JP3279718B2 - Safety equipment for aerial work vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety device for mounting a work floor on a traveling vehicle so as to be able to move up and down, and preventing an aerial work vehicle having an outrigger attached to the traveling vehicle from falling.

[0002]

2. Description of the Related Art There is known an aerial work vehicle in which a work floor is provided on a traveling carriage so as to be able to move up and down, and the work floor is extended by attaching an auxiliary floor to a main body floor and foldably attaching the work floor. I have. As a safety device for preventing overturning in such an aerial work vehicle, there is known a safety device in which when the work floor is in an expanded state, the work floor can only be raised to a predetermined height position lower than the maximum height position. ing.

[0003]

In such a safety device, in order to raise the work floor to the maximum height position, the work floor must be in an unexpanded state in which the auxiliary floor is folded, and the operation is very troublesome. is there.

[0004] In order to solve this problem, an outrigger may be attached to the traveling vehicle to improve the stability so that the working floor can be raised to the maximum height position even in the expanded state.

However, the outrigger is obstructive during traveling. Therefore, the outrigger must be movable between the extended position and the retracted position, the outrigger must be in the extended position during work, and the outrigger must be in the retracted position during traveling. Operation becomes troublesome.

Accordingly, an object of the present invention is to provide a safety device for an aerial work vehicle capable of solving the above-mentioned problems.

[0007]

SUMMARY OF THE INVENTION In an aerial work vehicle in which an expandable work floor 7 is mounted on a traveling vehicle 4 having drive wheels and outriggers 5 so as to be vertically movable by an elevating mechanism 8, the outriggers 5 protrude. Means for detecting a position or a storage position, means for detecting whether the work floor 7 is in an expanded state or a folded state, means for detecting whether the work floor 7 is at or above a predetermined height,
A controller 28 for controlling the lifting and lowering operation of the lifting and lowering mechanism 8 by a signal from each means and for controlling the driving of the driving wheels;
When the work floor 7 is in the extended state and the outrigger 5 is in the stowed position, the work floor 7 can be raised to a predetermined height and can travel, and when the work floor 7 is in the expanded state and the outrigger 5 is in the extended position, the working floor 7 is raised to the highest height. A safety device for an aerial work vehicle capable of ascending to a maximum height and capable of traveling when the work floor 7 is in a folded state, regardless of other conditions, and capable of ascending to a maximum height.

[0008]

[Work] When the work floor 7 is extended and the outriggers 5 are not extended, the work floor 7 only rises to a predetermined height. If the outriggers 5 are extended in this state, the work floor 7 can be raised to the maximum height. When the work floor 7 is not expanded, the work floor 7 can be raised to the maximum height regardless of the extension and storage of the outrigger 5, and when it is safe not to fall down, the work floor 7 can be raised and lowered without extending the outrigger 5. The troublesome operation of the outrigger 5 becomes unnecessary, and in the case of a danger of falling, the work floor 7 can be prevented from falling by preventing the work floor 7 from rising, and the work floor 7 can be raised to the maximum height by extending the outrigger 5. .

[0009]

[Embodiment] As shown in FIG. 1, a traveling vehicle 4 is constructed by attaching a steering / drive wheel 2 and caster wheels 3 to a vehicle body 1, and an outrigger 5 is provided at front, rear, left and right sides of the vehicle body 1. And movably provided over the storage position,
An outrigger overhang detection sensor 6 that detects and operates when the outrigger 5 is at the overhang position is attached to the vehicle body 1.

A work floor 7 is provided on the body 1 so as to be movable up and down by an elevating mechanism 8. The elevating machine 8 is a scissors type comprising an X-shaped link pair 9 and an elevating cylinder 10. A work floor height detection sensor 11 that operates when the height is equal to or higher than a predetermined height is provided.

The work height detecting sensor 11 is provided in the work floor 7 at a position along the sliding portion 7a of one of the links 9a constituting the link pair 9, and the one link 9a slides halfway through the slide portion 7a. It is a limit switch that turns ON when it moves.

The work floor 7 is, as shown in FIG.
An auxiliary floor 13 is extended and foldably attached to both side edges of the base 2 with hinges 14 or the like, and a work floor expansion detection sensor 15 for detecting when the auxiliary floor 13 is in the expanded position is attached to the main body floor 12. .

As shown in FIG. 3, the outrigger 5 is supported on an arm 17 having a cylindrical body 16 by a support leg 18 having an adjustable length.
The cylindrical body 16 is rotatably supported on a mounting longitudinal axis 19 that is oblique to the vehicle body 1 perpendicularly. When the cylindrical body 16 is rotated to a protruding position protruding from the vehicle body 1, the support legs 18 move downward. As a result, the support legs 18 which are turned toward the vehicle body 1 and turn to the storage position as shown by the imaginary line are located upward and are separated from the travel path. The outrigger overhang detection sensor 6, which is a limit switch that is turned on when the vehicle is in the overhang position, is mounted.

FIG. 4 is a control circuit diagram.
Is connected to the extension side chamber 10a of the lifting cylinder 10 and the contraction side chamber 10b
Is connected to a tank 24 via a drain passage 23, and the lift cylinder side of the discharge passage 22 from the check valve 25 is connected to the drain passage 23 via a valve 26. The valve 26 is in a shut-off position by spring force, and Solenoid 26
When a is energized, it becomes the communication position.

