JPH06185379A - Engine emergency stop device for automatic traveling working vehicle - Google Patents

Abstract

PURPOSE:To automatically stop the traveling of an automatic traveling working vehicle, when an abnormality is caused in the operation of the speed-change gear in the working vehicle. CONSTITUTION:An automatic traveling working vehicle that is automatically traveled by remote operation is provided with a speed-change gear operation actuator 21 for operating the speed-change gear of a transmission 5, a detecting means (not shown) for detecting the driving current of this actuator 21, a judging means (not shown) for judging whether or not the driving current detected by this judging means is abnormal, and a stopping means by which an engine 14 is stopped when the judging means judges that the driving current is abnormal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine emergency stop for an automatic traveling work vehicle, which is designed to automatically stop the engine when an abnormality occurs in the shift position operation of the automatic traveling work vehicle. Regarding the device.

[0002]

2. Description of the Related Art A conventional automatic work vehicle is provided with an engine emergency stop device for stopping the traveling by stopping the engine when an abnormality occurs in the shift position operation. Fair 4-1339
There is one disclosed in Japanese Patent No. 4 publication.

In the conventional engine emergency stop device disclosed in Japanese Utility Model Publication No. 4-13394, a potentiometer for detecting the gear shift position is arranged so that the target gear shift position of the continuously variable transmission coincides with the actual gear shift position. In general, feedback control of the operation of an actuator such as a motor that performs a gear shift operation is performed based on gear shift position detection information from sensors such as.

Then, the elapsed time until the deviation between the shift target value and the detected value from the sensor falls within a fixed judgment value is monitored. If the deviation does not fall within the fixed judgment value within this elapsed time, the shift is performed. The engine is stopped when it is judged that an abnormality has occurred in the position operation.

[0005]

Therefore, even if an abnormality occurs in the shift position operation, the engine cannot be stopped until the preset elapsed time has elapsed.

Further, when the sensor malfunctions and the detected value output from the sensor accidentally substantially matches the shift target value, it is determined that the engine is in a normal state and the engine is not stopped.

[0007]

The invention according to claim 1 is
In an automated driving vehicle that automatically travels by remote control,
A shift position operating actuator for operating the shift position of the transmission, a detecting means for detecting a drive current of the shift position operating actuator, and a judgment for determining whether or not the drive current detected by the detecting means is abnormal. Means and a stopping means for stopping the engine when the judging means judges that there is an abnormality are provided.

According to a second aspect of the present invention, in the first aspect of the present invention, an engine stopping actuator for stopping the engine when the power supply is cut off is provided, and the engine stopping actuator is provided between the engine stopping actuator and a power source. The fuse for preventing overcurrent and the fuse for preventing overcurrent provided between the actuator for gear shift position operation and the power source are shared.

[0009]

According to the present invention, the drive current flowing through the shift position operating actuator is detected by the detection means, and when the determination means determines that the drive current detected by the detection means is abnormal, The engine is stopped by the stopping means and the traveling of the automatic work vehicle is stopped. Therefore, it is possible to quickly detect an abnormality that has occurred in the gear shift position operating actuator and the like, and to prevent the automatic traveling work vehicle from continuing traveling while the gear shift position operating actuator and the like have an abnormality.

According to the second aspect of the present invention, the engine is stopped when the fuse provided between the gear shift position operating actuator and the power source is blown because an overcurrent flows through the gear shift position operating actuator. Energization to the engine stopping actuator is cut off and the engine is stopped without making a control determination or the like.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. The remote-controlled lawn mower 1 which is an automatic traveling work vehicle is provided with a pair of left and right front wheels 2 which are steering wheels and driving wheels and a pair of left and right rear wheels 3 which are driving wheels. A mower 4 is mounted between the front wheel 2 and the rear wheel 3 so as to be movable up and down. Further, the remote-controlled lawn mower 1 is provided with an HST (hydraulic continuously variable transmission) 5 which is a transmission and a steering drive device 6, and further controls the HST 5 and the steering drive device 6. A control unit 7 which is a control unit for performing the operation is provided.

The left and right front wheels 2 are connected by a pair of knuckle arms 8 and 9 forming an Ackermann mechanism and a tie rod 10, and the knuckle arms 8 and 9 are rotatably supported around a support shaft 11 in a substantially horizontal plane. Has been done. One of the knuckle arms 8 is formed with a protrusion 12 extending rearward, and the steering drive device 6 is connected to the protrusion 12. A steering sensor 13 that detects the steering angle of the front wheels 2 is provided on the support shaft 11 that supports one knuckle arm 8. The steering sensor 13 is connected to the control unit 7.

