JPH0626458Y2 - Safety equipment for work vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Industrial field of application The present invention disables the grounding operation of the outrigger and the operation of the work device when the work auxiliary braking device is not operating on a sloping ground with a certain angle or more. The present invention relates to a safety device for a working vehicle.

(2) Related Art A work vehicle in which a work device such as a work device for aerial work is mounted on a vehicle such as a truck is conventionally known as disclosed in Japanese Utility Model Laid-Open No. 62-203198, for example. As shown in FIG. 4, outriggers (2) supporting the vehicle body (1) are provided on the front, rear, left and right sides of the vehicle body (1), and a telescopic boom (2) is provided on a turntable (3) provided on the vehicle body (1) so as to be rotatable. 4) is pivotally supported, and the telescopic boom (4) is hoisted by the telescopic cylinder (5) arranged between the telescopic boom (4) and the turntable (3) to extend and retract to the tip of the telescopic boom (4). The workbench (6) is balanced.

(3) Problems to be Solved by the Invention However, in the conventional work vehicle, the outrigger is grounded and the work device such as the telescopic boom is operated only by applying the parking brake that normally brakes the rear wheels. If the grounding operation order of the outriggers is incorrect and the rear outriggers are grounded so that the rear wheels on which the parking brakes have been braked are lifted first, the rear wheels will float. The braking force will not work on the work vehicle,
There was a problem that the work vehicle started to slide.

(4) Means for Solving Problems In order to solve the above problems, the present invention includes a main braking device for braking wheels, and a vehicle body is provided with a PTO to drive the vehicle.
In a work vehicle equipped with a pump driven by the power taken out through the pump, an outrigger operated by the pressure discharged from this pump, and a working device, the main braking device and a part of its piping are shared and the hydraulic pressure is used. Work auxiliary braking device for fixing the pressure to maintain the braking force generated by the work vehicle and keeping the work vehicle in a stopped state, a first detector for detecting the operation of the work auxiliary braking device, and connection / disconnection of the PTO. A second detector for detecting the inclination angle, an inclination angle detector for detecting the inclination angle of the vehicle body, and a signal from the first detector, the second detector, and the inclination angle detector for assisting work on a sloped land having a certain angle or more. An operation stopping device that operates when the braking device is not operating and the PTO is connected to disable the grounding operation of the outrigger and the operation of the working device.

(5) Operation With the above configuration, when the outrigger is grounded, the work auxiliary braking device is operated at the position where the work vehicle is installed, and the PTO is connected so that the operation stop device does not operate and the outrigger is operated. Can be grounded.
In addition, if the slope of the ground for grounding the work vehicle is within a certain angle, even if the work auxiliary braking device is not activated,
The operation stop device does not operate due to the signal from the inclination angle detector, and the outrigger can be grounded by connecting the PTO. However, on a slope with a certain angle or more, the PTO can be operated without operating the auxiliary braking device for work. When connected, first
Signals from the detector, the second detector and the tilt angle detector actuate the operation stopping device to disable the grounding operation of the outrigger.

(6) Embodiment An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 3, an aerial work vehicle is provided with outriggers (2) for supporting the vehicle body (1) on the left and right sides of the vehicle body (1), and a turnable turn is provided on the vehicle body (1). A table (3) is provided, and the base end of a telescopic boom (4) connected in a telescopic manner is pivotally supported on the turntable (3), and the telescopic boom (4) is extended by a telescopic device (not shown). As it expands and contracts, it expands and contracts due to the expansion and contraction of the hoisting cylinder (5), the workbench (6) is held in equilibrium at the tip of the telescopic boom (4), and the PTO is connected and disconnected in the cab (18) of the work vehicle. An operation lever (19) is provided, a second detector (20) for detecting the connection / disconnection of the PTO is attached to the operation lever (19), and the vehicle body (1) detects the inclination angle of the vehicle body (1). The tilt angle detector (21) is attached to the outrigger (2). Operation detector (30) is attached which detects the extension operation of the outriggers (2).

FIG. 2 shows a circuit diagram of an auxiliary braking device for work. The brake pedal (7), a master cylinder (8) actuated by the brake pedal (7), the master cylinder (8) and a conduit (10). ) And a hydro master (9) which is operated by the pressure oil sent from the master cylinder (8) to discharge the pressure oil, and this hydro master (9)
A front brake (11) and a rear brake (1) that actuate by pressure oil discharged from the brakes to brake each wheel.
2) and a pipeline (10) connecting the master cylinder (8) of the main braking device and the hydro master (9)
The electromagnetic switching valve (13) is inserted to prevent pressure oil supplied from the master cylinder (8) to the hydro master (9) from returning to the master cylinder (8) by operating the solenoid switching valve (13). ) Is a switch (14) that is closed by actuating a parking brake (not shown).
And that the operating switch (15) that closes when the working auxiliary braking device is actuated is actuated by the controller (16) that operates when the working auxiliary braking device is actuated, and that the working auxiliary braking device has acted on the controller (16). A first detector (17) for detecting is attached.

FIG. 1 shows a circuit diagram of a safety device, in which a pump (22) driven by an engine of a work vehicle is operated by a pipe line (23), and an electromagnetic switching valve (2) with 3 ports and 2 positions, which is an operation stopping device.
4), and the electromagnetic switching valve (24) is connected to an operation valve (not shown) that operates the telescopic boom (4) via the operation valve (25) that operates each outrigger (2). At the same time, it is connected to the return line (28) to the tank (27) by the line (26). First detector (1
7), the second detector (20), the inclination angle detector (21) and the operation detector (30) are connected to the comparator (29), and the comparator (29) is a solenoid (24) of the electromagnetic switching valve (24). 24
Auxiliary braking device for work is not operated on a sloping ground with a certain angle or more due to signals from the first detector (17), the second detector (20) and the inclination angle detector (21) connected to a). When the PTO is connected in this state, the solenoid (24a) is energized to excite the solenoid (24a) to switch the electromagnetic switching valve (24) to the (II) position, and the pressure oil discharged from the pump (21) is transferred to the pipe line (26). And the circulation to the tank (27) via the return line (28) and the operation detector (30)
When the outrigger (2) is extended by the signal from the electromagnetic switch valve (24), the electromagnetic switching valve (24) is held at the (I) position regardless of the signal from the tilt angle detector (21).

