Abstract: In a refrigerant cycle system, a gas-liquid separator has a gas-suction pipe for introducing gas refrigerant from the gas-liquid separator to a compressor. The gas-suction pipe has an open end opened in a gas-refrigerant area in the gas-liquid separator, a first suction hole, provided in a liquid-refrigerant area of the gas-liquid separator, for sucking liquid refrigerant containing lubricating oil, and a second suction hole provided in the gas-refrigerant area of the gas-liquid separator. The second suction hole for sucking gas refrigerant is formed in the gas-suction pipe at a downstream refrigerant side of the first suction hole. Therefore, a flow rate of gas refrigerant passing through around the first suction hole in the gas-suction pipe is decreased due to introduction of gas refrigerant by the second suction hole, thereby decreasing quantity of liquid refrigerant sucked from the first suction hole.

Abstract: A refrigerant cycle system includes a gas-liquid separator for separating gas-liquid refrigerant into gas refrigerant and liquid refrigerant. The gas-liquid separator has a liquid-suction pipe for introducing liquid refrigerant from the gas-liquid separator to a decompressing unit, and a gas-suction pipe for introducing gas refrigerant from the gas-liquid separator to a compressor. The gas-suction pipe has a suction hole for sucking liquid refrigerant therein, and the suction hole is provided at a position lower than an open end of the liquid-suction pipe. Because a height of a surface of liquid refrigerant in the gas-liquid separator is constantly equal to or higher than the open end of the liquid-suction pipe regardless of change in a heating load of the refrigerant cycle, liquid refrigerant is constantly sucked into the gas-suction pipe from the suction hole.

Abstract: The evaporator and the condenser are disposed in a duct. First bypass passage is disposed at the side of the condenser and first air mixing damper rotates to control air bypassing amount. Further second bypass passage is formed at the side of the evaporator and second mixing damper rotates to control air bypassing amount. Cooling rate at the evaporator and heating rate at the condenser are varied so that air adjusted in proper temperature is generated and discharged from each outlets into a room. An outside heat exchanger is disposed the outside of the duct. Refrigerant flow is randomly switched among the outside heat exchanger, the evaporator and the condenser so that cooling, heating, dehumidifying, dehumidified-heating and defrosting operations are performed.

Abstract: A control apparatus for a gas injection type air conditioning system that prevents lowering of compressor speed and cycle stoppage under conditions where high pressure is liable to occur. During a system heating mode, a pressure change rate ASP of the high pressure of the refrigerating cycle is calculated. When a pressure change rate .increment.SP rises above a predetermined value, a system electric expansion valve aperture is reduced. Accordingly, by calculation of the pressure change rate .increment.SP, it is possible to control the electric expansion valve in the above manner earlier than in prior art control schemes when there is a sudden rise in the high pressure.

Abstract: The waste heat from a heating part mounted on a vehicle is recovered and extracted by a refrigerant for gas injection so that the heating capacity at a low ambient temperature may be effectively improved while suppressing an increase in the power consumption. At the heating time, the refrigerant is circulated in a closed circuit composed of a compressor, an indoor heat exchanger, a pressure regulator and an outdoor heat exchanger, and the refrigerant, as condensed in the indoor heat exchanger, is regulated to an intermediate pressure by a pressure regulator and introduced into a heat exchanger. In this heat exchanger, the refrigerant extracts the heat from the heating part at the side of the vehicle so that it evaporates. The refrigerant thus having evaporated is introduced through an evaporation pressure regulating valve via a gas injection passage into a gas injection port of the compressor.

Abstract: An automotive air conditioner which conditions air making use of radiation of heat of a condenser and absorption of heat of an evaporator effectively. The evaporator 207 and the condenser 203 are disposed in a duct 100. A bypass passageway 150 is provided sidewardly of the condenser 203 in the duct 100, and a flow rate of air bypassing the condenser 203 is controlled by pivotal motion of an air mixing damper 154. Another bypass passage is provided sidewardly of the evaporator 207 in the duct 100, and a flow rate of air bypassing the evaporator 207 is controlled by pivotal motion of a bypass damper 159. Air is conditioned to an optimum blown out air temperature by varying the cooling rate at the evaporator 207 and the heating rate at the condenser 203 and is blown out to a room of an automobile from spit holes 141, 142 and 143.

