JP2001240395A - Safety device for working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To safely carry out working without using a dummy hook. SOLUTION: This safety device 40 for a high lift working vehicle has two safety ropes 47 fitted onto bodies of respective workers M on a working platform 23, each of which has a working platform side hook 45 in its tip, two locking member 49 provided in both left and right side parts of the platform 23 to lock the hooks 45, the first lock sensor and the second lock sensor for detecting lock of the hooks 45, and a dummy signal switch 51 for making, by a controller, judgement that the working platform side hook 49 not locked to the locking member 49 is locked to the member 49 by an operation of the worker M on the platform 23, when that any of the hooks 45 is not locked to the locking member 49 is detected by any of the first and second sensors.

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 a work vehicle, and more particularly, to a safety belt attached to the body of an operator on a workbench, and a hook provided at the tip of the safety belt. The present invention relates to a safety device for a working vehicle having a locking member on a worktable for locking.

[0002]

2. Description of the Related Art When an electric construction work is performed on a utility pole, an aerial work vehicle having a workbench on which a plurality of workers can be mounted is used at the tip of a telescopic boom that can be raised and lowered.
This aerial work platform is provided with a swivel base provided on the vehicle body, a telescopic boom pivotally connected to the swivel base, and a vertically movable rocker at the tip of the telescopic boom. There is a configuration including a work table provided. A safety belt is detachably attached to the body of the worker in order to further ensure the safety of the worker who has boarded the work table. A hook is provided at the tip of the safety belt, and the hook is locked to a locking member fixed to the side of the worktable to prevent the worker from falling off the worktable before working. The safety of the elderly.

[0003] The workbench is provided with a safety device. This safety device is provided with an operating device for operating the telescopic boom, the workbench, and the winch mechanism when the same number of hooks as the number of workers capable of boarding the workbench are not locked by the locking member. Regardless of the operation, the operation of the telescopic boom,
Restricts the worktable swing operation and winch mechanism operation. For this reason, it is possible to ensure the safety of all workers who board the worktable.

[0004]

However, since the safety device does not have a function of detecting the number of workers on the platform, if the number of workers on the platform is less than the capacity, If the insufficient number of dummy hooks are not locked to the locking member, the safety device operates to restrict the operation of the telescopic boom and the like. In addition, since the number of workers boarding the worktable changes according to the work content, a dummy hook must be prepared on the worktable, which may cause the dummy hook to be lost, thereby increasing the management burden. Further, when the number of workers on the workbench is less than the capacity, a safety work is required to lock the dummy hooks to the locking member before the work, and this work is troublesome for the workers. Occurs.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a safety device for a working vehicle that can easily perform a safe operation without using a dummy hook. .

[0006]

In order to solve the above-mentioned problems, a safety device for a working vehicle according to the present invention comprises a tip of a boom (for example, a telescopic boom 13 in the embodiment) provided at least on a vehicle body so as to be able to move up and down. A work table which is attached to the unit and on which a plurality of workers can board, and a hook (for example, a work table side hook 45 in the embodiment) is attached to a tip which is removably attached to the body of each worker who has boarded the work table. A working vehicle having a plurality of safety belts and a plurality of locking members provided on a work table for locking the hooks (for example,
1 is a safety device for an aerial work vehicle 1) according to an embodiment,
Engagement detecting means for detecting whether or not the hook is engaged with the engagement member (for example, the first engagement sensor 5 in the embodiment)
3, a second locking sensor 55), upper operating means (for example, the upper operating device 35 in the embodiment) provided on a work table for operating a boom and the like, and a plurality of locking members by a locking detecting means. Operation restriction control means (for example, a lock determination circuit 79 and an operation restriction circuit 83 in the embodiment) for restricting the operation of the boom and the like by operating the upper operation means unless it is detected that all the hooks are locked; In a case where the hook is not locked by the locking member, a locking determination setting means (for example, an implementation Signal switch 51 in the embodiment)
And is configured.

