is arranged in the air-conditioning case 121. That is, the air cooled by the evaporator 123 is introduced to the battery 103 side for vehicle use, that is, to the battery casing 111 side.

The battery cooling blower 115 is arranged in a joint portion in which the battery casing 111, the vehicle passenger compartment inside duct 112 and the evaporator side duct 114 are joined to each other. This battery cooling blower 115 sucks the air in the vehicle passenger compartment from the air inlet 127 to the battery casing 111 side via the duct 112 inside the vehicle passenger compartment. The battery cooling blower 115 sucks the cooling air to the battery casing 111 side via the evaporator side duct 114. The battery cooling blower 115 sucks the cooling air via the duct 112 inside the vehicle passenger compartment and the evaporator side duct 114 and blows out the thus sucked air to the battery 103 for vehicle use so as to cool the battery 103.

The battery temperature sensor 118 detects temperature T_b of the battery 103 for vehicle use, which will be referred to as a battery temperature T_b hereinafter. The battery blower drive circuit 135 is used for driving a motor (not shown) attached to the battery cooling blower 115.

The mode switching door 136 is arranged to be capable of oscillating between the battery casing 111 side of the duct 112 inside the vehicle passenger compartment and the battery casing 111 side of the evaporator side duct 114. The mode switching door 136 is controlled so that one of the opening on the battery casing 111 side of the duct 112 inside the vehicle passenger compartment and the opening on the battery casing 111 side of the evaporator side duct 114 can be closed by the mode switching servo motor 137. In other words, the mode switching servo motor 137 can change a position of the mode switching door 136 so that switching can be conducted between the inside air mode, in which the air sucked into the battery cooling blower 115 (This air is referred to as suction air hereinafter.) is used as the air inside the vehicle passenger compartment, and the cooling air mode in which the suction air is used as the cooling air.

(3.3) Outline of Arrangement of ECU 119

Referring to FIG. 10, an outline of the arrangement of ECU 119 will be explained below. ECU 119 is connected to a blowout air temperature sensor 131, a battery temperature sensor 118, a cooling air temperature sensor 161 for detecting cooling air temperature T_e, which is referred to as an after-evaporator temperature hereinafter, after the cooling air has passed through the evaporator 123, and a cooling water temperature sensor 162 for detecting engine cooling water temperature T_w which is referred to as a cooling water temperature hereinafter. Signals outputted from various operation switches on the air conditioner operation panel 132 are inputted into ECU 119.

(4) Detailed Description of Arrangement of ECU 119

Next, referring to FIG. 11, an arrangement of ECU 119 will be explained in detail. FIG. 11 is a block diagram showing the arrangement of ECU 119. ECU 119 controls the electric actuators 133, 134, 135, 137 according to the signals outputted from the blowout air temperature sensor 131, the battery temperature sensor 118, the cooling air temperature sensor 161, the cooling water temperature sensor 162, and various switches on the air conditioner operation panel 132.

As shown in FIG. 11, this ECU 119 includes: an input section 141, battery blower level calculating section 142, battery blower level control section (battery air flow volume level control means) 143, mode switching section 144, inside vehicle passenger compartment target blowout air temperature (TAO) calculating section 145, air mixing door opening degree calculating section (air conditioning air ratio calculating means) 146, air mixing door opening degree correcting section (the hot air to the cold air ratio correcting means) 147, air mixing door opening degree control section 148, air conditioning blower level calculating section 149, air conditioning blower level correcting section (air conditioning air flow volume level correcting means) 150, and air conditioning blower level control section (air conditioning air flow volume level control mean) 151.

Signals, which are outputted from the blowout air temperature sensor 131, the battery temperature sensor 118, the cooling air temperature sensor 161, the cooling water temperature sensor 162 and various switches on the air conditioner operation panel 132, are inputted into the input section 141.

The battery blower level calculating section 142 calculates an air flow volume level of the cooling air blown to the battery, which will be referred to as a battery blower level hereinafter, according to battery temperature T_b inputted into the input section 141. The battery blower level calculating section 142 is inputted with a battery blower QN/OFF signal outputted from the battery blower level control section 143.

According to the battery blower ON/OFF switching processing and the battery blower level changing rate control processing, the battery blower control section 143 controls the battery blower drive circuit 135. By the battery blower ON/OFF switching processing, the battery blower ON/OFF signal is outputted so that ON/OFF of the battery blower drive circuit 135 can be switched according to the battery temperature T_b inputted into the input section 141, also according to the battery blower level calculated by the battery blower level calculating section 142 and according to the mode switching completion signal outputted from the mode switching control section 144 described later. Further, by the battery blower ON/OFF switching processing, the battery blower ON/OFF switching completion signal is outputted when a state of the battery blower is switched to OFF.

