RIDING TYPE VEHICLE
A riding type vehicle has a driving source, a left wheel and a right wheel, a transmission configured to receive power from the driving source to independently operate and drive the left wheel and the right wheel with regard to a rotation direction and a rotation speed, and caster wheels separately provided in a front-rear direction with respect to the left wheel and the right wheel, the riding type vehicle including two first sensors arranged on both left and right sides more to a front side than a rear end of the vehicle, the two first sensors configured to detect an obstacle target located on a rear side, the obstacle target being a target becoming an obstacle at the time of reversing or turning.
The entire disclosures of Japanese Patent Application No. 2016-070103, Japanese Patent Application No. 2016-071091, Japanese Patent Application No. 2016-071132, and Japanese Patent Application No. 2016-071163, filed on Mar. 31, 2016 including the specification, claims, drawings, and abstract are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION 1. Field of the InventionThe present invention relates to a riding type vehicle that includes a driving source, a left wheel and a right wheel capable of being independently driven with regard to a rotation direction and a rotation speed, and caster wheels separately provided in a front-rear direction with respect to the left wheel and the right wheel.
2. Description of the Related Art(s)
Lawnmower vehicles that include a lawnmower driven for performing lawn mowing work are conventionally known. Moreover, lawnmower vehicles that include a left wheel and a right wheel, which are main driving wheels independently travel-driven by respective motors such as electric motors or hydraulic motors, and caster wheels, can also be considered in such lawnmower vehicles.
Moreover, as lawnmower vehicles, there are lawnmower vehicles capable of self-travel that perform travelling and control of lawn mowing on the vehicle ridden by a driver, and these are called riding lawnmower vehicles. For example, as lawnmowers there are propeller-type rotation blade type and rotation winding blade type lawnmower rotating tools or the like.
A riding lawnmower vehicle is used entirely in a so-called off-road situation such as in a garden, and moves on the ground surface for lawn mowing work.
For example, Japanese Patent Application Publication No. 2006-507789 (corresponding to US publication No. 2004-0134175) describes a hybrid power device equipped with an engine-dynamo combined unit that connects a rotor to an engine shaft of an internal combustion engine. A lawnmower vehicle illustrated as a power device is described as having independent electric motors respectively connected to multiple driving wheels, the respective driving wheels can be independently controlled at variable speeds, and smooth starting, stopping, speed variation, and direction switching can be performed for such a lawnmower vehicle. FIG. 4 and the description of FIG. 4 in Japanese Patent Application Publication No. 2006-507789 (corresponding to US publication No. 2004-0134175) describe a riding lawnmower vehicle capable of turning with a zero rotation radius.
In the case of the vehicle described in FIG. 4 and the description of FIG. 4 in Japanese Patent Application Publication No. 2006-507789 (corresponding to US publication No. 2004-0134175), a turn is made possible by having the speeds of the left and right rear wheels differ. In such a vehicle, a rapid turn can be performed with a small rotation radius. In this case, a driver performs a turn to the rear while looking back to the rear. However, in the case where there is an obstacle target in a region that becomes a blind spot with respect to the driver's visual field, there is a possibility that this obstacle target will not be able to be confirmed. In particular, at the time when there is an obstacle target, which is a person or object on the outer side in the left-right direction, there is a possibility that this obstacle target will not be able to be confirmed, more to the rear than the driver's seat of the vehicle and more to the front than the rear end of the vehicle. As a result, it is desirable to implement a configuration where it is easy to automatically detect an obstacle target, at the time of turning travel to the rear. Moreover, in a configuration of a vehicle capable of a rapid turn, where only one of the left wheel and the right wheel rotates around a turn center position, or the left wheel and the right wheel rotate in opposite directions, it will become easy for the vehicle to approach an obstacle target, which is a person or object positioned in a difficult-to-confirm position in a surrounding part, at the time of a rapid turn to the rear. Also, considerable attention is required by the driver in order to avoid colliding with an obstacle target. As a result, it is desirable to implement a configuration where it is easy to automatically avoid a collision with an obstacle target at the time of a rapid turn to the rear.
If an obstacle target can be automatically detected at the time of turning travel to the rear, for example, it will be easy to avoid colliding with the obstacle target. Moreover, in a lawnmower vehicle, there is the possibility that an obstacle target will be wound around the lawnmower, by having the obstacle target be near the lawnmower at the time of turning travel to the rear. If an obstacle target can be automatically detected at the time of turning travel to the rear, it will be easy to avoid the obstacle target being wound around the lawnmower at the time of turning travel to the rear.
Moreover, in the vehicle described in FIG. 4 and the description of FIG. 4 in Japanese Patent Publication Application No. 2006-507789 (corresponding to US publication No. 2004-0134175), a rapid turn with a small rotation radius is possible by causing only one of the left wheel and the right wheel to rotate, or causing the left wheel and the right wheel to rotate in opposite directions. However, in the case where rapidly turning, it is possible for unstable turning to be performed, where the behavior of the vehicle becomes unstable due to a high turning speed or the like, by the operation of a driver. While such an unstable turn is based on the operation by the driver, it is not desirable from the viewpoint of safe travelling of the vehicle. As a result, a structure is desirable that can automatically suppress an unstable turn of the vehicle.
SUMMARY OF THE INVENTIONAt least one advantage of the present invention, in a configuration of a riding type vehicle where left and right wheels are capable of being independently driven with regard to a rotation direction and a rotation speed, is that it is possible to implement a configuration where it is easy to automatically detect an obstacle target that approaches the vehicle at the time of turning travel to the rear.
At least one advantage of the present invention, in a configuration of a riding type vehicle where left and right wheels are capable of being independently driven with regard to a rotation direction and a rotation speed, is that it is possible to implement a configuration where it is easy to automatically avoid colliding with an obstacle target at the time of a rapid turn to the rear.
At least one advantage of the present invention, in a configuration of a riding type vehicle where left and right wheels are capable of being independently driven with regard to a rotation direction and a rotation speed, is it is possible to implement a configuration where an unstable turn may be automatically suppressed.
A first riding type vehicle according to the present invention has a driving source, a left wheel and a right wheel, a transmission configured to receive power from the driving source to independently operate and drive the left wheel and the right wheel with regard to a rotation direction and a rotation speed, and caster wheels separately provided in a front-rear direction with respect to the left wheel and the right wheel, the first riding type vehicle including two first sensors arranged on both left and right sides more to a front side than a rear end of the vehicle, the two first sensors configured to detect an obstacle target located on a rear side, the obstacle target being a target becoming an obstacle at the time of reversing or turning.
A second riding type vehicle according to the present invention has a driving source, a left wheel and a right wheel, a transmission configured to receive power from the driving source to independently operate and drive the left wheel and the right wheel with regard to a rotation direction and a rotation speed, and caster wheels separately provided in a front-rear direction with respect to the left wheel and the right wheel, wherein the second riding type vehicle is capable of a rapid turn where only one of the left wheel and the right wheel rotates around a turn center position, or the left wheel and the right wheel rotate in opposite directions, the second riding type vehicle including a sensor, arranged on the vehicle, capable of detecting an obstacle target on a rear side, the obstacle target being a target becoming an obstacle at the time of reversing or turning, and a control device for causing a rapid turn to the rear to stop, or causing a stop of a rapid turn to be maintained, at the time when the obstacle target has been detected by the sensor.