According to the safety device for a working vehicle having the above structure, when the hook is not locked by the locking member and the locking determination setting means is operated, the hook is engaged when this operation is performed. The locking determination that the locking member has been locked is made by the operation restriction control means. For this reason, when an operator with less than the number of persons is on the work table, even if the hook for the worker who lacks the locking member is not locked to the locking member, the locking determination setting means can be used. Just by operating, it is possible to release the operation restriction of the boom and the like by the operation restriction control means, compared to the prior art using a dummy hook,
It is possible to reduce troublesome safety work by the operator.

The object to be operated by the operation of the upper operating means is an actuator for turning the worktable in addition to the boom, and a winch attached to a sub-boom provided on the worktable for winding and unwinding the rope. And the like.

Further, in the safety device for a work vehicle having the above-described structure, a lock determination recognition means (for example, in the embodiment) which allows a worker on the ground to recognize whether or not a lock determination is made by the lock determination setting means. May be provided on the working vehicle.

An operator on the ground determines whether or not the lock determination setting means has made a lock determination via the lock determination recognition means. Since the worker on the ground cannot judge from the ground whether or not the locking judgment setting means has been operated, the operation of the locking judgment setting means from the ground can be performed by providing the locking judgment recognition means on the work vehicle. Can be checked to determine whether all workers on the platform are in a state of wearing a safety belt or whether the locking judgment setting means is operating. It is possible to confirm the state of safe work by the worker.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to FIGS. This embodiment shows an aspect of an aerial work vehicle having a worktable at a tip end of a telescopic boom that can swing and undulate on a vehicle body. Before describing the safety device of the present invention, an aerial work vehicle equipped with the safety device will be described. As shown in FIG. 1, the aerial work vehicle 1 is configured based on a truck, has a driving cabin 5 in front of the vehicle body 3, and has front and rear sides of the vehicle body 3 behind the driving cabin 5. An outrigger jack 7 that protrudes outward and stably supports the vehicle body 3 is provided.
At the rear of the vehicle body 3, there is provided a turntable 9 which projects upward and can turn. A turning motor 11 is provided in the vehicle body 3 below the turning table 9, and the turning table 9 is turned by the operation of the turning motor 11.

A base of a telescopic boom 13 formed in a telescopic manner is pivotally connected to the upper part of the swivel base 9. Telescopic boom 1
A telescopic cylinder 15 is built in the telescopic cylinder 3, and the telescopic boom 13 is configured to be telescopically moved by the telescopic operation of the telescopic cylinder 15. An up-and-down cylinder 17 is pivotally connected between the lower surface of the telescopic boom 13 and the lower part of the swivel table 9 so that the telescopic boom 13 is raised and lowered by the telescopic operation of the up-and-down cylinder 17. I have.

A vertical post 1 is provided at the tip of the telescopic boom 13.
9 is pivotably connected to the vertical post, and the vertical post 1
A horizontal arm 21 is mounted on the side of the horizontal arm 9 so as to project in the horizontal direction and to be pivotable with respect to the vertical post 19. A working table 23 having a bottomed cylindrical shape is attached to the tip of the horizontal arm 21. The worktable 23 has an area where two workers can board. A leveling cylinder (not shown) is pivotally connected between the distal end of the telescopic boom 13 and the lower part of the vertical post 19, and the vertical post 19 is held in a vertical state by the telescopic operation of the leveling cylinder regardless of the undulating angle of the telescopic boom 13. Thus, the workbench 23 is always kept horizontal.

The sub-boom 2 is provided at the tip of the vertical post 19.
5 is provided so as to be able to swing vertically. A winch 29 around which a rope 27 is wound is attached to the base of the sub-boom 25, and the tip of the rope 27 extended from the winch 29 extends to the tip side of the sub-boom 25 and is rotatably provided at the tip of the sub-boom 25. It is hung around the sheave 31 to change its direction and hang down. A hook 33 is attached to the tip of the rope 27. The telescopic boom 13 is provided on the vertical post side of the worktable 23.
An upper operation device 35 is provided which is manually operated to operate the motor and the winch 29 and to operate the swing motor (not shown) of the work table 23.