By the battery blower level change rate control processing, the battery blower drive circuit 135 is controlled so that the battery blower level change rate can be adjusted according to air-conditioning blowout air temperature T_a inputted into the input section 141 and also according to the battery blower level calculated by the battery blower level calculating section 142.

According to the battery blower ON/OFF switching completion signal which is outputted from the battery blower level control section 143, the mode switching control section 144 controls the mode switching servo motor 137 so that the mode switching door 136 can be opened and closed. After the mode switching door 136 has been opened or closed, the mode switching control section 144 outputs a signal of the completion of mode switching to the battery blower level control section 143. In this connection, this mode switching control section 144 controls the mode switching servo motor 131 so that the opening and closing rate of the mode switching door 136 can be adjusted. Specifically, the mode switching control section 144 controls so that a rate of closing the opening portion of the vehicle passenger compartment inside duct 112 by the mode switching door 136, which will be referred to as a closing rate hereinafter, can be lower than a rate of opening the opening portion of the evaporator side duct 114 by the mode switching door 136, which will be referred to as an opening rate hereinafter, when the mode is switched from the inside air mode, in which the opening portion of the evaporator side duct 114 is closed, to the cooling air mode in which the opening portion of the vehicle passenger compartment inside duct 112 is closed. In the same manner, the mode switching control section 144 controls so that a rate of closing the mode switching door 136, which is a closing rate of closing the opening portion of the evaporator side duct 114, can be lower than an opening rate of opening the mode switching door 136, which is an opening rate of opening the opening portion of the duct 112 inside the vehicle passenger compartment, when the mode is switched from the cooling air mode to the inside air mode.

TAO calculating section 145 calculates TAO according to inside vehicle passenger compartment setting temperature T_set, which is inputted into the input section 141, and temperature T_ir of the inside vehicle air-conditioning zone by Expression 1.
TAO=K_set×T_set−K_ir×T_ir+C   (Expression 1)

TAO: Inside vehicle passenger compartment target blowout air temperature

T_set: Inside vehicle setting temperature

T_ir: Inside vehicle passenger compartment air-conditioning zone temperature

K_set, K_ir: Coefficients

C: Constant

Air mixing door opening degree calculating section 146 calculates the air mixing door opening degree by Expression 2 according to after-evaporator temperature T_e of the air, which has passed through the evaporator 123, inputted into the input section 141 and also according to cooling water temperature T_w and inside vehicle passenger compartment target blowout air temperature TAO calculated by TAO calculating section 145. In this case, in the case where the opening degree of the air mixing door is 0%, the conditioned air contains only the cooling air. Therefore, the temperature becomes the lowest. On the other hand, in the case where the opening degree of the air mixing door is 100%, the conditioned air contains only the heating air. Therefore, the temperature becomes the highest.
SW={(TAO−T_e)/(T_w−T_e)}×100   (Expression 2)

SW (%): Opening degree of air mixing door

TAO: Inside vehicle passenger compartment target blowout air temperature

T_e: After-evaporator temperature

Tw: Cooling water temperature

The air mixing door opening degree correcting section 147 reads in a state of the mode of the mode switching door 136 from the mode switching control section 144, that is, the air mixing door opening degree correcting section 147 reads in whether the mode is the inside air mode or the cooling air mode. The air mixing door opening degree correcting section 141 corrects the opening degree of the air mixing door, which is calculated by the air mixing door opening degree calculating section 146, according to the battery blower level calculated by the battery blower level calculating section 142. Referring to FIG. 12, explanations will be made into the correction conducted by this air mixing door opening degree correcting section 147. FIG. 12 is a diagram showing a degree of opening of correction of the air mixing door 125 with respect to a change in the battery blower level. As shown by the arrows in FIG. 12, for example, in the case where the battery level is increased from n to (n+1) by one level, the air mixing door correcting section 147 conducts a correction so that the air mixing door opening degree can be decreased. That is, in the case where the battery blower level is increased, the opening degree correcting section 147 of the air mixing door increases and corrects a ratio of the cooling air, which generates the conditioned air, so that conditioned air blowout temperature T_a can be maintained constant. On the other hand, in the case where the battery blower level is decreased from (n+1) to n by one level, the air mixing door correcting section 147 conducts a correction so that the air mixing door opening degree can be decreased. That is, in the case where the battery blower level is decreased, the air mixing door opening degree correcting section decreases. and corrects a ratio of the cooling air, which generates the conditioned air, so that conditioned air blowout temperature T_a can be maintained constant.