By operating the operation lever 27, a work floor raising signal and a work floor lowering signal are input to a controller 28. The controller 28 controls the electric motor based on the signals of the detection sensors, the work floor raising signal, and the work floor lowering signal. The drive signal of the solenoid 20a, the drive signal of the solenoid 26a, and the drive signal of the traveling electric motor 29 are output. The driving signal of the electric motor 29 for traveling is output when the traveling signal is inputted from the traveling lever 30 to the controller 28.

Next, the output of each signal of the controller 28 will be described. (When the drive signal of the electric motor 20 is output) When the work floor raising signal is input and the detection signal is not input from the work floor extension detection sensor 15. When a detection signal is input from the work floor extension detection sensor 15, no detection signal is input from the work floor height detection sensor 11, no detection signal is input from the outrigger overhang detection sensor 6, or when a work floor raising signal is input. When a detection signal is input from the work floor extension detection sensor 15, a detection signal is input from the outrigger overhang detection sensor 6, and a work floor raising signal is input.

(When outputting an energizing signal to the solenoid 26a of the valve 26) When the work floor lowering signal is input, the energizing signal is output, whereby the valve 26 is set to the energizing position and the extension side chamber 10a of the elevating cylinder 10 is moved. The internal pressure oil flows out from the drain passage 23 to the tank 24 via the valve 26, whereby the lifting cylinder 10 is contracted by its own weight and the work floor 7 is lowered.

(When the output of the drive signal of the electric motor 20 or the energization signal of the solenoid 26a is stopped) When the work floor raising signal and the work floor lowering signal are not input. When the work floor raising signal is input, the detection signal is input from the work floor extension detection sensor 15, the detection signal is not input from the outrigger overhang detection sensor 6, and the detection signal is input from the work floor height detection sensor 11.

The driving signal of the electric motor 29 for traveling is supplied to the controller 2 when the traveling signal is inputted from the traveling lever 30.
8, the signal is not output in the following cases even if a traveling signal is input. When the detection signal is input from the work floor extension detection sensor 15, the detection signal is not input from the outrigger extension detection sensor 6, and the detection signal is input from the work height detection sensor 11.

The above operation will be described as follows. When the work floor 7 is in the folded state, the work floor 7 can be raised to the maximum height position regardless of other conditions, and can travel. When the work floor 7 is in the expanded state and the outrigger 5 is in the storage position, the work floor 7 can travel only up to a predetermined height. When the work floor 7 is in the expanded state and the outrigger 5 is in the overhang position, the work floor 7 can be raised to the highest height and can travel.

[0021]

According to the present invention, the outrigger 5 is set with the work floor 7 in the expanded state.
When the work floor 7 is not extended, the work floor 7 only rises to a predetermined height. In this state, the work floor 7 can be raised to the maximum height by extending the outrigger 5, and when the work floor 7 is not extended, the outrigger 5 can be extended and stored. The working floor 7 can be raised to the maximum height regardless of Therefore, when it is safe not to fall, the work floor 7 can be moved up and down without extending the outrigger 5, and the troublesome operation of the outrigger 5 becomes unnecessary. The work floor 7 can be raised to the highest height if the outrigger 5 is extended.

[Brief description of the drawings]

FIG. 1 is a front view of an aerial work vehicle.

FIG. 2 is a plan view of a work floor.

FIG. 3 is an explanatory diagram of an outrigger attachment portion.

FIG. 4 is a control circuit diagram.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Body, 2 ... Steering and drive wheel, 4 ... Traveling trolley, 5 ... Outrigger, 6 ... Outrigger overhang detection sensor, 7 ... Work floor,
8 lifting mechanism, 10 lifting cylinder, 11 working floor height detection sensor, 12 body floor, 13 auxiliary floor, 15 working floor extension detection sensor, 20 electric motor, 21 hydraulic pump, 26 valve , 26a: solenoid, 27: operation lever, 28: controller, 29: electric motor for traveling,
30 ... running lever.

Continued on the front page (72) Inventor Kazuyuki Yamazaki 3-20-1 Nakase, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Komatsu Manufacturing Co., Ltd. Kawasaki Plant (72) Inventor Tohru Hishiyama 3-20-1 Nakase, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Shares (56) References JP-A-58-116239 (JP, A) JP-A-4-342645 (JP, A) JP-A-4-333500 (JP, A) JP-A-4-43649 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B66F 9/24 B66F 9/06

Claims (2)

(57) [Claims] 1. An aerial work vehicle in which an expandable work floor 7 is mounted on a traveling carriage 4 having drive wheels and outriggers 5 so as to be movable up and down by an elevating mechanism 8. Means for detecting whether the work floor 7 is in an expanded state or a folded state, means for detecting whether the work floor 7 is at or above a predetermined height, and a lifting mechanism 8 based on a signal from each means. The work floor 7 can be raised to a predetermined height when the outrigger 5 is in the stowed position and the outrigger 5 is in the storage position, and the work floor 7 can be extended. When the outrigger 5 is in the extended position in the state, the working floor 7 can be raised to the highest height and can be run, and when the working floor 7 is in the folded state, the working floor 7 can be raised to the highest height regardless of other conditions. Run on Possible and to safety devices Aerial, characterized in that the. 2. A work floor raising signal and a work floor lowering signal are inputted to a controller 28 from an operation lever 27, and a traveling signal is inputted to the controller 28 from a traveling lever 30, and these signals and a signal from each means are used to raise and lower the cylinder 10. The safety device for an aerial work vehicle according to claim 1, wherein a signal is output to the electric motor 20 of the hydraulic pump 21 for use, the solenoid 26a of the valve 26, and the electric motor 29 for traveling.