Next, the safety device 40 will be described. As shown in FIG. 2, the safety device 40 has a safety belt 42 that is detachably attached to the waist of the worker M who is on the workbench 23. The safety belt 42 has a belt 44 having a hook locking metal 41 at one end thereof, and a belt side hook 43 which is locked by the hook locking metal 41 at one end, and a workbench side hook 45 at the other end. And a safety rope 47 provided. Further, the safety device 40 includes a locking member 4 for locking the workbench side hook 45.
9, a dummy signal switch 51 shown in FIG. 4, a first locking sensor 53, a second locking sensor 55, and a controller 5.
And 7.

As shown in FIG. 3, the locking members 49 are attached to upper portions of the left and right side plates on the upper operating device 35 side of the work table 23. In FIG. 3, only the right locking member 49 is shown, and the left locking member is not shown. The right locking member 49 has an inverted U-shape in plan view,
At both ends of the bottom plate 49a, a pair of side plates 49b1 and 49b2 projecting in a direction away from the worktable 23 are provided. A locking rod 59 for locking the workbench side hook 45 is fixed between the upper portions of the pair of side plates 49b1 and 49b2. Also,
A through hole 61 is provided at each lower portion of the pair of side plates 49b1 and 49b2.
Are formed, and the side plate 49b1 having the through hole 61 is formed.
A first locking sensor 53 is attached outside 49b2.

The first locking sensor 53 comprises an oscillator 65 for oscillating light and a light receiver 67 for receiving light. The light oscillated from the oscillator 65 passes through the through hole 6 of one side plate 49b1.
It is arranged so as to pass through 1 and reach the light receiver 67 via the other through hole 61. When light is received by the light receiver 67, the light receiver 67 outputs a low-level power, and when no light is received, outputs a high-level power (hereinafter, referred to as a “locking signal”). ing. When the workbench side hook 45 is locked to the locking bar 59, the distal end of the workbench side hook 45 blocks the path of the light output from the first locking sensor 53. On the side plate of the worktable 23 outside the locking member 49, a lid 37 having a hinge and covering the locking member 49 so as to be able to open and close is provided. Although the second locking sensor 55 shown in FIG. 5 is disposed on the left side of the worktable 23, it is configured in the same manner as the above-described first locking sensor 53, and the description thereof will be omitted. As shown in FIG. 5, the first locking sensor 53 and the second locking sensor 55 are electrically connected in parallel to a power supply 63, and each of the sensors 55 and 53 has a left sensor line 69 and a right sensor line 71. It is electrically connected to the controller 57 via the controller.

As shown in FIG. 3, the dummy signal switch 5
1 is provided on the left side of the upper operation device 35 of the worktable 23,
It has a switch portion 51a that can be tilted left and right from a neutral position (a position protruding in the vertical direction), and is configured to be able to tilt the switch portion 51a leftward (in the direction of arrow A) or rightward (in the direction of arrow B) from the neutral position. ing. More specifically, as shown in FIG. 5, the dummy signal switch 51 has two switch switching units 51b and 51c, and a power supply 63 is electrically connected to the power supply terminal 73 of one of the switch switching units 51b. One of the two contacts 75 disposed on the controller 57 side is connected to the second locking sensor 55 and the controller 5.
7 are electrically connected to a left sensor line 69 that electrically connects the seven sensors. The other contact 75 is electrically connected to a right sensor line 71 that electrically connects the first engagement sensor 53 and the controller 57. Power supply terminal 7
3, a swing connection piece 77 is provided so as to be swingable. When the switch portion 51a shown in FIG. 3 is tilted in the direction A, the swing connection piece 77 swings to the lower contact 75 side in conjunction therewith. When the switch portion 51a is tilted in the direction B, the swing connection piece 77 is configured to swing in an interlocking manner toward the upper contact 75 side.

The other switch switching section 51c is electrically connected in parallel with the power supply 63 together with the one switch switching section 51b, and two contacts 75 provided on the controller 57 side are electrically connected to the controller 57. It is connected to the. The swing connection piece 77 connected to the power supply terminal 73 is configured to swing in conjunction with the swing connection piece 77 of the one switch switching unit 51b.

The controller 57 includes, as shown in FIG.
Engagement determination circuit 79, operation control circuit 81, and operation restriction circuit 8
3 are provided. FIG.
The locking signal output when the workbench hook 45 is locked to the locking bar 59 by the first locking sensor 53 shown in FIG. When the lock signal output when the lock is locked is received, if the number of the workbench hooks 45 locked to the lock bar 59 is the same as a predetermined number (that is, 2), Otherwise, it is determined that the number of the workbench hooks 45 locked by the locking bar 59 is not the same as the predetermined number (ie, 2).