A third riding type vehicle according to the present invention has a driving source, a left wheel and a right wheel, a transmission configured to receive power from the driving source to independently operate and drive the left wheel and the right wheel with regard to a rotation direction and a rotation speed, and caster wheels separately provided in a front-rear direction with respect to the left wheel and the right wheel, wherein the third riding type vehicle is capable of a rapid turn where only one of the left wheel and the right wheel rotates around a turn center position, or the left wheel and the right wheel rotate in opposite directions, the third riding type vehicle including a sensor, arranged on the vehicle, capable of detecting an obstacle target on a rear side, the obstacle target being a target becoming an obstacle at the time of reversing or turning, and a control device for causing a turn to decelerate, at the time when the obstacle target has been detected by the sensor and a rapid turn is performed to the rear, and causing a turn to stop prior to the vehicle colliding with the obstacle target.
A fourth riding type vehicle according to the present invention has a driving source, a left wheel and a right wheel, a transmission configured to receive power from the driving source to independently operate and drive the left wheel and the right wheel with regard to a rotation direction and a rotation speed, and caster wheels separately provided in a front-rear direction with respect to the left wheel and the right wheel, wherein the fourth riding type vehicle is capable of a rapid turn where only one of the left wheel and the right wheel rotates, or the left wheel and the right wheel rotate in opposite directions, the fourth riding type vehicle including a rapid turn detection section for detecting the vehicle performing a rapid turn, and a turning speed suppression section for suppressing a turning speed when a rapid turn is being performed and a turning stability relationship amount, which is a physical quantity related to turning stability, is equal to or higher than a threshold.
Embodiment(s) of the present disclosure will be described based on the following figures, wherein:
Hereinafter, embodiments according to the present invention will be described in detail using the figures. Note that hereinafter, while a configuration will be mainly described where left and right wheels of a riding lawnmower vehicle are driven by hydraulic motors as motors for travelling, the motors for travelling may be other motors, such as electric motors. Hereinafter, while a case will be described where the wheels are arranged on the rear side as left and right main driving wheels, and caster wheels are arranged on the front side, the wheels may be on the front side and the caster wheels may be on the rear side.
The shape, number, and the arrangement relationships of parts or the like stated hereinafter are illustrations for the description, and arbitrary changes are possible, in accordance with the specifications or the like of the riding lawnmower vehicle. Moreover, hereinafter, the same reference numerals will be attached to similar elements in all of the figures, and overlapping descriptions will be omitted or simplified.
The vehicle 10 is a self-propelled type off-road vehicle suitable for lawnmowing. The vehicle 10 includes a left wheel 12 and a right wheel 13, caster wheels 15, 16, a lawnmower 18, two first sensors 50a, 50b, a tension switching actuator 43 (
The left wheel 12 and the right wheel 13 are rear wheels supported on both the left and right sides of the rear side of a main frame 20, which is a vehicle body, and are main driving wheels. The main frame 20 is formed in a beam structure or the like, by a metal such as steel. The main frame 20 includes side plate parts 20a, 20b extending in an approximately front-rear direction at both the left and right ends, and a connection part 20c that connects the side plate parts 20a, 20b of both the left and right sides. A driver's seat 21, on which a driver sits, is fixed on the upper side between the rear end parts of the left and right side plate parts 20a, 20b.
Left and right operation levers 22, 23 are supported, on the main frame 20, so as to project from the front side floor of the driver's seat 21. The tip part of each of the operation levers 22, 23 is gripped by the driver, and is used for indicating the rotation direction and rotation speed of the left wheel 12 and the right wheel 13. Each of the operation levers 22, 23 is approximately L-shaped, and has a gripping part 24 formed extending in the left-right direction on the upper end part. The gripping part 24 is gripped and operated by the driver. Each of the operation levers 22, 23 is capable of swinging, centered on an axis in position of the lower end part along the left-right direction.
The left wheel 12 and the right wheel 13 protrude more on the outer side than the left-right direction outer end of the side plate parts 20a, 20b of the main frame 20. The upper side of each of the wheels 12, 13 has at least one part covered by a wheel cover 25, and the left-right direction inner side end parts of the wheel covers 25 are fixed to the side plate parts 20a, 20b.
The two left and right caster wheels 15, 16 are steering control wheels supported on the front end part of the main frame 20, and are front wheels. The left wheel 12 and the right wheel 13 are independently travel-driven by a left hydraulic motor 30 (
As shown in
Each of the hydraulic pumps 32, 33 includes a left swash plate operation shaft 32b, which is a left adjustment shaft, and a right swash plate operation shaft 33b, which is a right adjustment shaft, for changing a tilting angle and orientation of a movable swash plate by rotation, and a swash plate operation lever 32c, 33c connected to the swash plate operation shaft 32b, 33b. The left swash plate operation shaft 32b adjusts a pressurized oil discharge amount of the left hydraulic pump 32. The right swash plate operation shaft 33b adjusts a pressurized oil discharge amount of the right hydraulic pump 33. The lower end parts of the operation levers 22, 23 of left and right corresponding sides are respectively connected, via a link 37, to the swash plate operation levers 32c, 33c. As a result, by having the operation levers 22, 23 swing in the front-rear direction, the swash plate operation shafts 32b, 33b will rotate. Also, the tilting angles and orientations of the movable swash plates of the hydraulic pumps 32, 33 will change. The discharge amounts of the hydraulic pumps 32, 33 change, in accordance with the change of tilting angles of the movable swash plates. By lowering the operation levers 22, 23 significantly to the front or the rear, the discharge amounts of the hydraulic pumps 32, 33 will increase. The left hydraulic motor 30 is driven by a pressurized oil supply from the left hydraulic pump 32. The right hydraulic motor 31 is driven by a pressurized oil supply from the right hydraulic pump 33. By lowering the operation levers 22, 23 more to the front than a neutral state, discharge directions will be prescribed so that the hydraulic pumps 32, 33 cause the hydraulic motors 30, 31 to rotate to one side. By having the operation levers 22, 23 fall more to the rear than a neutral state, discharge directions will be prescribed so that the hydraulic pumps 32, 33 cause the hydraulic motors 30, 31 to rotate to the other side. A neutral state is a state where there is no discharge of oil at a position the operation levers 22, 23 automatically return to in a state not gripped by the driver. For the rotation directions of the hydraulic motors 30, 31, one side corresponds to the rotation of a forward direction of the wheels 12, 13 and the other side corresponds to the rotation of a backward direction of the wheels 12, 13. Moreover, swing angle positions of the operation levers 22, 23 are detected by lever potentiometers 38, 39, which are swing angle detection sections. Detection signals of the lever potentiometers 38, 39 are transmitted to a controller 60 (
Moreover, in the hydraulic circuits 28, 29 of
The left and right wheels 12, 13 are respectively connected to the output shafts of the left and right hydraulic motors 30, 31, to be capable of transmitting power via the deceleration gear mechanisms 26b, 27b, which constitute the power generation units 26, 27. As will be described below, the vehicle 10 is capable of straight travel and turning travel by independent control of the left and right wheels 12, 13.
The engine 14 is arranged, in the vehicle 10, on the rear side of the driver's seat 21 (
By rotating the left and right wheels 12, 13 in mutually opposite directions at the same speed, such as described below, it will be possible for the vehicle 10 to rapidly turn around a turn center position 70 (
Moreover, as shown in
The solenoid is arranged surrounding the rod 46 on the inner side of the cylinder member 45, and operates so as to cause the rod 46 to project from the cylinder member 45 as a result of energizing the solenoid. The tip part of the rod 46 is joined to the other end part (the right end part of
Returning to
Moreover, both end parts in the left-right direction of the mower deck 19 respectively project to the outer side from both the left and right ends, in a front-rear direction middle part of the side plate parts 20a, 20b on both the left and right sides, which constitute the main frame 20. Moreover, the left and right wheels 12, 13 are respectively arranged more to the rear than the portion where the mower deck 19 projects to the outer side, and more on the outer side than the outer end in the left-right direction, on the side plate parts 20a, 20b of the main frame 20.
