JPH0940396A - Emergency stop device for work vehicle - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To provide an emergency stop device for a work vehicle capable of surely stopping an operation of a boom supporting a vehicle body such as a undulation, extension and contraction, turning, and a jack supporting the vehicle body. To get SOLUTION: A boom valve 131 and a jack valve 15 for controlling the operation of a boom and a jack arranged on a vehicle body by pressing an emergency stop switch 23.
The electric power supplied to the operating devices 21 and 22 for transmitting the operation signal to 1 is cut off, and the energization to both solenoids 31 and 32 of the interlock solenoid valve for supplying the hydraulic oil to both valves 131 and 151 is also cut off. . Since each valve is a valve that is in a neutral state when an operation signal from the operating device 21 or 22 is interrupted or when both solenoids 31 and 32 are in a non-excited state, hydraulic oil to a boom or a jack is not supplied. The supply is cut off and operation stops.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
Emergency work of a work vehicle that can surely stop the operation of a hydraulic working device such as a boom that is freely arranged to extend and retract and rotate, and a jack that supports the vehicle body when using this hydraulic working device. Regarding the stop device.

[0002]

2. Description of the Related Art In an aerial work vehicle 10 shown in FIG.
A boom 13, which is an example of a hydraulic working device, is provided on the vehicle body 11. The boom 13 is configured so that it can be freely moved up and down, expanded and contracted, and swung with respect to the vehicle body 11. Further, by extending the ground plate 15a downward in front, rear, left and right of the vehicle body 11 (only the jack device disposed on the right side of the vehicle body 11 is shown in FIG. 3), the vehicle body 11 is operated when the boom 13 is operated. The vehicle body 1 resists a moment (hereinafter referred to as a “falling moment”) acting in a direction in which the vehicle body 11 falls.
Jack devices 15, 15 for stably supporting 1 are provided.

Operation of the boom 13 such as expansion and contraction and the jack 15
The control of the grounding operation is performed by operating the operation device 20 provided on the vehicle body 11 or the workbench 14. The operating device 20 is provided with a boom operating device 21 and a jack operating device 22, and these operating devices 21,
22 operation control of the boom 13 and the jack 1
The operation control of 5 is performed.

The operation of the boom 13 and the jack 15 is
The operation is performed by the operation of a hydraulic actuator such as a hydraulic telescopic cylinder that is operated by hydraulic pressure. The operation of each of these hydraulic actuators controls the operation of the boom valve 131 or the jack valve 151 in the hydraulic circuit configured as shown in FIG. Done by

The hydraulic oil is supplied to the valves 131 and 151 through the interlock solenoid valve 30 for the hydraulic oil discharged by the hydraulic pump P. The interlock solenoid valve 30 is a neutral return type valve that is in a neutral state (state shown in FIG. 2) in a non-excited state. Then, either the left or right solenoid 31, 3
The valve is operated by exciting 2 to supply and discharge the hydraulic oil of the boom valve 131 or the jack valve 151.

In the aerial work vehicle 10 configured as described above, the boom valve 131 and the jack valve 1 are provided.
Since the hydraulic oil is supplied to only one side of 51, so-called interlock control is performed, the boom 13 is operated while the jack 15 is in the grounding operation, and the grounding plate 15a is retracted while the boom 13 is operating ( (Reduction) operation is prevented.

The aerial work vehicle 10 includes operation levers 21 and 2.
The operation of the boom 13 or the operation of the jack 15 is stopped by pressing the work material or the clothes of the worker when the operation material 20 is operated against the intention of the worker who operates the operation device 20. An emergency stop switch 23 is also provided.

The emergency stop operation performed by operating the emergency stop switch 23 shuts off the exciting power supplied to the interlock solenoid valve 30 and brings both solenoids 31 and 32 into a non-excited state to bring them into a neutral state. By doing so, the supply of hydraulic oil to the boom valve 131 and the jack valve 151 is cut off.

[0009]

Here, as the emergency stop operation, not only the jack interlock solenoid valve 30 is set to the neutral state as described above, but also other means are used in combination so that the boom 13 can be operated. It is more preferable to stop the undulating / extending / extending / turning operation and the extending / contracting operation of the jack device 15 in order to ensure safety in an emergency.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an emergency stop device for a work vehicle capable of more reliably stopping the operation of a hydraulic work device such as a boom or a jack. And

[0011]

In order to achieve such an object, an emergency stop device for a work vehicle according to the present invention is
A worker operates the emergency stop means to send a work device operation signal or a jack operation signal to the work device operation control valve and the jack operation control valve for controlling the operation of the hydraulic work device or jack installed on the vehicle body. The power supply to the operating device is shut off. here,
Both control valves are neutral return type control valves that are in a neutral state when their operation signals are cut off.
The supply of hydraulic oil to the hydraulic working device and jack is cut off, and the operation stops.