In this connection, when the battery blower level is changed, a correction of the air mixing door opening degree for correcting so that high conditioned air blowout temperature T_a1 can be maintained is larger than a correction of the air mixing door opening degree for correcting so that low conditioned air blowout temperature T_a2 (T_a1>T_a2) can be maintained. Specifically, compared with a case in which conditioned air blowout temperature T_a is maintained at 10° C., in the case where conditioned air blowout temperature T_a is maintained at 13° C., a correction of the air mixing door, which is accompanied by an increase in the battery blower level by one level, is large.

The air mixing door opening degree control section 148 controls the air mixing door servo motor 134 according to the air mixing door opening degree corrected by the air mixing door opening degree correcting section 147.

The air conditioning blower level calculating section 149 calculates a blower level of the conditioned air blown out from the air-conditioning blower 122, which will be referred to as an air-conditioning blower level hereinafter, according to various signals inputted into the input section 141 and also according to TAO calculated by TAO calculating section.

The air-conditioning blower level correcting section 150 reads in a state of the mode of the switching door 136 from the mode switching control section 144, that is, the air-conditioning blower level correcting section 150 reads in whether the mode is the inside air mode or the cooling air mode. In the case where the state of the mode switching door 136 is the inside air mode, the air-conditioning blower level correcting section 150 does not correct the air-conditioning blower level. On the other hand, in the case where the state of the. mode switching door 136 is the cooling air mode, the air-conditioning blower level correcting section 150 corrects the air-conditioning blower level. The air-conditioning blower level correcting section 150 corrects an air-conditioning blower level, which is calculated by the air-conditioning blower level calculating section 149, according to the battery blower level calculated by the battery blower level calculating section 142. Referring to FIG. 13, this correction of the air-conditioning blower level will be explained below. FIG. 13 is a diagram showing a correction of the air conditioning blower level with respect to the battery blower level. As shown in FIG. 13, the battery blower level is proportional to the correction of the air-conditioning blower level. The air-conditioning blower level correcting section 150 increases a correction of the air-conditioning blower level as the battery blower level is increased, and this correction is added to the air-conditioning blower level calculated by the air-conditioning blower level calculating section 149. In this connection, in the case where the battery blower level is 0, that is, in the case where the battery cooling blower 115 is not being driven, the correction of the air-conditioning blower level is 0. The air-conditioning blower level correcting section 151 controls the air-conditioning blower drive circuit 133 according to the air-conditioning blower level corrected by the air-conditioning blower level correcting section 150.

(5) Processing of ECU 119

Next, referring to FIGS. 14 to 20, the processing of ECU 119 will be explained below. In this case, ECU 119 conducts the battery blower level calculation control processing, the mode switching control processing, the air-conditioning blower level calculation correction control processing and the air-mixing door opening degree calculation correction control processing.

(5.1) Battery Blower Level Calculation Control Processing

The battery blower level calculation control processing includes: battery blower level calculation processing conducted in the battery blower level calculating section 142; battery blower ON/OFF switching processing conducted in the battery blower level control section 143; and battery blower level change rate control processing.

(5.1.1) Battery Blower Level Calculation Processing

Referring to FIG. 14, the battery blower level calculation processing will be explained below. FIG. 14 is a flow chart showing the battery blower level calculation processing. First, battery temperature T_b inputted into the input section 141 is read in (step S101). According to ON/OFF signal of the battery blower outputted from the battery blower level control section 143, it is judged whether or not the battery blower is ON, that is, it is judged whether or not the battery cooling blower 115 is being driven (step S102). In the case where the battery blower is OFF, that is, the battery cooling blower 115 is being stopped (step S102: No), the processing is ended as it is. On the other hand, in the case where the battery blower is being driven (ON), that is, the battery cooling blower 115 is being driven (step S102: Yes), it is judged whether or not battery temperature T_b is in a predetermined temperature range (T_b—min(n)≦T_b≦T_b—max) at the present battery blower level (step S103). In this case, the predetermined temperature range at the battery blower level is defined as a temperature range which is set at each battery blower level. For example, the battery blower level is set in the range from 32° C. to 35° C. which is the minimum level temperature range. In the conditional expression, n is a level value of the battery blower level, T_b—min(n) is the minimum temperature at level n, and T_b—mmax(n) is the maximum temperature at level n. In the case where battery temperature T_b is in the predetermined temperature range at the present battery blower level (step S103: Yes), the processing is ended while the present battery blower level is being maintained. On the other hand, in the case where battery temperature T_b is not in the predetermined temperature range at the present battery blower level (step S103: No), it is further judged whether or not battery temperature T_b is lower than the minimum temperature T_b—min(n) of the temperature range at the present battery blower level (step S104). In the case where battery temperature T_b is lower than the minimum temperature T_b—min(n) (step S104: Yes), the battery blower level is decreased by 1 level, and the processing is ended (step S105). That is, as the battery 103 is sufficiently cooled, processing is conducted so that the battery blower level is decreased. On the other hand, in the case where battery temperature T_b is higher than T_b—max(n). (step S104: No), the battery blower level is increased by 1 level, and the processing is ended. That is, as the battery 103 not sufficiently cooled, the processing is conducted so that the battery blower level can be increased.