As shown in
As shown in
At the time when an obstacle target has been detected by at least one of the first sensors 50a, 50b, in the case where it is determined that the vehicle 10 is turning to the rear by the rear turn determination section 61, the turn stop section 62 causes the rear turn of the vehicle 10 to stop. At this time, by having the turn stop section 62 control the driving of the tension switching actuator 43, the driving of the left and right hydraulic motors 30, 31 is stopped by making the tension of the belt 36 zero, namely, by cutting the clutch. As a result, the left and right wheels 12, 13 stop, and therefore the turn to the rear stops. Moreover, at the time when an obstacle target has been detected by at least one of the first sensors 50a, 50b, in the case where it is determined that the vehicle 10 is stopped, the turn stop section 62 causes the stop of the turn to the rear of the vehicle 10 to be maintained. At this time, the stopping of straight travel to the rear may be maintained, along with maintaining a stop of a turn to the rear of the vehicle 10.
In addition, at the time when the lawnmower drive motor 48 is driving, at the time when an obstacle target has been detected by any one of the first sensors 50a, 50b, the lawnmower drive stop section 63 causes the driving of the lawnmower drive motor 48 to stop. At this time, the lawnmower drive stop section 63 causes rotation to stop by controlling the driving of the lawnmower drive motor 48. Moreover, at the time when the lawnmower drive motor 48 is drive-stopped, at the time when an obstacle target has been detected by any one of the first sensors 50a, 50b, the lawnmower drive stop section 63 causes the drive stop of the lawnmower drive motor 48 to be maintained.
Moreover, in order to release these stop and stop maintenance states, after a turn to the rear and the driving of the lawnmower 18 are stopped, or a stop maintenance is performed, for example, the driver causes the vehicle 10 to travel to the front or the like, and the obstacle targets will fall outside the detection regions of the first sensors 50a, 50b. Also, in this state, the controller 60 may be configured to perform a reset, for example, by returning the left and right operation levers 22, 23 to a neutral state. This reset causes the controller 60 to permit a turn to the rear of the vehicle, or driving of the lawnmower.
According to the above described vehicle 10, in a configuration where the left and right wheels 12, 13 are independently travel-driven by the hydraulic motors 30, 31, it will be easy to automatically detect an obstacle target that approaches the vehicle 10 in a relative manner at the time of turning travel to the rear. For example, the visual field of the driver riding in the driver's seat is the range shown by arrow Q in
Moreover, as shown by T3 in
Moreover, as shown in
While a case has been described, in
The controller 60 has the turn stop section 62 (
In addition, at the time when an obstacle target has been detected by at least one of the first sensors 50a, 50b and the second sensors 51a, 51b, the lawnmower drive stop section 63 causes the driving of the lawnmower drive motor 48 to stop, or causes a drive stop to be maintained.
According to the above described configuration, since the range in which it is possible to detect an obstacle target is extended, it will be easier to automatically detect an obstacle target that approaches the vehicle 10 at the time of turning travel to the rear. For example, even when obstacle targets T3 and T4 are positioned near the vehicle 10 at the rear of the vehicle 10, and these obstacle targets cannot be detected by the first sensors 50a, 50b, it will be easy to detect the obstacle targets T3 and T4 with the second sensors 51a, 51b. Configurations and actions other than these will be the same as the configurations of
Moreover, in the configurations of
Moreover, in the configuration of
Note that in the configuration of
While a case has been described, heretofore, where the controller 60 has both the turn stop section 62 and the lawnmower drive stop section 63, the controller may be configured to have only one of the turn stop section 62 and the lawnmower drive stop section 63. Moreover, reverse switches, which detect that the left and right operation levers 22, 23 are in a region indicating reversing, may be respectively provided, in the vehicle 10, near the left and right operation levers 22, 23. Detection signals of the reverse switches are transmitted to the controller 60. At this time, by using not only the lever potentiometers 38, 39, but also the detection signals of the reverse switches in an auxiliary manner, the controller 60 can more stably determine whether or not the vehicle 10 is turning to the rear.
Moreover, two left and right direction indication lights can be fixed at positions separated in the left-right direction on the front end part of the vehicle 10, such as at positions near a supporting part of the caster wheels 15, 16, for example, along with attaching direction indication switches to the left and right operation levers 22, 23. Each of the direction indication lights is constituted to be capable of flashing a light in the case were the direction indication switch of the side corresponding to the left or the right has been pressed. In such a configuration, since the vehicle 10 turning to the front or the rear side can be notified to a person nearby by the flashing of the direction indication lights, it becomes possible to perform safer travelling. Moreover, the direction indication lights may be used as the above described warning section. Specifically, when an obstacle target has been detected by one or both of the left and right first sensors 50a, 50b, the controller causes the left and right direction indication lights to turn on or flash at the same time.
Moreover, while a case has been described, heretofore, where a turn of the vehicle 10 is stopped by controlling the tension switching actuator 43, a turn of the vehicle 10 may be stopped by various methods other than this. For example, a throttle actuator that mechanically or electrically adjusts the opening of a throttle valve of the engine may be included, and a turn may be stopped by closing the throttle valve by having the controller 60 control the driving of the throttle actuator. Moreover, there may be a configuration that includes bypass valves 28a, 29a (
As shown in
In addition, in the case where only one wheel of the left and right wheels 12, 13 rotates to the rear, it is determined that the vehicle 10 is rapidly turning to the rear. Moreover, in the case where the left and right wheels 12, 13 rotate in opposite directions, and an absolute value of a ground movement speed of a rear rotating wheel, which is the wheel rotating to the rear, is larger than an absolute value of a ground movement speed of a front rotating wheel, which is the wheel rotating to the front, it is also determined that the vehicle 10 is rapidly turning to the rear. Such a rapid turn will be described afterwards using
When an obstacle target has been detected by at least one of the first sensors 50a, 50b, in the case where it is determined that the vehicle 10 is rapidly turning to the rear by the rear rapid turn determination section 61a, the turn stop section 62a causes the rapid turn to the rear of the vehicle 10 to stop. At this time, by having the turn stop section 62a control the driving of the tension switching actuator 43, the driving of the left and right hydraulic motors 30, 31 is stopped by making the tension of the belt 36 zero, namely, by cutting the clutch. As a result, the left and right wheels 12, 13 stop, and therefore the rapid turn to the rear stops. Moreover, when an obstacle target has been detected by at least one of the first sensors 50a, 50b, in the case where it is determined that the vehicle 10 is stopped, the turn stop section 62 causes the stop of a rapid turn to the rear of the vehicle 10 to be maintained. At this time, a straight travel stop to the rear may be maintained, along with maintaining a rapid turn stop to the rear of the vehicle 10.
Straight travel, turning travel, a pivot turn, and an ultra-pivot turn of the vehicle 10 are the same as the travelling or turning described using
Moreover, in order to release these stop and stop maintenance states, after a turn to the rear is stopped, or a stop maintenance is performed, for example, the driver causes the vehicle 10 to travel to the front or the like, and the obstacle targets will then fall outside the detection regions of the first sensors 50a, 50b. Also, in this state, the controller 60 may be configured to perform a reset, for example, by returning the left and right operation levers 22, 23 to a neutral state. This reset causes the controller 60 to permit a turn to the rear of the vehicle.