The supply of hydraulic oil to both control valves is
This is done via a switching valve. This switching valve supplies working oil to the work device operation control valve or the jack operation control valve by exciting the work device side solenoid or the jack side solenoid, and becomes a neutral state when both solenoids are not excited. Each of these solenoids is excited by the electric power supplied via the working device side solenoid exciting means or the jack side solenoid exciting means. Then, by operating the emergency stop device, the power supply to both excitation means is also cut off. As a result, both solenoids of the switching valve are in a non-excited state and are in a neutral state, so that hydraulic oil is not supplied to both control valves, and the operation of the hydraulic working device and the jack is stopped.

Further, at least one of the operation control valves is provided with an operation control valve controller, and the operation control of the operation control valve having the operation control valve controller is performed based on an operation signal transmitted from the operation control valve controller. However, the operation control valve controller may be provided with output cutoff means for cutting off the transmission of the operation signal to the operation control valve. With such a configuration, when the emergency stop means is operated, the output cutoff means cuts off the transmission of the operation signal to the work equipment operation control valve or the boom operation control valve, so that the work equipment is more reliably operated. The operation of the jack or jack can be stopped.

[0014]

EXAMPLE An aerial work vehicle 10 provided with an emergency stop device for a boom work vehicle according to the present invention will be described below with reference to FIG. The aerial work vehicle 10 has a swivel base 12 on the vehicle body 11 that can be swiveled with respect to the vehicle body 11 by the rotation operation of a hydraulic motor (not shown). . This telescopic boom 1
3 is a telescopically (nested) telescopic base boom 13a, intermediate boom 13b, and tip boom 13c.
The base boom 13a is rotatably supported by being pivotally supported by the swivel base 12.

The telescopic boom 13 is telescopically operated by a hydraulic telescopic cylinder (not shown) disposed inside the telescopic boom 13.
The hydraulic expansion / contraction cylinder 17 arranged between the swivel base 12 and the base end boom 13a is moved up and down by an expansion / contraction operation. A workbench 14 is attached to the tip of the tip boom 13c so as to always maintain a horizontal state regardless of the hoisting angle of the boom 13.

In addition, at four positions on the front, rear, left and right of the vehicle body 11,
When the boom 13 is operated, the vehicle body 11 is resisted against the overturning moment.
Jacks 15 and 15 for stably supporting the motor are provided. The jack 15 has a ground plate 15a at its lower end, and extends the ground plate 15a downward against the ground G until a ground reaction force is obtained, thereby stably supporting the vehicle body 11. The expansion / contraction operation of the jack 15 is also performed by the expansion / contraction operation of a hydraulic expansion / contraction cylinder (not shown) arranged in the jack 15.

In the aerial work vehicle 10 thus constructed, the operation / control of the operating device 20 arranged on the vehicle body 11 and the workbench 14 is performed to elevate / retract the telescopic boom 13 and the swivel base 12. Turning operation,
The jack 15 is extended and retracted. The operations of the telescopic boom 13 and the swivel operation of the swivel base 12 are performed by the boom operating device 21 of the operating device 20, and the telescopic operation of the jack 15 is performed by the jack operating device 22 of the operating device 20.

Here, in addition to FIG. 1 and FIG. 2, the swivel base 12, the boom 13, and the jack 15 in the aerial work vehicle 10.
The operation control of will be described. Each hydraulic expansion / contraction cylinder and hydraulic motor are expanded / contracted and rotated by controlling the supply / discharge of the hydraulic oil discharged from the pump P driven by the pump driving engine E arranged in the vehicle body 11. This supply / discharge control is performed by the boom valve 131 and the jack valve 151.
The hydraulic oil is supplied to the valve via an interlock solenoid valve (switching valve) 30.

The interlock solenoid valve 30 is
It is a neutral return type valve that is in a neutral state (state shown in FIG. 2) in a non-excited state. Then, by energizing the boom-side solenoid 31, the hydraulic oil discharged from the pump P is moved to the left to supply to the boom valve 131, and the hydraulic oil in the jack valve 151 is discharged to the tank T.
Further, by exciting the solenoid 32 on the jack side, it is moved to the right to supply and discharge the working oil in the opposite manner to the above.

Excitation of these solenoids 31 and 32 is performed by operating the boom operating device 21 and the jack operating device 22. When the boom operating device 21 is operated to perform ups and downs, expansion and contraction, or turning, the boom side solenoid excitation switch 21a is closed (turned on) to energize the boom side solenoid excitation relay C. When the relay C is energized, the contact C1 of the relay C is closed, the power from the battery B is supplied to the boom side solenoid 31, the interlock solenoid valve 30 is moved leftward, and the pump P is connected to the boom valve. The hydraulic oil is supplied to 131.