Abstract: In the cooling operation, it is determined whether supplied electric current (IDC) supplied to an electric motor for driving a compressor is less than a predetermined value or not, that is, whether consumed electric power of the electric motor is less than a predetermined value or not. In the cool-down control, the determination may be "NO", however, in this case an inverter is controlled so that the IDC is set to the predetermined value. Thus, in the present invention, since IDC is always the predetermined value a1 or less and the consumed electric power of the electric motor is always the predetermined value or less, coefficiency of performance (COP) of the refrigerating cycle can be maintained to a predetermined magnitude.

Abstract: According to the present invention, when the inside air circulation mode is determined, the blower for blowing air to the heat exchanger is operated with the regular blower voltage. When the outside air introduction mode is determined, the blower is operated with the lower blower voltage lower than the regular blower voltage. As a result, consumed electric power of a compressor in the outside air introduction mode can be controlled and the deterioration of the efficiency of the refrigerating cycle in the inside air circulation mode can be prevented.

Abstract: According to the present invention, in a heating operation where a heating indoor heat exchanger function as a condenser and an outdoor heat exchanger functions as an evaporator, an air amount supplied by a blower is reduced when a predetermined amount of frost is or may be deposited on the outdoor heat exchanger in an outside air introduction mode where an outside air is supplied into a passenger compartment. Accordingly, a heating load is reduced to thereby reduce an endothermic amount in the outdoor heat exchanger. As a result, a frost deposition speed is reduced, and a deposited frost limit is increased, thereby extending a heating operation period.

Abstract: In the heating operation mode, the condensed temperature is calculated by the value of the discharged pressure sensor disposed at the discharge side of the compressor. Based on a difference between the condense temperature and a value of the outlet temperature sensor for detecting the refrigerant having passed through the heating indoor heat exchanger, the supercooling degree is calculated. Then, an opening degree of the expansion valve for heating is controlled so that the calculated supercooling degree is set to a target supercooling degree. Thus, since the condensed temperature is calculated by employing a high responsive pressure sensor, an error in the calculation of the condensed temperature can be reduced, thereby reducing an error in the calculation of the supercooling degree.

Abstract: The evaporator and the condenser are disposed in a duct. First bypass passage is disposed at the side of the condenser and first air mixing damper rotates to control air bypassing amount. Further second bypass passage is formed at the side of the evaporator and second mixing damper rotates to control air bypassing amount. Cooling rate at the evaporator and heating rate at the condenser are varied so that air adjusted in proper temperature is generated and discharged from each outlets into a room. An outside heat exchanger is disposed the outside of the duct. Refrigerant flow is randomly switched among the outside heat exchanger, the evaporator and the condenser so that cooling, heating, dehumidifying, dehumidified-heating and defrosting operations are performed.

Abstract: When a defroster switch is input in a heating operation mode, an opening degree of an electric type of a heating expansion valve is controlled to be smaller when temperature of refrigerant discharged from a compressor is less than a predetermined temperature. Therefore, the supercooling degree of the liquid refrigerant of an indoor heating heat exchanger becomes large, the temperature of the heat exchanger becomes high, so that the temperature of air which is blown from a defroster outlet becomes high. Thus, the defrosting effect of a front windshield glass can be increased. Accordingly, when the defrosting of the front windshield is needed, the defrosting effect is increased as compared with when the defrosting is not needed.

Abstract: An automotive air conditioner which conditions air making use of radiation of heat of a condenser and absorption of heat of an evaporator effectively. The evaporator 207 and the condenser 203 are disposed in a duct 100. A bypass passageway 150 is provided sidewardly of the condenser 203 in the duct 100, and a flow rate of air bypassing the condenser 203 is controlled by pivotal motion of an air mixing damper 154. Another bypass passage is provided sidewardly of the evaporator 207 in the duct 100, and a flow rate of air bypassing the evaporator 207 is controlled by pivotal motion of a bypass damper 159. Air is conditioned to an optimum blown out air temperature by varying the cooling rate at the evaporator 207 and the heating rate at the condenser 203 and is blown out to a room of an automobile from spit holes 141, 142 and 143.