The operation control circuit 81 includes a swing motor 11, a telescopic cylinder 15, and an up-and-down cylinder 17 (hereinafter referred to as "boom actuators 11, 15, 17" collectively) shown in FIG. It is written.)
And a lamp 85 for controlling the operation of the winch 29 and the swinging motor, and for informing other workers on the ground that the dummy operation is being performed when the dummy signal switch 51 is operated. Control the lighting operation of.
When the number of workbench-side hooks 45 locked to the locking member by the locking determination circuit 79 is determined to be not the same as a predetermined number (ie, two), the operation restricting circuit 83 operates the upper operating device. When the operation of the upper operation device 35 is performed, the operation of the operation control valve V for controlling the operation of the boom actuators 11, 15, 17 and the winch is controlled regardless of the operation of the upper operation device 35.

Next, the operation of the safety device 40 of the present invention will be described with reference to FIG.
This will be described with reference to FIG. First, after the aerial work vehicle 1 is moved to a position near the work site with the work table 23 and the outrigger jack 7 stored in the vehicle body 3 shown in FIG.
The outrigger jack 7 is extended to stably support the vehicle body 3. Then, one worker M (not shown) gets on the workbench 27 via the vehicle body 3 and, as shown in FIG.
A belt 44 is attached to the waist of the user. When the belt 44 is attached to the waist, the worker M moves to the belt side hook 4 of the safety rope 47.
3 is hooked to the hook hook 41, and the workbench side hook 4
5 is locked to a locking rod 59 of a locking member 49 disposed on the right side of the work table 23 shown in FIG.

When the worktable hook 45 is locked to the lock bar 59, the light output from the first lock sensor 53 is blocked by the worktable hook 45 and the first lock sensor 53 is stopped.
Detects the locked state of the workbench side hook 45 and sends this locked signal to the controller 57 shown in FIG. In this state, even if the operator M manually operates the upper operation device 35 shown in FIG. 4, the boom actuators 11, 15, 17 and the winch 2
9 does not work. This is because the first locking sensor 53 outputs a locking signal, but the second locking sensor 55 does not output this signal.
9 is determined to be not the same as the predetermined number (ie, 2) of the workbench side hooks 45, and the operation control circuit 83 is activated based on the result of the determination, and the operation control circuit 81 and the operation control valve are actuated. This is because the output line between V is electrically cut off.

Therefore, the operator operates the boom actuator 1
In order to operate 1, 15, 17 and the winch 29, the dummy signal switch 51 shown in FIG.
Perform tilt operation in the direction. When the dummy signal switch 51 is tilted, the swing terminal 77 of the switch switching section 51b shown in FIG. 5 swings downward, and the power supply 63 and the lower electrical contact 75 are electrically connected. Is transmitted to the controller 57 through the left sensor line 69. Since the transmitted power (hereinafter, referred to as “dummy signal”) is the same level of power as the locking signal, the locking determination circuit 79 shown in FIG. 4 recognizes this dummy signal as the locking signal. As a result, based on the locking signal and the dummy signal from the first locking sensor 53, the locking determination circuit 79 determines that the number of the workbench-side hooks 45 locked to the locking member 49 is a predetermined number (ie, 2)
And the operation of the operation restriction circuit 83 is stopped. In this state, when the operator M operates the upper operation device 35, the operation control circuit 81 controls the operation of the operation control valve V according to the contents of the operation, and the boom actuator 1
The operations of 1, 15, 17 and the winch 29 are controlled.

As described above, when less than the number of workers M are on the work table 23, the dummy signal switch 51
Is tilted, a locking signal for the shortage of the worker M is sent to the controller 57, so that a safe operation can be easily performed without using a dummy hook.

In the above-described embodiment, the two contacts 75 included in the switch switching section 51b shown in FIG.
Is directly connected to the left sensor line 69 and the right sensor line 71, respectively, but is not limited thereto.
As shown in FIG. 6, the first relay 8 is connected to the left sensor line 69.
7, the first relay 87 electrically connects or disconnects one contact 75a and the left sensor line 69.
The second relay 89 can be configured to electrically connect or disconnect the other contact 75b and the right sensor line 71.