When the jack operating device 22 expands or contracts the jack, the jack side solenoid exciting switch 22a is closed to energize the jack side solenoid exciting relay D and the switching relay F. When the relay D and the relay F are energized, the relay D
The contact D1 of is closed and the contact of the relay F is moved upward to switch the line L3 on the battery B side to the contact D1 side. As a result, the electric power from the battery B is transferred to the battery side solenoid 3
2, the interlock solenoid valve 30 is moved to the right, and hydraulic oil is supplied from the pump P to the jack valve 151.

According to the circuit thus constructed, the hydraulic oil discharged from the pump P is supplied to only one of the boom valve 131 and the jack valve 151, so that the jack 15 can be operated during the operation of the boom 13. A so-called interlock operation is performed to prevent the boom 13 from being stowed or the grounding operation of the jack 15 being performed, so that the vehicle body 11 can be prevented from becoming unstable while the boom 13 is operating. .

A so-called proportional valve is used as the boom valve 131 because it is necessary to accurately control each operation of the boom 13. Therefore, the operation control of the boom valve 131 is
A valve controller (proportional valve controller) that transmits a proportional control signal (actuation signal) of the boom valve 131 based on a boom operation signal from the boom operation device 21 instead of directly using the boom operation signal from the boom operation device 21. By 132. Therefore, when the boom operation device 21 is operated, the boom operation signal is transmitted to the valve controller 132.

When the jack operating device 22 is operated, a jack operating signal is transmitted to the jack valve 151. Both the boom valve 131 and the jack valve 151 are neutral return type valves that are in a neutral state when an operation signal is not transmitted.

As described above, each of the valves 131 and 151 receiving the operation signal controls the supply / discharge of the hydraulic oil to / from each hydraulic telescopic cylinder or the like based on the operation signal, so that the operator who operates the operating device 20 operates. The boom 13 or the jack 15 is operated in accordance with the intention. It should be noted that the operating device 20 provided on the vehicle body 11 and the operating device 20 provided on the workbench 14 have the same configuration, and transmit operation signals of the same content. Therefore, in FIG. Only the boom operating device 21 and the jack operating device 22 of the one operating device 20 are shown.

Here, the worker's clothes and work materials are
If the boom operating device 21 or the jack operating device 22 is caught, the boom 13 or the jack 15 may be operated against the operator's intention. Therefore, the operation device 20 is provided with an emergency stop device that stops the operation of the boom 13 and the jack 15 regardless of whether the boom operation device 21 and the jack operation device 22 are operated by pushing the operation device 20. It is provided.

This emergency stop device includes an emergency stop switch 2
The emergency stop switch 23 is in the closed state (ON state) in the non-push operation state, and is opened (OFF operation) by the push operation. One contact of the emergency stop switch 23 is connected to a power supply line connected to the battery B, and the other contact is connected to a line L1 connected to the boom operating device 21 and a line L6 connected to the relay A and the valve controller 132.

The first contact A1 of the relay A is provided between the battery B and the jack operating device 22. Also,
The second contact A2 of the relay A is provided between the boom operating device 21 and the relay C, and the third contact A3 is provided between the jack operating device 22 and the relay D.

When the emergency stop switch 23 is pressed,
Since power supply (energization) to the boom operating device 21 and the relay A is cut off, the boom operating signal is not transmitted, the relay A is de-energized, and the contacts A1, A2, A3 are opened ( Off) It works. First contact A1
When is turned off, the jack operation signal is not transmitted,
When the second contact A2 and the third contact A3 are turned off, the relays C and D are de-energized, the contacts C1 and D1 are turned off, and both solenoids 31 and 32 of the interlock solenoid valve 30 are de-energized. Let

Further, when the line L6 connected to the valve controller 132 is cut off, the output cutoff means 133 provided in the valve controller 132 is activated, and the proportional control signal (from the valve controller 132 to the boom valve 131 is transmitted. Shut off the operation signal).

According to the emergency stop device configured as described above, by pressing the emergency stop switch 23,
Both the solenoids 31 and 32 are de-energized, and the operation signals transmitted to the valves 131 and 151 are cut off to make the valves 30 and 131 and 151 in a neutral state, thereby making the boom 13 and the jack 15 The supply of hydraulic oil to the machine is shut off, and the operation is hydraulically stopped. In addition, the operation of the boom 13 and the jack 15 can be electrically stopped by cutting off the power supply to the operation devices 21 and 22.