At the time when an obstacle target has been detected by at least one of the first sensors 50a, 50b, the controller 60 causes the warning light 73a to operate, along with causing a rapid turn to the rear of the vehicle 10 to stop, or causing a stop of a rapid turn to be maintained. As a result, the driver can recognize an approach to an obstacle target. Note that the warning buzzer 72a can be arranged near the driver's seat 21 of the vehicle, instead of the warning light 73a, or together with the warning light 73a. The warning buzzer 72a corresponds to a warning section. The operation of the warning buzzer 72a is controlled by the controller 60, and warns of an approach to an obstacle target using a sound. At the time when an obstacle target has been detected by one or both of the left and right first sensors 50a, 50b, the controller 60 causes the warning buzzer 72a to operate. The driver can recognize an approach to an obstacle target, by the operation of the warning buzzer 72a.
According to the above described vehicle 10, in a configuration where the left and right wheels 12, 13 are independently travel-driven by the hydraulic motors 30, 31, it will be easy to automatically avoid a collision with an obstacle target by the vehicle 10 at the time of rapid turning travel to the rear. In this case, different to the case where sensors capable of detecting the rear are arranged only on the rear end of the vehicle 10, similar to the configurations of
Moreover, when the vehicle 10 rapidly turns, using a zero-turn or the like, to the rear in the arrow a direction, as shown in
Moreover, in the case where the vehicle 10 turns rapidly using a pivot turn to the rear, as in
By referring to
According to the above described configuration, since the range capable of detecting an obstacle target is extended, it will be easier to automatically detect an obstacle target that approaches the vehicle 10 at the time of turning travel to the rear. For example, even when obstacle targets T3 and T4 (
Moreover, the vehicle 10 includes a throttle actuator 78 that mechanically or electrically adjusts the opening of a throttle valve of the engine 14. The throttle actuator 78 includes a motor (not illustrated) fixed to a rotating shaft (not illustrated) of the throttle valve. The controller 60 controls the motor of the throttle actuator 78, so that the engine 14 is driven at a constant rotation speed determined beforehand, by having a start switch (not illustrated) set to ON by a user. The controller 60 controls the throttle actuator 78 so as to cause the throttle valve to close, by having the start switch set to OFF by the user.
Moreover, when an obstacle target has been detected by at least one of the first sensors 50a, 50b, in the case where it is determined that the vehicle 10 is rapidly turning to the rear by the rear rapid turn determination section 61a (
The controller 60 drives the left and right swash plate operation levers 32c, 33c by controlling the driving of the left and right swash plate actuators 81, 82, in accordance with detection signals from the left and right lever potentiometers 38, 39. For example, in the case where the left and right operation levers 22, 23 have been lowered to the front, the controller 60 drives the swash plate operation levers 32c, 33c in one direction by controlling the swash plate actuators 81, 82, in accordance with detection signals from the lever potentiometers 38, 39. As a result, the discharge amounts of the left and right hydraulic pumps 32, 33 will change, and the movable swash plates of each of the hydraulic pumps 32, 33 will tilt, so that the discharge amounts of each of the hydraulic pumps 32, 33 increase at the advancing side. In the case where the left and right operation levers 22, 23 have been lowered to the rear, the controller 60 drives the swash plate operation levers 32c, 33c in the other direction by controlling the swash plate actuators 81, 82. As a result, the discharge amounts of the left and right hydraulic pumps 32, 33 will change, and the movable swash plates of each of the hydraulic pumps 32 and 33 will tilt, so that the discharge amounts of each of the hydraulic pumps 32, 33 increase in a direction of a rotation of the reversing side. Accordingly, the controller 60 causes the movable swash plates of the left and right hydraulic pumps 32, 33 to tilt, and causes the discharge amounts of the hydraulic pumps 32 and 33 to change, by controlling the driving of the left and right swash plate actuators 81, 82 in accordance with detection signals of the left and right lever potentiometers 38, 39.
In addition, the controller 60 sets the discharge amounts of each of the hydraulic pumps 32, 33 to substantially zero, by setting the tilting angles of the movable swash plates of the left and right hydraulic pumps 32, 33 to approximately a neutral state, by controlling the driving of the left and right swash plate actuators 81, 82. As a result, a rapid turn to the rear of the vehicle is stopped, or a stop of a rapid turn is maintained. Configurations and actions other than these will be the same as the configurations of
-
- Moreover, as shown in
FIG. 22A andFIG. 22B , the vehicle 10 includes the left reverse
switch 75 arranged in the surrounding part of the lower end part of the left operation lever 22, and the right reverse switch 76 arranged in the surrounding part of the lower end part of the right operation lever 23. The left and right reverse switches 75, 76 detect whether or not the left and right operation levers 22, 23 have been swung to regions (the R regions ofFIG. 22A andFIG. 22B ) indicating reversing, centered on shafts S in the left-right direction of the lower end part. Also, in the case where it is detected that the left and right operation levers 22, 23 have been swung to the regions for indicating reversing, the left and right reverse switches 75, 76 transmit these detection signals to the controller 60. For example, in the case where the front end parts of the reverse switches 75, 76 have been pressed downward, by the front end of the lower end parts of the operation levers 22, 23, it is detected that reversing has been instructing by the operation levers 22, 23 lowering from a neutral state to the rear. By using detection signals of the left and right lever potentiometers 38, 39, the controller 60 will determine whether or not the vehicle is rapidly turning to the rear. At this time, by having detection signals of the reverse switches 75, 76 used as assistance, it can be determined with stability whether or not the vehicle is rapidly turning to the rear.
- Moreover, as shown in
The left and right operation levers 22, 23 are capable of being displaced, from a maximum displacement position Fmax of a region indicating advancing to a maximum displacement position Rmax of a region indicating reversing, centered on the neutral position of
-
- Moreover, the vehicle 10 of
FIG. 21 ,FIG. 22A andFIG. 22B includes a throttle
actuator 78. The configuration of the throttle actuator 78 is the same as the configuration described usingFIG. 15 ,FIG. 16A andFIG. 16B . The throttle actuator 78 is controlled by the controller 60 (FIG. 21 ). When at least one of obstacle targets T1, T2, and T3 (FIG. 2 ) has been detected by the first sensors 50a, 50b, the controller 60 controls the driving of the throttle actuator 78. As a result, the controller 60 causes a turn of the vehicle 10 to decelerate by gradually bringing the throttle valve near to a closed state, and causes a turn to the rear to stop by closing the valve. Accordingly, it will become difficult for the vehicle 10 to collide with the obstacle target at the time of a turn.
- Moreover, the vehicle 10 of
Similar to the configuration shown in
Moreover, the vehicle 10 includes a left wheel rotation number sensor 142, which detects the number of rotations per unit time (for example, per minute) of the left wheel 12 in electromagnetism, and a right wheel rotation number sensor 143, which detects the number of rotations per unit time (for example, per minute) of the right wheel 13 in electromagnetism. The left and right wheel rotation number sensors 142, 143 correspond to left and right wheel rotation number detection sections. The controller 60 calculates the orientation of the vehicle in accordance with detection signals from the left and right wheel rotation number sensors 142, 143. For example, the controller 60 calculates a change in orientation of the vehicle with respect to a standard state, by calculating a change in the number of rotations of the left and right wheels 12, 13 from a standard state determined beforehand.