(5.1.2) Battery Blower ON/OFF Switching Processing

Next, referring to FIGS. 15 and 16, the battery blower ON/OFF switching processing will be explained below. FIG. 15 is a flow chart showing the first half of the processing of switching ON/OFF of the battery blower, and FIG. 16 is a flow chart showing the second half of the processing of switching ON/OFF of the battery blower. First of all, as shown in FIG. 15, battery temperature T_b inputted into the input section 141 is read in (step. S111). Next, it is judged whether or not battery temperature T_b is not more than battery temperature threshold value T_b—th (step S112). In the case where battery temperature T_b is not more than battery temperature threshold value T_b—th (step S112: Yes), it is further judged whether or not the battery cooling blower 115 (battery blower) is being driven (ON) (step S113). In the case where the battery cooling blower 115 (battery blower) is being stopped (OFF) (step S113: No), the program is returned to step S111, and battery temperature T_b is read in again. On the other hand, in the case where the battery cooling blower 115 is being driven (ON) (step S113: Yes), the battery cooling blower 115 is stopped (step S114), and the program is returned to step S111, and battery temperature T_b is read in again.

On the other hand, in the case where battery temperature T_b is higher than battery temperature threshold value T_b—th (step S112: No), it is further judged whether or not the battery cooling blower 115 is being driven (ON) (step: S115). In the case where the battery cooling blower 115 is stopped (OFF) (step S115: No), the battery cooling blower 115 is driven (step S116), and a battery blower level, which is calculated by the battery blower level calculating section 142, is read in (step S117). On the other hand, in the case where the battery cooling blower 115 is being driven (step S115: Yes), the battery blower level calculated by the battery blower level calculating section 142 is read in as it is (step S117). After the battery blower level has been read in, it is judged whether or not the state of the mode switching door 136 is the inside air mode (step S118).

In the case where the mode is not the inside air mode, that is, the mode is the cooling air mode (step S118: No), it is further judged whether or not the battery blower level, which is calculated by the battery blower level calculating section 142, is the minimum level (step S119). In the case where the battery blower level calculating section 142, is the minimum level (step S119: Yes), it is judged whether or not the processing to further decrease the battery blower level is going to be conducted (step S120). In the case where the processing to further decrease the battery blower level is not going to be conducted (step S120: No), or alternatively in the case where the aforementioned battery blower level is not the minimum level (step S119: No), the program is returned to step S119, and the processing is repeated. On the other hand, in the case where the battery blower level is the minimum level and the processing to further decrease the battery blower level is going to be conducted (step S120: Yes), as shown in FIG. 16, the battery cooling blower 115 is stopped (step S121). That is, under the condition of the cooling air mode, in the case where the battery blower level is the minimum level and the battery 103 is sufficiently cooled, the battery cooling blower 115 is stopped as a preprocess.

In this connection, in the case where the state of the mode switching door 136 is the inside air mode (step S118: Yes) after the battery blower level has been read in, it is further judged whether or not the battery blower level, which is calculated by the battery blower level calculating section 142, is the maximum level (step S122). In the case where the battery blower level is the maximum level (step S122: Yes), it is judged whether or not the processing to further increase the battery blower level is going to be conducted (step S123). In the case where the processing to further increase the battery blower level is not going to be conducted (step S123: No) or alternatively in the case where the aforementioned battery blower level is not the maximum level (step S122: No), the program is returned to step S122, and the processing is repeated. On the other hand, in the case where the battery blower level is the maximum level and the processing to further increase the battery blower level is going to be conducted (step S123: Yes), it is judged whether or not the air conditioner is being driven (step S124). In the case where the air conditioner is stopped (OFF) (step S124: Yes), the air conditioner is forcibly driven (step S125), and the battery cooling blower 115 is stopped (step S121). On the other hand, in the case where the air conditioner is being driven (step S124: Yes), the battery cooling blower 115 is stopped as it is (step S121). That is, in the state of the inside air mode, in the case where the battery blower level is the maximum level and the battery is not sufficiently cooled, the battery cooling blower 115 is stopped as a preprocess of switching the mode to the cooling air mode.