In the above embodiment, the vehicle body 11
The case where the boom 13 which can be freely actuated such as ups and downs is used as the hydraulic working device arranged in the above has been described, but the present invention is not limited to such a hydraulic working device, and a so-called scissor type vertical lift is used. The device or other hydraulic working device such as a swing arm of a cable drum in a cable lager vehicle may be used.

Also, the jack 15 is provided with expandable telescopic outrigger beams on the left and right sides of the vehicle body 11 so as to withstand a larger overturning moment, and an outrigger with a jack device attached to the tip of this outrigger beam. It may be a jack, and in this case, extension / contraction control of the outrigger beam is also performed by the jack valve.

Further, in the above embodiment, the boom valve 131 is controlled by the valve controller 132. Therefore, when the emergency stop switch 23 is pushed, the output from the valve controller 132 is also output by the output cutoff means 133. Although the valve controller 132 is to be shut off, the valve controller 132 does not necessarily have to be provided, and even when the valve controller 132 is provided, the output shutoff means 133 does not necessarily need to shut off the output. A valve controller for controlling the operation of the jack valve 151 may of course be provided.

In the above embodiment, each solenoid 3
Although the power supply line L3 for exciting the motors 1 and 32 is taken directly from the battery B, each operating device 21,
As with the power supply lines L1 and L2 to the power supply line 22, the emergency stop switch 23 is turned off when pressed.
You may make it take via the contact of the relay A.

In the above embodiment, the line L4 is connected from the boom operating device 21 to the valve controller 132.
The operation signal is directly transmitted by means of the line, and the operation signal is directly transmitted from the jack operation device 22 to the jack valve 151 by means of the line L5. In these lines L4, L5 as well, the contact of the relay A is connected. You may make it through.

[0037]

As described above, the emergency stop device for a work vehicle according to the present invention can be operated by pressing the emergency stop switch to cut off the power supply to the operating device.
The operation device does not output an operation signal, and both solenoids of the interlock solenoid valve are deenergized to be in a neutral state. Further, when the work device operation control valve and the jack operation control valve are operated based on the operation signal transmitted from the valve controller, the operation signal from the valve controller is also cut off.

As a result, when the operation device is operated by the work material or the clothes of the worker being caught, and the hydraulic working device or the hydraulic jack is operated against the worker's intention, it is against the intention. An operator who notices that the operation is being performed can stop the operation of the hydraulic working device and the operation of the hydraulic jack by a plurality of means by operating the emergency stop switch, which improves safety during work. Can be achieved.

[Brief description of drawings]

FIG. 1 is an electric circuit diagram of an emergency stop device for a work vehicle according to the present invention.

FIG. 2 is a hydraulic circuit diagram of the emergency stop device for the work vehicle.

FIG. 3 is a front view of an aerial work vehicle equipped with the emergency stop device for the work vehicle.

[Explanation of symbols]

 11 vehicle body 12 swivel base 13 telescopic boom 14 work platform 16 hoisting cylinder

Claims (2)

[Claims] 1. A hydraulic working device disposed on a vehicle body, a hydraulic jack that stably supports the vehicle body by grounding operation, and a hydraulic operation device and the hydraulic jack that are operated by an operator and supplied with electric power. When an operating device that sends an operation signal for operation control and a control for supplying / discharging hydraulic oil to / from the hydraulic work device based on the operating device operation signal from this operating device, and the operating device operation signal is cut off When a neutral return type working device operation control valve that is in a neutral state and a jack operation signal from the operating device, hydraulic oil is supplied to and discharged from the hydraulic jack, and when the jack operation signal is cut off. A neutral return type jack operation control valve that is in a neutral state, and by energizing either the working device side solenoid or the jack side solenoid, A neutral state in which the discharged working oil is supplied to either one of the working device operation control valve and the jack operation control valve, and becomes a neutral state when both the working device side solenoid and the jack side solenoid are non-excited. A return type switching valve, a working device side solenoid exciting means for supplying electric power to the working device side solenoid based on a working device operation signal from the operating device, and a jack operation signal from the operating device. A jack side solenoid exciting means for supplying electric power to the jack side solenoid and an operator operated to cut off the supply of electric power to the operating device, the working device side solenoid exciting means and the jack side solenoid exciting means. An emergency stop device for a work vehicle comprising an emergency stop means. 2. At least one of the work device operation control valve and the jack operation control valve has a valve controller that transmits an operation signal to the control valve based on an operation signal from the operation device, and an operator. 2. The emergency stop device for a work vehicle according to claim 1, further comprising an output cutoff unit that cuts off transmission of an operation signal from the valve controller when the emergency stop unit is operated by.