As shown in
In addition, in the case where only one wheel of the left and right wheels 12, 13 rotates to the rear, it is determined that the vehicle 10 is rapidly turning to the rear. Moreover, in the case where the left and right wheels 12, 13 rotate in opposite directions, and an absolute value of a ground movement speed of a rear rotating wheel, which is the wheel rotating to the rear, is larger than an absolute value of a ground movement speed of a front rotating wheel, which is the wheel rotating to the front, it is also determined that the vehicle 10 is rapidly turning to the rear. Such a rapid turn is as described using
When an obstacle target has been detected by at least one of the first sensors 50a, 50b, in the case where it is determined that the vehicle 10 is rapidly turning to the rear by the rear rapid turn determination section 61a, the turn deceleration stop section 62b causes the turn to the rear of the vehicle 10 to decelerate. Also, the turn deceleration stop section 62b causes the turn to stop prior to the vehicle colliding with the obstacle target. At this time, the turn deceleration stop section 62b causes the turn of the vehicle to decelerate by gradually bringing the throttle valve near to a closed state and causes the turn of the vehicle to the rear to stop by closing the valve, by controlling the driving of the throttle actuator 78.
It will be necessary for a turn stop of the vehicle to be performed prior to the vehicle colliding with the obstacle target. Accordingly, the controller 60 calculates a first orientation of the vehicle at the point in time when the obstacle target has been detected by the first sensors 50a, 50b, and a second orientation of the vehicle when the vehicle collides with the obstacle target. The first sensors 50a, 50b are capable of measuring a distance up to the obstacle target. Accordingly, the controller 60 can calculate the number of rotations of the left and right wheels 12, 13 until the obstacle target collides at the left-right direction side end of the vehicle, from a distance from the first sensor to the obstacle target at the time when the obstacle target begins to fall into the detection regions of the first sensors 50a, 50b at the time of a turn of the vehicle. At this time, for example, a rectangular parallelepiped vehicle simulation model including the vehicle 10 and simulating the vehicle 10 may be set, and a second orientation may be calculated at the time when the vehicle simulation model collides with an obstacle target. For example, the vehicle simulation model may be in contact with the outside of the vehicle, or may have a shape slightly larger than the vehicle. By setting such a vehicle simulation model, it will be easy to prevent an obstacle target colliding with the vehicle.
The second orientation may be calculated by assuming that the swing positions of the left and right operation levers 22, 23 are constant, from a point in time when an obstacle target has been detected by the first sensors 50a, 50b. Also, in the case where the actual swing positions of the left and right operation levers 22, 23 change after the first orientation, the second orientation may be corrected in accordance with this change.
Also, the controller 60 sets a third orientation prior to changing from the first orientation to the second orientation, and controls the rotation state of the left and right wheels 12, 13, so as to cause a turn to decelerate until the vehicle changes to the third orientation, and cause the turn to stop at the third orientation. At this time, the controller 60 can control the throttle actuator 78, and can cause the left and right wheels 12, 13 to stop in the third orientation, by closing the throttle valve.
Straight travel, turning travel, a pivot turn, and an ultra-pivot turn of the vehicle 10 are the same as the travelling or turning described using
By referring to
Moreover, in order to release this stop, after a turn to the rear is stopped, for example, the driver causes the vehicle 10 to travel to the front or the like, and the obstacle target will fall outside the detection regions of the first sensors 50a, 50b. Also, in this state, the controller 60 may be configured to perform a reset, for example, by returning the left and right operation levers 22, 23 to a neutral state. This reset is to make the controller 60 permit a turn to the rear of the vehicle.
Moreover, when an obstacle target has been detected by at least one of the first sensors 50a, 50b, the controller 60 causes the warning light 73a to operate, along with causing a rapid turn to the rear of the vehicle 10 to decelerate. As a result, the driver can recognize an approach to an obstacle target. Note that the warning buzzer 72a, which corresponds to a warning section, can be arranged near the driver's seat 21 of the vehicle, instead of the warning light 73a, or together with the warning light 73a. The operation of the warning buzzer 72a is controlled by the controller 60, and warns of an approach to an obstacle target using a sound. When an obstacle target has been detected by one or both of the left and right first sensors 50a, 50b, the controller 60 causes the warning buzzer 72a to operate. The driver can recognize an approach to an obstacle target, as a result of operation of the warning buzzer 72a.
According to the above described vehicle 10, in a configuration where the left and right wheels 12, 13 are independently travel-driven by the hydraulic motors 30, 31, it will be easy to automatically avoid a collision of the vehicle 10 with an obstacle target at the time of rapid turning travel to the rear. In this case, different to the case where sensors capable of detecting the rear are arranged only on the rear end of the vehicle 10, similar to the configurations of
Further, as shown by T3, referring to
In this way, when the left and right wheels 12, 13 rotate in opposite directions, and an absolute value of the ground movement speed of the wheel rotating to the rear is equal to or higher than an absolute value of the ground movement speed of the wheel rotating to the front, a rapid turn to the rear of the vehicle 10 will occur. Moreover, as shown in
According to the above described configuration, since the range in which detection of an obstacle target is possible is extended, it will be easier to automatically detect an obstacle target that approaches the vehicle 10 at the time of turning travel to the rear. For example, even at the time when obstacle targets T3 and T4 (
The controller 60 drives the left and right swash plate operation levers 32c, 33c by controlling the driving of the left and right swash plate actuators 81, 82, in accordance with detection signals from the left and right lever potentiometers 38, 39. For example, in the case where the left and right operation levers 22, 23 have lowered to the front, the controller 60 drives the swash plate operation levers 32c, 33c in one direction by the control of the swash plate actuators 81, 82, in accordance with detection signals from the lever potentiometers 38, 39. As a result, the discharge amounts of the left and right hydraulic pumps 32, 33 will change, and the movable swash plates of each of the hydraulic pumps 32, 33 will tilt, so that the discharge amounts of each of the hydraulic pumps 32, 33 increase at the advancing side. In the case where the left and right operation levers 22, 23 have lowered to the rear, the controller 60 drives the swash plate operation levers 32c, 33c in the other direction by control of the swash plate actuators 81, 82. As a result, the discharge amounts of the left and right hydraulic pumps 32, 33 will change, and the movable swash plates of each of the hydraulic pumps 32, 33 will tilt, so that the discharge amounts of each of the hydraulic pumps 32, 33 increase in a direction of a rotation of the reversing side. Accordingly, the controller 60 causes the movable swash plates of the left and right hydraulic pumps 32, 33 to tilt, and causes the discharge amounts of the hydraulic pumps 32, 33 to change, by controlling the driving of the left and right swash plate actuators 81, 82 in accordance with detection signals of the left and right lever potentiometers 38, 39.
In addition, the controller 60 brings the discharge amounts of each of the hydraulic pumps 32, 33 near to zero, by setting the tilting angles of the movable swash plates of the left and right hydraulic pumps 32, 33 to a neutral state, by controlling the driving of the left and right swash plate actuators 81, 82. As a result, a rapid turn to the rear of the vehicle decelerates. Also, the controller 60 sets the discharge amounts of each of the hydraulic pumps 32, 33 to substantially zero, by setting the tilting angles of the movable swash plates of the left and right hydraulic pumps 32, 33 to approximately a neutral state. As a result, a turn to the rear of the vehicle is stopped. Configurations and actions other than these will be the same as the configurations of
In addition, the turn deceleration stop section 62b (
Note that while illustration is omitted, the configurations in each example shown in
Moreover, the configurations in each of the above described examples can have two left and right direction indication lights fixed at positions separated in the left-right direction of the front end part of the vehicle 10, such as at positions near a supporting part of the caster wheels 15, 16, for example, along with attaching direction indication switches to the left and right operation levers 22, 23. Each of the direction indication lights is constituted to be capable of flashing a light in the case where the direction indication switch of the corresponding left or right side has been pressed. In such a configuration, since the vehicle 10 turning to the front or the rear side can be notified to a person in the surroundings by the flashing of the direction indication lights, it becomes possible to perform safer travelling. Moreover, the direction indication light may be used as the above described warning section. Specifically, when an obstacle target has been detected by one or both of the left and right first sensors 50a, 50b, the controller causes the left and right direction indication lights to turn on or flash at the same time.