Abstract: An automotive air conditioner which conditions air making use of radiation of heat of a condenser and absorption of heat of an evaporator effectively. The evaporator 207 and the condenser 203 are disposed in a duct 100. An condenser disposed in a duct has a heat exchanging section in which heat exchange is performed between refrigerant and draft air. The heat exchanging section is divided into an upper stream area portion, a middle stream area portion and a lower stream area portion, and a temperature sensitive tube of a subcooling control valve is held in contact with a refrigerant passageway which interconnects the middle and lower stream area portions. The subcooling control valve adjusts the opening of a throttle portion thereof so that the subcooling degree on the upstream of the lower stream area portion where the temperature sensitive tube contacts may be a predetermined value (2.degree. to 10.degree. C.).

Abstract: An air conditioning system that can operate an air conditioner of an electric vehicle without interfering with the charging process, which utilizes a secondary battery. When operation of the vehicle is terminated and the control system determines that a frosting judgment decision is positive, the control system judges whether the charging current has dropped to a specified level or less. As soon as the charging current has dropped to or below the specified level, the excess charging current may be used for a defrosting operation. When the operation of the vehicle is stopped and the control system determines that a frosting judgment decision is negative, the control system judges whether a preliminary air conditioning switch is on. If the preliminary air conditioning switch is on, it is judged whether charging of the secondary battery is in progress. If charging is progressing, the control system determines whether the charging current has dropped to or below a specified level.

Abstract: The invention prevents the temperature of supplied air from being decreased by a defrosting operation when a vehicle is in operation. During the heating operation, it is judged whether the vehicle is in operation. When the vehicle is in operation, it is judged whether an external heat exchanger is frosted or not relying upon the external air temperature, temperature of the external heat exchanger (coolant) and the time of heating operation. When it is judged that frost is formed, the rotational speed of the compressor is increased to increase the ability to supplying the coolant, to maintain heating ability and to prevent the drop of temperature of the supplied air. When the frost is formed after the operation of the vehicle has been finished, it is judged whether the secondary batteries are being charged or not, i.e., whether the charging circuit of the secondary batteries is connected to the external power source for charging or not.

Abstract: An air-conditioning apparatus that prevents a state of blowing temperature fluctuation due to magnitude of vehicle speed in a dehumidification mode. A condenser and evaporator are disposed within an air duct, and an exterior heat exchanger is disposed externally. A capillary and check valve are provided in a refrigerant passage between the condenser and exterior heat exchanger, and a capillary is provided in a refrigerant passage between the exterior heat exchanger and evaporator. During dehumidification mode, a four-way switching valve is switched so that the flow passage of refrigerant is from the condenser to the capillary, to the check valve, to the exterior heat exchanger, to the capillary, to the evaporator, and then to an accumulator. In this case, the condenser and exterior heat exchanger function as a refrigerant condenser in a series-connected state, but because in actuality the capillary is provided, the majority of refrigerant discharged from a compressor is condensed by the condenser.

Abstract: An air conditioning apparatus for heating a cabin of an electric car having reduced electric power consumption is disclosed. An initial setting of the heating operation is that of using a refrigerating cycle 17. An average value of actual electric power consumption using the refrigerating cycle for a predetermined period is calculated. Furthermore, electric power consumption using an electric heater 20 is calculated for obtaining the same heating capacity as that obtained by the refrigerating cycle. A switching of the heating operation from the refrigerating cycle to the electric heater 20 takes place when it is determined that electric power consumption using the electric heater is less than that using the refrigerating cycle 17.

Abstract: An air conditioning apparatus suitable for an electric powered automobile, where at least one of a heating and a dehumidifying operation is effected by utilizing a refrigerating cycle. An upstream heat exchanger and a downstream heat exchanger are arranged in a duct through which air passes for air conditioning. An outside heat exchanger with an outside fan are further provided, which act as a condenser in a cooling mode, although a refrigerant passes therethrough when using the heating and the dehumidifying modes. Upon use of a dehumidifying mode, the upstream heat exchanger acts as an evaporator, while the downstream heat exchanger acts as a condenser. The temperature of the refrigerant sensed by a temperature sensor at the outlet of the compressor if higher than a predetermined value (110.degree. C.

Abstract: An automotive air conditioner comprises a refrigerating unit including a compressor, for carrying out a refrigerating cycle, and a temperature regulator for setting the temperature of air to be blown into the passenger compartment of an automobile. The rotating speed of the compressor, hence the flow rate of the refrigerant, is regulated by controlling an inverter for controlling an electric motor for driving the compressor according to a temperature set by the temperature regulator. The automatic air conditioner is suitable for use on an electric motorcar.