Further, after the battery cooling blower 115 has been stopped, as shown in FIG. 16, a signal of the completion of OFF of the battery blower is outputted to the mode switching control section 144 (step S126). Then, it is judged whether or not the signal of the completion of switching the mode, which is outputted from the mode switching control section 144, is inputted (step S127), that is, it is judged whether or not switching the mode is completed. In this case, switching the mode is defined as follows. In the case of the inside air mode, the mode is switched to the cooling air mode. In the case of the cooling air mode, the mode is switched to the inside air mode. In the case where the signal of the completion of switching the mode is not inputted (step S127: No), that is, in the case where switching the mode is not completed, the processing to return to step S126 is repeated until switching the mode is completed. On the other hand, in the case where the signal of the completion of switching the mode is inputted (step S127: Yes), the battery cooling blower 115, which is being stopped, is driven (step S128).

(5.1.3) Battery Blower Level Change Rate Control Processing

Next, referring to FIG. 17, the battery blower level change rate control processing will be explained as follows. FIG. 17 is a flow chart showing the process of controlling a battery blower level changing rate. First, as shown in FIG. 17, conditioned air blowout temperature T_a inputted into the input section 141 is read in (step S131), and the value is represented by T1 (step S132). Then, it is judged whether or not the battery blower level calculated by the battery blower level calculating section 142 is changed (step S133). In the case where no change is caused in the battery blower level (step S133: No), the program is returned to step S131 and the processing is repeated. On the other hand, in the case where a change is caused in the battery blower level (step S133: Yes), the conditioned air blowout temperature T_a immediately after the battery blower level has been changed is read in (step: S134), and the thus read value is represented by T2 (step S135). Successively, it is judged whether or not |T2−T1|≦2° C. (step S136). In this case, |T2−T1| is a difference in temperature between conditioned air blowout temperature T1 immediately before the battery blower level, which is read in in step S132, is changed and conditioned air blowout temperature T2 immediately after the battery blower level, which is read in in step S134, is changed. That is, in step S136, it is judged whether or not a difference between the conditioned air blowout temperature before the battery blower level is changed and the conditioned air blowout temperature after the battery blower level has been changed is not more than 2° C. In the case where the temperature difference between T1 and T2 is not more than 2° C. (step S136: Yes), it is judged by the battery blower level calculating section 142 whether or not the change in the battery blower level has been completed (step S138). On the other hand, in the case where the temperature difference between T1 and T2 is larger than 2° C. (step S136: No), a changing rate of the battery blower level is reduced (step S137). Further, it is judged whether or not the change in the battery blower level is completed (step S138). In this connection, when the conditioned air blowout temperature is changed in a short period of time in which the difference between the conditioned air blowout temperature before the battery blower level is changed and the conditioned air blowout temperature after the battery blower level has been changed exceeds 3° C. or more, a passenger has a feeling of discomfort. Therefore, in step S137, in order to prevent the passenger from having a feeling of discomfort, at the point of time when the difference in the conditioned air blowout temperature exceeds 2° C., the changing rate of the battery blower level is reduced in this processing.

In step S138, in the case where the change in the battery blower level is completed (step S138: Yes), the processing is ended as it is. On the other hand, in the case where the change in the battery blower level is not completed (step S138: No), the program is returned to step S134 and the processing is repeated.

(5.2) Mode Switching Control Processing

Referring to FIG. 18, the mode switching control processing is explained below. FIG. 18 is a flow chart showing the processing of switching control of the mode. As shown in FIG. 18, the mode switching door 136 is initially set at the inside air mode (step S141). Next, it is judged whether or not there is an input signal of the completion of OFF of the battery blower which is outputted from the battery blower control section 143 (step S142). In the case where there is no input signal of the completion of OFF of the battery blower (step S142: No), the processing is repeated until the input signal of the completion of OFF of the battery blower is obtained (step S142: Yes). Further, it is judged whether or not the state of the mode switching door 136 is the inside air mode (step S143). In the case where the state of the mode switching door 136 is not the inside air mode, that is, in the case where the state of the mode switching door 136 is the cooling air mode (step S143: No), the mode is switched to the inside air mode (step S144), and a signal of the completion of switching the mode is outputted (step S146). On the other hand, in the case of the inside air mode (step S143: Yes), the mode is switched to the cooling air mode (step S145), and a signal of the completion of switching the mode is outputted (step S146). In this connection, at the time of switching the mode, the mode switching control section 144 controls so that the closing rate of closing the mode switching door 136 can be lower than the opening rate as described before. After a signal of the completion of switching the mode has been outputted, the program is returned to step S142 and the processing is repeated.