Next, an engine 14 is connected to the HST 5, which is connected to the front wheel 2 via transmission shafts 15 and 16 and to the rear wheel 3 via a transmission shaft 17. ing. Further, the HST 5 is provided with a speed change arm 19 which is rotatable around the support shaft 18 and which changes the speed of the HST 5 by rotating the speed change arm 19, and the speed change arm 19 is provided at the tip of the speed change arm 19. The variable speed drive device 20 for rotating is connected.
The speed change drive device 20 is formed by a motor 21 which is an actuator for operating a speed change position, and a worm gear 22 connected to a motor shaft of the motor 21, and the support shaft 18 rotates the speed change arm 19. A shift position sensor 23 is provided for detecting the shift position of the HST 5 by detecting the moving position, and the shift position sensor 23 is connected to the control unit 7.

The motor 21 is connected to a battery 24 which is a power source. Between the motor 21 and the battery 24, an overcurrent preventing fuse 25 and a current supply direction to the motor 21 are provided. Reversed relay 2
6, 27 are interposed. Here, the battery 2
4 and the control unit 7 are connected by a conductor 30 having a key switch 28 and a fuse 29,
One ends of the coils of the relays 26 and 27 are connected to the lead wire 30, and the other ends of these coils are connected to the control unit 7. In addition, the relays 26, 27
Is connected to the battery 24 via the fuse 25, and contacts b of the relays 26 and 27 are connected to the resistor 31 for detecting the drive current flowing through the motor 21.
Is connected to ground via. In addition, relay 2
One end of a lead wire 32 is connected to the lead wire connecting the b-contacts 6 and 27 and the resistance 31, and the other end of the lead wire 32 is connected to the control unit 7 and the motor 21 is installed in the control unit 7. Detection means (not shown) for detecting the flowing drive current is provided.

Next, the engine 14 is equipped with a key stop solenoid 33 that enables the engine 14 to operate by being energized and stops the engine 14 by cutting off the energization. A relay 34 for connecting and disconnecting power to the top solenoid 33 is provided. One end of the coil of the relay 34 is connected to the battery 24 via the fuse 29 and the key switch 28, and the other end of the coil is connected to the control unit 7. Further, the contact a of the relay 34 is connected to the battery 24 via the fuse 25, and the contact b of the relay 34 is connected to the key stop solenoid 33.

Here, in the control unit 7, a judging means (not shown) for judging whether the drive current flowing through the motor 21 detected by the detecting means is abnormal, and this judging means is abnormal. If it is determined that the engine 14 is turned off, the power supply to the key stop solenoid 33 is cut off.
And a stopping means (not shown) for stopping the operation.

Next, a remote controller 35 for remotely controlling the remote-controlled lawn mower 1 is provided, and an antenna 3 for receiving a control signal from the remote controller 35.
6 is provided in the remote-controlled lawn mower 1, and the received control signal is input to the control unit 7. In addition,
The remote controller 35 includes a steering setting section 37 for instructing a steering direction and a steering amount, a traveling setting section 38 for instructing a traveling speed (speed and forward / backward traveling direction), and a start switch for the engine 14. 39, a stop switch 40, an operating portion (not shown) for the mower 4 and the like are provided.

In such a structure, first, a procedure for starting the remote-controlled lawn mower 1 will be described. When the key switch 28 is turned “on”, the battery 24 is connected to the relay 3
The coil No. 4 is energized, and the a contact and the b contact of the relay 34 are connected. Then, by connecting the a-contact and the b-contact of the relay 34, the key stop solenoid 33 is energized, and the engine 14 is ready to start. Therefore, when the start switch 39 of the remote controller 35 is turned "on" from this state, the control unit 7 controls the start of the engine 14 based on the control signal from the remote controller 35, and the engine 14 is started.

After the engine 14 is started, the steering drive unit 6 is driven by the control of the control unit 7 by operating the steering setting section 37,
Steering control of the remote-controlled lawn mower 1 is performed. Further, by operating the travel setting unit 38, the variable speed drive device 20 is driven through the control by the control unit 7, and the travel control of the remote-controlled lawn mower 1 is performed.

Here, at the time of traveling control, the speed change drive device 20
The motor 21 is driven, but the drive current flowing through the motor 21 is constantly detected by the detection means provided in the control unit 7, and it is determined whether or not the drive current detected by this detection means is abnormal. It is judged by the judgment means provided inside. When the drive current flowing through the motor 21 is within the set range, it is determined that the drive current is normal and the operating state of the motor 21 is normal, and steering control and travel control are continuously performed.