The configuration of this example has the left and right operation levers 22, 23 of both left and right sides, in the configurations of
Moreover, the view, seen from the upper side of the vehicle, of a power transmission structure between power generation units for the left wheel and the right wheel, and an engine, is the same as that of
-
- By referring to
FIG. 19A andFIG. 19B , the two left and right swash plate actuators 81,
82 drive the swash plate operation levers 32c, 33c of the left and right corresponding sides, and the driving is controlled by the controller 60, which is a control device. The swash plate actuators 81, 82 include a piston cylinder mechanism, or a motor, for example, which rotates the swash plate operation levers 32c, 33c of the corresponding sides.
- By referring to
Moreover, the vehicle 10 includes the two left and right lever potentiometers 38, 39, which are swing angle detection sections. The left lever potentiometer 38 detects a swing angle position of the left operation lever 22, and the right lever potentiometer 39 detects a swing angle position of the right operation lever 23. Detection signals of each of the lever potentiometers 38, 39 are transmitted to the controller 60 (
The left and right operation levers 22, 23 are capable of being displaced, from a maximum displacement position Fmax of a region indicating advancing to a maximum displacement position Rmax of a region indicating reversing, centered on the neutral position of
Referring to
In addition, at the time a rapid turn has been performed, and it is determined to be an unstable turn, the controller 60 controls the driving of the left and right swash plate actuators 81, 82, as described below. As a result, the discharge amounts of each of the hydraulic pumps 32, 33 approach zero as a result of bringing the tilting angles of the movable swash plates of the left and right hydraulic pumps 32, 33 close to an approximately neutral state, and as a result this, the turning speed of the vehicle is reduced. Alternatively, the discharge amounts of each of the hydraulic pumps 32, 33 are substantially set to zero by setting the tilting angles of the movable swash plates of the left and right hydraulic pumps 32, 33 to an approximately neutral state, and as a result of this, the turning speed of the vehicle is suppressed. Specifically, the turning speed is reduced, or the turning speed is set to zero. In the case where the tilting angles of the movable swash plates are in an approximately neutral state, the movable swash plates will be in an approximately neutral position. At this time, the hydraulic motors 30, 31 will not be driven.
Moreover, by referring to
The charge oil path C1 is for replenishing oil from the oil reservoir E to the main oil path of a low pressure side, from among each of the main oil paths S1, S2, S3, and S4. Moreover, a bypass valve 28a is connected between both the first main oil path S1 and the second main oil path S2, and the oil reservoir E. A bypass valve 29a is connected between both the third main oil path S3 and the fourth main oil path S4, and the oil reservoir E. The bypass valves 28a, 29a are configured to be capable of switching between opening, which is a connection between the main oil paths S1, S2, S3, and S4 and the oil reservoir E, and closing, which is a disconnection, manually.
As shown in
In the case where such a detection value of the acceleration sensor 150 is excessively high, it can be determined to be an unstable turn where the front end part of the vehicle 10 is drastically turning to the left or right. Detection signals of the acceleration sensor 150 are transmitted to the controller 60 (
As shown in
For example, in the case where only one wheel of the left and right wheels 12, 13 rotates, it is determined that the vehicle 10 is rapidly turning, which is called a pivot turn, which is a turn centered on the ground position of the one wheel of the left and right wheels 12, 13. Moreover, in the case where the left and right wheels 12, 13 rotate in opposite directions, it is determined that the vehicle 10 is rapidly turning with a reduced turning radius. In particular, in the case where the left and right wheels 12, 13 rotate in opposite directions, and the absolute values of the rotation speeds of the left and right wheels 12, 13 are the same, it is determined that the vehicle 10 is turning rapidly, which is called a zero-turn or an ultra-pivot turn, which is a turn centered on the center between the left and right wheels 12, 13. As a result, it can be detected that the vehicle is turning rapidly. Such a rapid turn is as described using
When the detection value of the acceleration sensor 150 is equal to or higher than a threshold determined beforehand for the acceleration, the unstable turn determination section 60b determines that it is an unstable turn. The swash plate actuator control section 60d causes the movable swash plate of the left hydraulic pump 32 to tilt by controlling the driving of the left swash plate actuator 81 in accordance with a detection signal of the left lever potentiometer 38. Moreover, the swash plate actuator control section 60d causes the movable swash plate of the right hydraulic pump 33 to tilt by controlling the driving of the right swash plate actuator 82 in accordance with a detection signal of the right lever potentiometer 39.
In addition, when a rapid turn has been performed, and it is determined to be an unstable turn, the turning speed suppression section 60c reduces the turning speed, in the vehicle 10, in accordance with a determination result of the rapid turn determination section 60a and the unstable turn determination section 60b. Specifically, the turning speed suppression section 60c brings the tilting angles of the swash plates of the left hydraulic pump 32 and the right hydraulic pump 33 to a neutral state by controlling the driving of the left swash plate actuator 81 and the right swash plate actuator 82. As a result, the turning speed of the vehicle 10 is reduced, by bringing the discharge amounts of the left hydraulic pump 32 and the right hydraulic pump 33 close to zero. Moreover, the turning speed suppression section 60c may set the turning speed to zero by setting the discharge amounts of the left hydraulic pump 32 and the right hydraulic pump 33 to substantially zero, by setting the tilting angles of the swash plates of the left hydraulic pump 32 and the right hydraulic pump 33 to an approximately neutral state. As a result, the vehicle is stopped. While the portions that execute each of the functions of the rapid turn determination section 60a, the unstable turn determination section 60b or the like of the controller 60 may be integrated into one controller, multiple controllers may be connected by cables, and multiple functions may be separately executed by the multiple controllers.
Straight travel, turning travel, a pivot turn, and an ultra-pivot turn of the vehicle 10 are the same as the travelling or turning described by using
According to the above described vehicle 10, in a configuration where the left and right wheels 12, 13 are independently travel-driven by the left and right hydraulic motors 30, 31, an unstable turn can be automatically suppressed. For example, at the time when the turning speed is low, in the case where the vehicle turns rapidly using a zero-turn such as in
Moreover, the front end part of the vehicle 10 will move significantly in the left-right direction, in a rapid turn where the turning center is positioned between the ground positions of the left and right wheels 12, 13, or the ground position of one wheel of the left and right wheels 12, 13. As a result, in the case where the acceleration sensor 150 is arranged on the front end part of the vehicle 10, such as in an embodiment, the detection accuracy of turning stability will improve. Note that the arrangement position of the acceleration sensor 150 is not limited to the configuration of being arranged on the front end part of the vehicle 10, and can be arranged at various positions, as long as it is arranged on a member with high rigidity in the vehicle 10. For example, the acceleration sensor 150 may be arranged near the center of gravity of the vehicle 10. Moreover, in the case where the front wheels are driving wheels, and the rear wheels are caster wheels, the rear end part of the vehicle will move significantly in the left-right direction, and therefore the detection accuracy of turning stability can be improved, by arranging the acceleration sensor on the rear end part of the vehicle.