In this connection, the signal of the completion of OFF of the battery blower in step S142 is a signal outputted in step S126 in which ON/OFF switching of the battery blower is conducted in the battery blower level control section 143 after the cooling blower 115 is stopped (shown in FIG. 16). When the battery cooling blower 115 is stopped before the mode is switched (step S121 in FIG. 16), it is possible to reduce an intensity of noise level generated at the time of switching the mode. Under the condition that the battery cooling blower 115 is stopped, the mode is switched (steps S144 and S145), and a signal of the completion of switching the mode is outputted as described above (step S146). When this signal of the completion of switching the mode is inputted into the battery blower control section 143, the battery cooling blower 115, which is being stopped before the mode is switched, is driven again (step S128 in FIG. 16).

(5.3) Air Conditioning Blower Level Calculation Correction Control Processing

Referring to FIG. 19, the air conditioning blower level calculation correction control processing will be explained below. FIG. 19 is a flow chart showing the air-conditioning blower level calculation correction control processing. First of all, as shown in FIG. 19, TAO is read in which is calculated by Expression 1 in TAO calculating section 145 (step S151). Next, according to TAO, the air-conditioning blower level is calculated (step S152). Then, it is judged whether or not the mode switching door 136 is in the cooling air mode (step S153). In the case where the mode switching door 136 is in the cooling air mode (step S153: Yes), the air-conditioning blower level is corrected (step S154), and further the air-conditioning blower level control is conducted (step S155). On the other hand, in the case where the mode switching door 136 is in the inside air mode (step S153: No), the air-conditioning blower level control is conducted as it is (step S155). Then, the program is returned to step S151, and the series of processes is repeated.

(5.4) Air Mixing Door Opening Degree Calculation Correction Control Processing

Next, referring to FIG. 20, the air mixing door opening degree calculation correction control processing will be explained below. FIG. 20 is a flow chart showing the air-mixing door opening degree calculation correction control processing. First, as shown in FIG. 20, TAO calculated by Expression 1 in TAO calculating section 145, T_e (after-evaporator temperature) inputted into the input section 141 and T_w, (cooling water temperature) are read in (step S161). Next, the air mixing door opening degree is calculated by Expression 2 in the air mixing door opening degree calculating section 146 (step S162). Then, it is judged whether or not the mode switching door 136 is in the cooling air mode (step S163). In the case where the mode switching door 136 is in the cooling air mode (step S163: Yes), the air mixing door opening degree is corrected (step S164) and, further, the air mixing door opening degree control is conducted (step S165). On the other hand, in the case where the mode switching door 136 is in the inside air mode (step S163: No), the air mixing door opening degree control is conducted as it is (step S165). Then, the program is returned to step S161 and the series of processing is repeated.

Finally, another embodiment will be explained as follows. In the above embodiment, immediately before the mode switching door 136 is opened, the battery cooling blower 115 is stopped (OFF), and immediately after the mode switching door 136 is closed, the battery cooling blower 115 is driven (ON). However, the present invention is not limited to the above specific embodiment. For example, before the mode switching door 136 is opened, the battery blower level may be decreased to a predetermined level, and after the mode switching door 136 is closed, the battery blower level may be gradually increased. In this case, the predetermined level is a battery blower level corresponding to a level (for example, a level not more than 30 dB in any noise level) at which no passenger hears noise generated by the friction between the mode switching door 136 and the battery blowing cooling air caused at the time of opening and closing the mode switching door 136.

Further, in the above embodiment, the evaporator side duct 114 is communicated with the downstream side of the evaporator 123 of one side passage in which the evaporator 123 is arranged in the air-conditioning case 121. However, the present invention is not limited to the above specific embodiment. For example, the evaporator side duct 114 may be communicated with the downstream side of the evaporator in the air-conditioning case of the front seat side air-conditioning unit (not shown) arranged on the front seat side. That is, the cooling air may be introduced to the battery casing 111 side from the front seat side air-conditioning unit when the air conditioner for vehicle use is in the cooling air mode.

While the invention has been described by reference to specific embodiments chosen for purposes of illustration, it should be apparent that numerous modifications could be made thereto by those skilled in the art without departing from the basic concept and scope of the invention.

Claims

1. A battery cooling device, cooling a battery for vehicle use, applied to a vehicle on which an air conditioner having a cooling means for cooling air passing through the cooling means is mounted, comprising:

a battery cooling blower for blowing suction air to the battery for vehicle use; and

a mode switching means capable of switching a mode among an inside air mode in which the suction air is the air inside a vehicle passenger compartment, an outside air mode in which the suction air is the air outside a vehicle passenger compartment and a cooling air mode in which the suction air is the air cooled by the cooling means of the air conditioner.