On the other hand, if an abnormality occurs in the motor 21,
For example, when the gear shift operation cannot be smoothly performed due to the action of overload, the drive current flowing through the motor 21 increases, and when the drive current is out of the set range, the drive current is determined by the determination means. Is judged to be abnormal. When the determination means determines that the drive current flowing through the motor 21 is abnormal, the stop means provided in the control unit 7 is activated to cut off the power supply to the coil of the relay 34. When the power supply to the coil of the relay 34 is cut off, the connection between the a contact and the b contact of the relay 34 is cut off, and the power supply to the key stop solenoid 33 is cut off, so that the engine 14 is automatically stopped. .

Therefore, the remote-controlled lawnmower 1 does not continue to run in a state where the gear shifting operation cannot be performed smoothly due to the effect of overload on the motor 21, and the remote-controlled lawnmower 1 cannot be remotely controlled or is remotely controlled. It is possible to prevent poor control.

When an abnormality occurs in the motor 21 and the drive current flowing through the motor 21 increases, and when an abnormality occurs in the control unit 7, the engine 14 can be stopped by the stop means. It may be impossible. However, when the drive current flowing through the motor 21 exceeds a certain value, the fuse 25 is broken, and this fuse 25 is shared as a fuse for preventing overcurrent provided between the key stop solenoid 33 and the battery 24. Therefore, an overcurrent flows through the motor 21 and the fuse 2
When the wire 5 is disconnected, the power supply to the key stop solenoid 33 is cut off and the engine 14 is automatically stopped.

Therefore, when the fuse 25 is blown due to the occurrence of an abnormality in the motor 21 and the flow of an overcurrent, what is the abnormality occurring in the motor 21 and the engine 14 is stopped. The engine 14 is instantaneously stopped without making a control judgment as to whether or not the remote-controlled lawnmower 1 is prevented from traveling in a state where remote-control is impossible.

[0025]

As described above, according to the invention described in claim 1, in an automatic traveling work vehicle that automatically travels by remote control, a shift position operating actuator for operating a shift position of a transmission, and this shift position operating actuator. Detecting means for detecting the drive current, determining means for determining whether the drive current detected by the detecting means is abnormal, and stopping means for stopping the engine when the determining means determines abnormal When an abnormality such as an overload action occurs in the gear shift position operating actuator, the drive current flowing through the gear shift position operating actuator becomes large, and the drive current detected by the detecting means becomes the judging means. If it is determined to be abnormal by the stop means, the engine can be stopped by the stopping means and the traveling of the automatic work vehicle can be stopped. Therefore, it is possible to quickly detect an abnormality that has occurred in the shift position operating actuator, and prevent the occurrence of a situation in which the traveling of the automatic traveling work vehicle is continued in the state where the traveling control is impossible or poor. It has the effect of being able to.

As described above, the invention according to claim 2 is the invention according to claim 1, which further comprises an engine stopping actuator for stopping the engine when the energization is interrupted, and the engine stopping actuator and the power source are connected to each other. Since the fuse for preventing overcurrent provided between and the fuse for preventing overcurrent provided between the shift position operating actuator and the power source are shared, an overcurrent flows to the shift position operating actuator. If the fuse provided between the power supply and the power source is blown, the engine stop actuator is de-energized at the same time and the engine can be stopped to stop the traveling of the automatic work vehicle. Whether to stop the engine when an overcurrent flows through the position operation actuator and the fuse provided between the actuator and the power supply is blown It is possible to stop the running of the automated work vehicle by stopping the engine instantaneously without making the control judgment of the above, and reliably prevent the situation where the automated work vehicle is run in a state where the running control is impossible. It has the effect of being able to do so.

[Brief description of drawings]

FIG. 1 is a block diagram showing a travel control and engine emergency stop system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a system for traveling control and steering control.

FIG. 3 is a side view showing the overall structure of a remote-controlled lawn mower adopting the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Automatic work vehicle 5 Transmission 14 Engine 21 Shift position operation actuator 24 Power supply 25 Fuse 33 Engine stop actuator

Claims (2)

[Claims] 1. In an automatic traveling work vehicle that automatically travels by remote control, a shift position operating actuator for operating a shift position of a transmission, a detecting means for detecting a drive current of the shift position operating actuator, and this detection. Automatic traveling work characterized in that it is provided with a judging means for judging whether or not the drive current detected by the means is abnormal, and a stopping means for stopping the engine when the judging means judges that the driving current is abnormal. Car engine emergency stop device. 2. An engine stopping actuator for stopping the engine when power is cut off, a fuse for preventing overcurrent provided between the engine stopping actuator and a power source, and a gear shift position operating actuator. 2. The engine emergency stop device for an automatic work vehicle according to claim 1, wherein a fuse for overcurrent prevention provided between the power source and the power source is shared.