Moreover, a case has been described, heretofore, where the acceleration sensor 150 is used as a turning stability relationship sensor that detects a turning stability amount related to turning stability. On the other hand, an angular velocity sensor 151 (
When a rapid turn has been performed, and a detection value of the angular velocity sensor 151 is equal to or higher than a threshold, the turning speed suppression section 60c of the controller 60 reduces the turning speed, by decelerating or stopping the vehicle by the operation of the swash plate actuators 81, 82. In the case of such a configuration, an unstable turn can also be automatically suppressed similar to the case of using the acceleration sensor 150. For example, when the turning speed is low, in the case where the vehicle turns rapidly, the angular velocity detected by the angular velocity sensor 151 will be less than a threshold, and therefore the rapid turn will not be suppressed. On the other hand, at the time when the turning speed is excessively high, in the case where the vehicle turns rapidly, the angular velocity detected by the angular velocity sensor 151 will be equal to or higher than a threshold, and therefore the rapid turn will be suppressed. As a result, unstable turning can be automatically suppressed. Configurations and actions other than these will be the same as the configurations of
Moreover, referring to
In addition, when a rapid turn has been performed, and a detection value of the acceleration sensor 150 or the angular velocity sensor 151 is equal to or higher than a threshold, the turning speed suppression section 60c (refer to
Another example of an embodiment will be described, by referring to
Moreover, the vehicle 10 includes a throttle actuator 78 that mechanically or electrically adjusts the opening of the throttle valve of the engine 14. The controller 60 (refer to
Moreover, when a rapid turn has been performed, and a detection value of the acceleration sensor 150 (
Moreover, the third pressure sensor 183 detects the pressure of the third main oil path S3 connecting one port P3 of the right hydraulic pump 33 and one port Q3 of the right hydraulic motor 31. In addition, the fourth pressure sensor 184 detects the pressure of the fourth main oil path S4 connecting the other port P4 of the right hydraulic pump 33 and the other port Q4 of the right hydraulic motor 31. Detection signals of each of the pressure sensors 181, 182, 183, 184 are transmitted to the controller 60 (
For example, the region of the shaded part U1 of
Moreover, the region of the shaded part U3 of
For example, combining the two conditions shown by arrow J1 means pressure of the first main oil path S1 increasing and the left operation lever 22 being operated significantly to the front, and additionally the pressure of the fourth main oil path S4 increasing and the right operation lever 23 being operated significantly to the rear. In the case where this combination is established, the vehicle 10 will turn rapidly in the state of a zero-turn or near to a zero-turn to the left side, and will have a high speed. At this time, by determining that a rapid turn has been performed, and that it is an unstable turn, the controller 60 (
On the other hand, combining the two conditions shown by arrow J2 means the pressure of the second main oil path S2 increasing and the left operation lever 22 being operated significantly to the rear, and additionally the pressure of the third main oil path S3 increasing and the right operation lever 23 being operated significantly to the front. In the case where this combination is established, the vehicle will turn rapidly in the state of a zero-turn or near to a zero-turn to the right side, and will have a high speed. At this time, by determining that a rapid turn has been performed, and that it is an unstable turn, the controller will reduce the turning speed by the swash plate actuators. Configurations and actions other than these will be the same as the configurations of
Note that while a case has been described, in each of the above described embodiments, where the riding type vehicle is a riding lawnmower vehicle that includes a lawnmower, the present invention is not limited to such a configuration, and the riding type vehicle may be a vehicle that does not include a lawnmower. For example, each of the above described embodiments may be a vehicle capable of travelling on uneven ground or a road, by omitting the lawnmower. A forklift, wheelchair or the like driven by left and right electric motors can be included, as specific examples.
At least one riding type vehicle of each of the above described embodiments has the configuration of the above described first riding type vehicle. Accordingly, in a configuration where the left and right wheels are capable of being independently driven, with regard to a rotation direction and a rotation speed, it will be easy to automatically detect an obstacle target that approaches the vehicle at the time of turning travel to the rear. In particular, since each of the two first sensors are arranged on both the left and right sides, more to the front than the rear end of the vehicle, and are configured to detect an obstacle target positioned on the rear side, different to the case where sensors capable of detecting the rear are arranged on the rear end of the vehicle, it will be easy to detect an obstacle target positioned more on the outer side than both left and right ends of the vehicle and more to the front than the rear end of the vehicle.
At least one riding type vehicle of each of the above described embodiments has the configuration of the above described second riding type vehicle or third riding type vehicle. Accordingly in a configuration where the left and right wheels are capable of being independently driven, with regard to a rotation direction and a rotation speed, it will be easy to automatically avoid a collision with an obstacle target at the time of a rapid turn to the rear.
At least one riding type vehicle of each of the above described embodiments has the configuration of the above described fourth riding type vehicle. Accordingly, in a configuration where the left and right wheels are capable of being independently driven, with regard to a rotation direction and a rotation speed, an unstable turn can be automatically suppressed.
Claims
1. A riding type vehicle having
- a driving source,
- a left wheel and a right wheel,
- a transmission configured to receive power from the driving source to independently operate and drive the left wheel and the right wheel with regard to a rotation direction and a rotation speed, and
- caster wheels separately provided in a front-rear direction with respect to the left wheel and the right wheel, the riding type vehicle comprising:
- two first sensors arranged on both left and right sides more to a front side than a rear end of the vehicle, the two first sensors configured to detect an obstacle target located on a rear side, the obstacle target being a target becoming an obstacle at the time of reversing or turning.
2. The riding type vehicle according to claim 1, wherein
- the vehicle has a lawnmower, and both left-right direction end parts of a mower deck covering an upper side of a blade of the lawnmower respectively project to an outer side from left and right ends of a longitudinal direction middle part of a vehicle body, and
- the two first sensors are arranged separated on left and right end parts protruding from the vehicle body, on an upper side of the mower deck.
3. The riding type vehicle according to claim 2, wherein
- the left wheel and the right wheel are respectively arranged more to a rear side than a portion where the mower deck protrudes to an outer side and more on an outer side than left-right direction outer ends, and are covered on at least a part of an upper side by wheel covers, in the vehicle body, and
- the riding type vehicle further comprises two second sensors arranged on upper side portions on the left and right wheel covers, the two second sensors configured to detect the obstacle target located on a rear side.
4. The riding type vehicle according to claim 1, further comprising:
- a control device for causing a turn to the rear to stop, or causing a turn stop to be maintained, at the time when the obstacle target has been detected by the first sensors.
5. The riding type vehicle according to claim 1, wherein
- the vehicle has a lawnmower, and further comprises a control device for causing driving of the lawnmower to stop, or causing a drive stop to be maintained, at the time when the obstacle target has been detected by the first sensors.
6. The riding type vehicle according to claim 1, further comprising:
- a warning section for warning of an approach to the obstacle target; and
- a control device for causing the warning section to operate at the time when the obstacle target has been detected by the first sensors.
7. A riding type vehicle having
- a driving source,
- a left wheel and a right wheel,
- a transmission configured to receive power from the driving source to independently operate and drive the left wheel and the right wheel with regard to a rotation direction and a rotation speed, and
- caster wheels separately provided in a front-rear direction with respect to the left wheel and the right wheel, wherein
- the riding type vehicle is capable of a rapid turn where only one of the left wheel and the right wheel rotates around a turn center position, or the left wheel and the right wheel rotate in opposite directions, the riding type vehicle comprising:
- a sensor, arranged on the vehicle, capable of detecting an obstacle target on a rear side, the obstacle target being a target becoming an obstacle at the time of reversing or turning; and
- a control device for causing a rapid turn to the rear to stop, or causing a stop of a rapid turn to be maintained, at the time when the obstacle target has been detected by the sensor.
8. The riding type vehicle according to claim 7, further comprising:
- a warning section for warning of an approach to the obstacle target, wherein
- the control device causes the warning section to operate, along with causing a rapid turn to the rear to stop, or causing a stop of a rapid turn to be maintained, at the time when the obstacle target has been detected by the sensor.