2. A battery cooling device for vehicle use according to claim 1, wherein the air outside the vehicle passenger compartment is the air in a trunk.

3. A battery cooling device for vehicle use according to claim 1, wherein the mode switching means switches the mode in the order of the outside air mode, the inside air mode and the cooling air mode.

4. A battery cooling device for vehicle use according to claim 3, wherein the mode switching means switches a mode in the order of the outside air mode, the inside air mode and the cooling air mode according to the temperature of the battery for vehicle use in the case where the temperature outside the vehicle passenger compartment is not more than a predetermined value, and

the mode switching means switches a mode in the order of the inside air mode and the cooling air mode according to the temperature of the battery for vehicle use in the case where the temperature outside the vehicle passenger compartment is higher than the predetermined value.

5. A battery cooling device for vehicle use according to claim 1, wherein the mode switching means switches a mode among the inside air mode, the outside air mode and the cooling air mode according to the temperature of the air outside the vehicle passenger compartment and the temperature of the battery for vehicle use.

6. A battery cooling device for vehicle use according to claim 1, wherein the air conditioner mounted on a vehicle is a front seat side air conditioner arranged on the front seat side of the vehicle and a rear seat side air conditioner arranged on the rear seat side of the vehicle, and

the cooling air mode is a mode in which the suction air is the air cooled by the cooling means of the rear seat side air conditioner.

7. A battery cooling device cooling a battery for vehicle use, applied to a vehicle on which an air conditioner having a cooling means for cooling air passing through the cooling means is mounted, comprising:

a battery cooling blower for blowing suction air to the battery for vehicle use; and

a mode selecting means for selecting a suction mode of the battery cooling blower between the inside air mode, in which the air in the vehicle passenger compartment is sucked, and the cooling air mode in which the air immediately after it is cooled by the cooling means is sucked.

8. A battery cooling device for vehicle use according to claim 7, further comprising:

an outside air temperature detection means for detecting a temperature outside the vehicle; and

a battery temperature detection means for detecting a temperature of the battery, wherein

the mode selecting means selects a suction mode between the inside air mode and the cooling air mode according to the temperature of the air outside the vehicle detected by the outside air temperature detection means and also according to the temperature of the battery detected by the battery temperature detection means.

9. A battery cooling device for vehicle use according to claim 8, wherein the mode selecting means selects a suction mode between the inside air mode and the cooling air mode according to the temperature of the battery in the case where the temperature of the air outside the vehicle is higher than a predetermined temperature, and the mode selecting means selects the inside air mode in the case where the temperature of the air outside the vehicle is not more than the predetermined temperature.

10. A battery cooling device for vehicle use according to claim 9, wherein the mode selecting means selects the inside air mode in the case where the battery temperature is lower than a reference temperature when the temperature of the air outside the vehicle is higher than the predetermined temperature, the mode selecting means selects the cooling air mode in the case where the battery temperature is not less than the reference temperature, and the reference temperature is decreased as the temperature of the air outside the vehicle is increased.

11. A battery cooling device for vehicle use according to claim 7, wherein the air conditioner mounted on the vehicle includes a front seat side air conditioner arranged on the front seat side and a rear seat side air conditioner arranged on the rear seat side of the vehicle, and

the air immediately after it is cooled by the cooling means of the rear seat side air conditioner is sucked in the cooling air mode.

12. A battery cooling device for vehicle use according to claim 7, wherein the mode selecting means selects a mode in which the air in the vehicle passenger compartment is sucked together with the air immediately after it is cooled by the cooling means at the time of the cooling air mode.

13. A battery cooling device cooling a battery for vehicle use, applied to a vehicle on which an air conditioner having a cooling means for cooling air passing through the cooling means is mounted, comprising:

a battery cooling blower for blowing suction air to the battery for vehicle use; and

a mode selecting means for selecting a suction mode of the battery cooling blower among the inside air mode, in which the air in the vehicle passenger compartment is sucked, the cooling air mode, in which the air immediately after it is cooled by the cooling means is sucked, and a mixed air mode in which both the air in the vehicle passenger compartment and the air immediately after it is cooled by the cooling means are sucked.

14. A battery cooling device for vehicle use according to claim 13, further comprising:

an outside temperature detection means for detecting the temperature of the air outside the vehicle; and

a battery temperature detection means for detecting the battery temperature, wherein

the mode selecting means selects a suction mode among the inside air mode, the cooling air mode and the mixed air mode according to the temperature of the air outside the vehicle detected by the outside air temperature detection means and also according to the temperature of the battery detected by the battery temperature detection means.