With this configuration, when the swing connection piece 77 of the switch switching section 51b is switched, the first relay 87 or the second relay 89 is activated, and the left sensor line 69 or the right sensor line is operated. A dummy signal can be sent to the controller 57 via 71.

Further, in the above-described embodiment, as shown in FIG. 3, an example is shown in which the dummy signal switch 51 is provided on the work table 23, but the present invention is not limited to this. 91 can be provided. The protruding member 91 is arranged to move to a position where the path of the light output from the first locking sensor 53 is shut off when the lid 37 is closed. Therefore, by closing the lid 37,
The workbench side hook 45 can be in the same state as the state where the worktable side hook 45 is locked to the locking member 49, and can be used instead of the tilting operation of the dummy signal switch 51.

[0029]

As described above, according to the safety device for a working vehicle of the present invention, when the hook is not locked by the locking member, the locking judgment setting means is operated. When the operation is performed, the operation restriction control means makes a determination that a hook that is not locked to the locking member is locked to the locking member. In this case, even if the hook for the worker who is insufficient for the locking member is not locked to the locking member, the operation restriction by the operation restriction control means is released only by operating the locking determination setting means. This makes it possible to reduce troublesome safety work as compared with the related art using the dummy hook.

In the case where there is a lock judgment recognition means which allows an operator on the ground to recognize whether or not the lock judgment has been made by the lock judgment setting means, the operation of the lock judgment setting means is performed from the ground. By checking the presence / absence, it is possible to determine whether the safety belt is attached to all of the workers on the workbench or whether the locking determination setting means is operating. Can check the status of safe work.

[Brief description of the drawings]

FIG. 1 is a perspective view of an aerial work vehicle equipped with a safety device according to an embodiment of the present invention.

FIG. 2 shows a front view of a workbench having a safety device according to one embodiment of the present invention.

FIG. 3 is a perspective view showing a part of the safety device according to the embodiment of the present invention.

FIG. 4 shows a block diagram of a safety device according to one embodiment of the present invention.

FIG. 5 is an electric circuit diagram constituting a part of the safety device according to the embodiment of the present invention.

FIG. 6 is an electric circuit diagram constituting a part of the safety device according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Height work vehicle (work vehicle) 3 Body 13 Telescopic boom (boom) 23 Workbench 35 Upper operating device 40 Safety device 42 Safety belt 45 Workbench side hook (hook) 49 Lock member 51 Dummy signal switch (Lock) Judgment setting means) 53 First lock sensor (Lock detection means) 55 Second lock sensor (Lock detection means) 79 Lock determination circuit (Operation restriction control means) 83 Operation restriction circuit (Operation restriction control means) 85 Lamp (means for recognizing locking judgment) M Worker

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Taeko Yasushi 1010, Yamashita, Ryoke, Ryoke, Ao-shi, Saitama F-term in Aichi Corporation Ageo Works 3F333 AA08 AA19 AC20 FA08 FA34 FA36 FE01

Claims (2)

[Claims] 1. A workbench, which is mounted on at least a tip end of a boom provided on a vehicle body so as to be able to move up and down, and on which a plurality of workers can board, and which can be detachably attached to a body of each worker who has boarded the worktable. A safety device for a working vehicle, comprising: a plurality of safety belts having hooks at a tip attached to a plurality thereof; and a plurality of locking members provided on the work table for locking the hooks. Locking detecting means for detecting whether or not a hook is locked to the locking member; upper operating means provided on the work table for operating the boom or the like; Operation restriction control means for restricting the operation of the boom or the like by operating the upper operation means unless it is detected that the hooks are locked to all of the locking members; and the hooks are locked to the locking members. Place not being done And a locking determination setting means for performing a locking determination that the hook is locked to the locking member when operated by the operation restriction control means. apparatus. 2. The apparatus according to claim 1, further comprising a lock determination recognition unit that allows an operator on the ground to recognize whether the lock determination is made by the lock determination setting unit. Safety devices for work vehicles.