9. The riding type vehicle according to claim 7, further comprising:
- a clutch arranged between an output section of the driving source and an input section of the transmission; and
- a switching mechanism including a switching actuator for engaging/disengaging power transmission through the clutch, wherein
- the control device causes a rapid turn to the rear to stop, or causes a stop of a rapid turn to be maintained, by cutting power transmission through the clutch by controlling driving of the switching actuator.
10. The riding type vehicle according to claim 7, wherein
- the driving source is an engine, and the riding type vehicle further comprises a throttle actuator for adjusting an opening of a throttle valve of the engine, and
- the control device causes a rapid turn to the rear to stop, or causes a stop of a rapid turn to be maintained, by closing the throttle valve by controlling driving of the throttle actuator.
11. The riding type vehicle according to claim 7, wherein
- the transmission includes
- a left hydraulic motor driven by a pressurized oil supply from a left hydraulic pump, and a right hydraulic motor driven by a pressurized oil supply from a right hydraulic pump,
- a left main oil path connecting the left hydraulic motor and the left hydraulic pump, and a left bypass valve connected between the left main oil path and an oil reservoir,
- a left bypass actuator for switching a closing and opening of the left bypass valve,
- a right main oil path connecting the right hydraulic motor and the right hydraulic pump, and a right bypass valve connected between the right main oil path and an oil reservoir, and
- a right bypass actuator for switching a closing and opening of the right bypass valve, and
- the control device causes a rapid turn to the rear to stop, or causes a stop of a rapid turn to be maintained, by setting the left bypass valve and the right bypass valve to an opened state at a same time by controlling driving of the left bypass actuator and the right bypass actuator.
12. The riding type vehicle according to claim 7, wherein
- the transmission includes
- a left hydraulic motor driven by a pressurized oil supply from a variable-capacity swash-plate type left hydraulic pump, and a right hydraulic motor driven by a pressurized oil supply from a variable-capacity swash-plate type right hydraulic pump,
- a left adjustment shaft for adjusting a hydraulic discharge amount of the left hydraulic pump,
- a right adjustment shaft for adjusting a hydraulic discharge amount of the right hydraulic pump,
- a left swing angle detection section for detecting a swing angle position of a left operation lever,
- a right swing angle detection section for detecting a swing angle position of a right operation lever,
- a left actuator, for driving a left swash plate operation lever, connected to the left adjustment shaft, and
- a right actuator, for driving a right swash plate operation lever, connected to the right adjustment shaft, and
- the control device causes the discharge amount of the left hydraulic pump to change by controlling driving of the left actuator in accordance with a detection signal of the left swing angle detection section, causes the discharge amount of the right hydraulic pump to change by controlling driving of the right actuator in accordance with a detection signal of the right swing angle detection section, and causes a rapid turn to the rear to stop, or causes a stop of a rapid turn to be maintained, by setting the discharge amounts of the left hydraulic pump and the right hydraulic pump to substantially zero by controlling driving of the left actuator and the right actuator.
13. A riding type vehicle having
- a driving source,
- a left wheel and a right wheel,
- a transmission configured to receive power from the driving source to independently operate and drive the left wheel and the right wheel with regard to a rotation direction and a rotation speed, and
- caster wheels separately provided in a front-rear direction with respect to the left wheel and the right wheel, wherein
- the riding type vehicle is capable of a rapid turn where only one of the left wheel and the right wheel rotates around a turn center position, or the left wheel and the right wheel rotate in opposite directions, the riding type vehicle comprising:
- a sensor, arranged on the vehicle, capable of detecting an obstacle target on a rear side, the obstacle target being a target becoming an obstacle at the time of reversing or turning; and
- a control device for causing a turn to decelerate, at the time when the obstacle target has been detected by the sensor and a rapid turn is performed to the rear, and causing a turn to stop prior to the vehicle colliding with the obstacle target.
14. The riding type vehicle according to claim 13, further comprising:
- a left wheel rotation number detection section for detecting a number of rotations per unit time of the left wheel; and
- a right wheel rotation number detection section for detecting a number of rotations per unit time of the right wheel, wherein
- the control device calculates an orientation of the vehicle in accordance with detection signals from the left and right wheel rotation number detection sections, calculates a first orientation of the vehicle at the time when the obstacle target has been detected by the sensor, and a second orientation of the vehicle, or a rectangular parallelepiped vehicle simulation model including the vehicle, at the time when the vehicle or the vehicle simulation model collides with the obstacle target, and controls rotation states of the left wheel and the right wheel so as to cause a turn to decelerate from the first orientation until changing to a third orientation prior to the second orientation, and cause the turn to stop at the third orientation.
15. The riding type vehicle according to claim 13, further comprising:
- a warning section for warning of an approach to the obstacle target, wherein
- the control device causes the warning section to operate, along with causing a turn to decelerate, at the time when the obstacle target has been detected by the sensor and a rapid turn is performed.
16. The riding type vehicle according to claim 13, wherein
- the driving source is an engine, and the riding type vehicle further comprises a throttle actuator for adjusting an opening of a throttle valve of the engine, and
- the control device causes a turn to decelerate by gradually bringing the throttle valve near to a closed state and causing a turn to the rear to stop by closing the valve, by controlling driving of the throttle actuator.
17. The riding type vehicle according to claim 13, wherein
- the transmission includes
- a left hydraulic motor driven by a pressurized oil supply from a variable-capacity swash-plate type left hydraulic pump, and a right hydraulic motor driven by a pressurized oil supply from a variable-capacity swash-plate type right hydraulic pump,
- a left adjustment shaft for adjusting a hydraulic discharge amount of the left hydraulic pump,
- a right adjustment shaft for adjusting a hydraulic discharge amount of the right hydraulic pump,
- a left swing angle detection section for detecting a swing angle position of a left operation lever,
- a right swing angle detection section for detecting a swing angle position of a right operation lever,
- a left actuator, for driving a left swash plate operation lever, connected to the left adjustment shaft,
- a right actuator, for driving a right swash plate operation lever, connected to the right adjustment shaft, and
- the control device causes the discharge amount of the left hydraulic pump to change by controlling driving of the left actuator in accordance with a detection signal of the left swing angle detection section, and causes the discharge amount of the right hydraulic pump to change by controlling driving of the right actuator in accordance with a detection signal of the right swing angle detection section, causes a turn to decelerate by bringing the discharge amounts of the left hydraulic pump and the right hydraulic pump near to zero and causes a turn to the rear to stop by setting to substantially zero, by controlling driving of the left actuator and the right actuator.
18. The riding type vehicle according to claim 13, further comprising:
- a clutch arranged between an output section of the driving source and an input section of the transmission; and
- a switching mechanism including a switching actuator for engaging/disengaging power transmission through the clutch, wherein
- the control device causes a turn to decelerate by setting power transmission through the clutch to a half-transmission state and causes a turn to the rear to stop by cutting power transmission through the clutch, by controlling driving of the switching actuator.
19.-28. (canceled)
Type: Application
Filed: Mar 23, 2020
Publication Date: Sep 17, 2020
Inventors: Ryoichi KAWAI (Amagasaki), Hirohiko KAWADA (Amagasaki), Seishi KOSEGAWA (Amagasaki), Koga YAMANE (Amagasaki), Etsuo MIYAKE (Amagasaki), Masaki WATANABE (Amagasaki), Koji SAKATA (Amagasaki), Kenji SHIBA (Amagasaki), Kosuke ONODA (Amagasaki), Hiroki MAEHARA (Amagasaki)
Application Number: 16/826,663