15. A battery cooling device for vehicle use according to claim 14, wherein the mode selecting means selects a suction mode among the inside air mode, the cooling air mode and the mixed air mode according to the temperature of the battery in the case where the temperature of the air outside the vehicle is higher than a predetermined temperature, and the mode selecting means selects the inside air mode in the case where the temperature of the air outside the vehicle is not more than the predetermined temperature.

16. A battery cooling device for vehicle use according to claim 15, wherein the mode selecting means selects the inside air mode when the battery temperature is lower than the first reference temperature in the case where the temperature of the air outside the vehicle is higher than the predetermined temperature, the mode selecting means selects the cooling air mode when the battery temperature is not less than first reference temperature and lower than the second reference temperature and the mode selecting means selects the mixed air mode when the battery temperature is not less than the second reference temperature, and

at least one of the first and the second reference temperature or both the first and the second reference temperature are lowered as the temperature of the air outside the vehicle is raised.

17. A battery cooling device for vehicle use according to claim 14, wherein the air conditioner mounted on the vehicle includes a front seat side air conditioner arranged on the front seat side and a rear seat side air conditioner arranged on the rear seat side of the vehicle, and

the air immediately after it is cooled by the cooling means of the rear seat side air conditioner is sucked in the cooling air mode and the mixed air mode.

18. An air conditioner for vehicle use comprising:

an air-conditioning unit including a cooling air generation means for generating cooling air by cooling the passing air, a heating air generation means for generating heating air by heating the passing air, a conditioned air generation means for generating conditioned air by mixing the cooling air and the heating air by a ratio of the hot air to the cold air, and an air-conditioning blower for generating conditioned blowout air blowing out to a passenger in a vehicle passenger compartment;

a battery cooling unit including a battery cooling blower, which sucks the cooling air, for generating a flow of battery cooling air to be blown out to a battery mounted on a vehicle; and

a control unit including a conditioned air ratio calculating means for calculating a ratio of the hot air to the cold air, a correction means for correcting at least one of the ratio of the hot air to the cold air and the conditioned air volume level according to the battery cooling air volume level, a conditioned air volume level control means for controlling a conditioned air volume level which is the air volume level of the conditioned air blown out, and a battery air volume level control means for controlling a battery cooling air volume level which is an air volume level of the battery cooling air blown out.

19. An air conditioner for vehicle use according to claim 18, wherein the correction means for correcting the ratio of the hot air to the cold air conducts a correction so that a ratio of the cooling air in the conditioned air can be increased according to an increase in the battery cooling air volume level.

20. An air conditioner for vehicle use according to claim 18, wherein the correction means for correcting the conditioned air volume level conducts a correction so that the conditioned air volume level can be increased according to an increase in the battery cooling air volume level.

21. An air conditioner for vehicle use comprising:

an air-conditioning unit including a cooling air generation means for generating cooling air by cooling the passing air, a heating air generation means for generating heating air by heating the passing air, a conditioned air generation means for generating conditioned air by mixing the cooling air and the heating air by a ratio of the hot air to the cold air, an air-conditioning blower for generating conditioned blowout air blowing out to a passenger in a vehicle passenger compartment, and a conditioned air blowout temperature detection means for detecting a conditioned air blowout temperature which is a temperature of the conditioned blowout air;

a battery cooling unit including a battery cooling blower for generating a flow of battery cooling air to be blown out to a battery mounted on a vehicle, and a mode switching means for switching a mode between the inside air mode, in which the sucked air is the inside air in the vehicle passenger compartment according to the battery temperature, and the cooling air mode in which the suction air is the cooling air; and

a control unit including a conditioned air ratio calculating means for calculating the ratio of the hot air to the cold air, a conditioned air volume level control means for controlling a conditioned air volume level which is an air volume level of the conditioned blowout air, and a battery air volume level control means for controlling a battery cooling air volume level which is an air volume level of the battery cooling blowout air, wherein

the battery air volume level control means reduces the battery cooling air volume level to a value not more than the predetermined value at the time of switching the mode, and the battery air volume level control means further reduces a change rate of the battery cooling air volume level in the case where the change rate of the conditioned blowout air temperature exceeds the predetermined value.

22. An air conditioner for vehicle use according to claim 21, wherein the battery air volume level control means stops the battery cooling blower at the time of switching the mode.

23. An air conditioner for vehicle use according to claim 21, wherein the mode switching means is capable of adjusting a switching rate of switching the mode.