With the above configuration, when the work is performed using the aerial work vehicle, the parking brake is operated to close the switch (14), and the operation switch (15) is closed to operate the controller (16) to brake. By operating the hydro master (9) by stepping on the pedal (7) and operating the front brake (11) and the rear brake (12), the solenoid (1) is operated by the controller (16).
3) is switched, and the solenoid switching valve (13) is switched to the solenoid switching valve (1
3) The hydro master (9) is kept in the operating state by containing the pressure oil between the hydro master (9) and the front brake (11) and the rear brake (12) being kept in the operating state. When the auxiliary braking device operates and the operating lever (19) is operated in this state to connect the PTO, the comparator (29) causes the comparator (29) to receive signals from the first detector (17) and the second detector (20). Since the work auxiliary braking device is operating and the PTO is also connected, the solenoid (24) is irrespective of the signal from the tilt angle detector (21).
The electromagnetic switching valve (24) is held in the (I) position without exciting a), and the pressure oil discharged from the pump (22) is supplied to the operation valve (2).
5), the outrigger (2) is operated by operating the operation valve (25).

In addition, when working with an aerial work vehicle where the slope of the ground is within a certain angle, the parking brake is not operated, the operation switch (15) is not closed, etc. Even if the operating lever (19) is operated to connect the PTO in a state in which the device is not operated, the comparator (29) causes the first detector (17) and the second detector by the signal from the tilt angle detector (21). Regardless of the signal from the detector (20), the electromagnetic switching valve (2
4) is held in the (I) position and the pressure oil discharged from the pump (22) is sent to the operation valve (25), so that the operation valve (25)
By operating the outrigger (2),
Even if the vehicle body (1) is tilted due to the operation of the outrigger (2), the comparator (29) receives the signal from the operation detector (30) regardless of the signal from the tilt angle detector (21). 24a) without exciting the electromagnetic switching valve (2
Since 4) is held at the (I) position, the operation of the outrigger (2) will not be disabled. Further, when the work is carried out using the work vehicle at an altitude where the inclination of the ground is a certain angle or more, the parking brake is not operated, the operation switch (15) is not closed, and the like, and the auxiliary braking for work is performed. Operate the operating lever (19) without operating the device to PT
When O is connected, the comparator (29) outputs the signal from the first detector (17), the second detector (20) and the tilt angle detector (21) to excite the solenoid (24a), The electromagnetic switching valve (24) is switched to the (II) position, and the pressure oil discharged from the pump (22) is circulated to the tank (27) via the pipeline (26) and the return pipeline (28). Therefore, even if the operation valve (25) is operated, the outrigger (2)
Does not work.

In the above embodiment, the work auxiliary braking device is not operated on a sloping ground with a certain angle or more, and is operated when the PTO is connected to stop the operation of the outrigger grounding and the work device. Although a device equipped with a device has been described, an alarm device that informs the worker of danger is provided instead of the operation stop device, when the auxiliary braking device for work is not operating on a slope with a certain angle or more and the PTO is connected. It is also possible to issue an alarm to the device, and it is possible to provide both an operation stop device and an alarm device.

(7) Effects of the Invention As described above, according to the present invention, the work auxiliary braking device that holds all the wheels in a braking state is provided, and the work auxiliary braking device operates only on a sloping ground with a certain angle or more. If the PTO is connected without it, the operation stop device will operate and the operation of the outrigger and the work device will be disabled, so the work auxiliary braking device should not be operated when the slope of the ground is within a certain angle. A safety device for a work vehicle is provided, which can operate an outrigger and a work device, and prevents the work vehicle from slipping even when working on a slope with a certain angle or more. Is effective in improving.

[Brief description of drawings]

The drawings show an embodiment of the present invention. Fig. 1 is a circuit diagram of a safety device, Fig. 2 is a circuit diagram of a work auxiliary braking device, Fig. 3 is a side view of an aerial work vehicle, and Fig. 4 is conventional. It is a side view of the aerial work vehicle. 1 ... Car body, 2 ... Outrigger, 17 ... First detector,
20 ... Second detector, 21 ... Inclination angle detector, 22 ...
... pump, 24 ... electromagnetic switching valve, 24a ... solenoid, 25 ... operating valve, 26 ... pipeline, 27 ... tank,
28 ... Return line, 29 ... Comparator.

Claims (1)

[Scope of utility model registration request] 1. A pump provided with a main braking device for braking wheels, driven by power extracted from a driving prime mover through a PTO, and an outrigger operated by pressure oil discharged from the pump and work. In a work vehicle provided with a device, an auxiliary braking device for work that shares pressure with the main braking device and a part of its piping to maintain a braking force generated by hydraulic pressure and keeps the working vehicle in a stopped state And a first detector for detecting the operation of the work auxiliary braking device,
A second detector for detecting connection / disconnection of the PTO, a tilt angle detector for detecting a tilt angle of the vehicle body, and a sloped land having a predetermined angle or more by signals from the first detector, the second detector and the tilt angle detector. And an operation stop device that operates when the work auxiliary braking device is not operating and the PTO is connected to disable the grounding operation of the outrigger and the operation of the working device. Safety equipment for working vehicles.