JP2002060197A - Safety device for high lift work vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To disable a start of an engine unless a hook of a lifeline is moored to a safety belt detection device that is a lock device, to enable stable driving operation when coming into a driving state, and to enable a work supervisor to easily monitor an installing state of the lifeline. SOLUTION: This safety device brings an engine starter circuit in an electrical conduction state only when the other end of the lifeline connected to a safety belt installed to a worker's body is locked to the safety belt detection device fixed to an aerial platform. If necessary, the safety device brings an alarm such as a revolving light or a buzzer in an operating state.

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 preventing a lifeline from being forgotten to be locked in an aerial work vehicle.

[0002]

2. Description of the Related Art An aerial work vehicle has a work table attached to the tip of a moving device such as a boom, and an operator rides on the work table to perform work. Is locked to a lifeline locking device provided at an appropriate position on the workbench. This eliminates the risk of falling and allows the worker to work safely.

However, even if the lifeline locking device is provided, it is possible to operate the aerial work vehicle without locking the hooks at the ends of the lifeline, and thus work on the workbench. When workers performed unstable work, the danger of falling was still present.

Therefore, as disclosed in Japanese Utility Model Publication No. 7-20159, when the non-lock of the lifeline is detected, the alarm is activated or the movement of the aerial work vehicle is restricted to promote the non-lock of the lifeline. Technology was proposed.

[0005]

However, even in this prior art, when an alarm is activated, for example, the worker can ignore the alarm and continue working, and the movement of the aerial work vehicle can be prevented. If this is the case, it is necessary to modify the hydraulic circuit, etc., or the malfunction of the lifeline lock detection means due to vibration during driving may cause intermittent movement of the aerial work vehicle, There was a problem that the thing itself could trigger a dangerous state.

The present invention has been made by paying attention to the problems existing in the prior art as described above. The purpose is that if the hook of the lifeline is not moored to the safety belt detection device which is the locking device, the engine can not be started, and when it enters the driving state, stable driving operation becomes possible, Another object of the present invention is to provide a safety device for an aerial work vehicle that enables a work supervisor to easily monitor the state of attachment of a lifeline.

[0007]

To achieve the above object, according to the invention of a safety device for an aerial work vehicle according to the first aspect, a lifeline connected to a safety belt attached to a worker's body is provided. The engine starter circuit is configured to be in a conductive state only when the other end is locked by a safety belt detecting device fixed to a workbench.

According to the present invention, prior to the work using the aerial work vehicle, the other end of the lifeline connected to the safety belt attached to the worker's body is connected to the workbench by the safety band detection device. If it is not locked, the engine cannot be started, and thus the lifeline can be reliably locked, and once the engine is started, regardless of the detection state of the safety belt detection device thereafter, The engine is not forcibly stopped, and stable work can be performed.

In the safety device for an aerial work vehicle according to the second aspect of the invention, the other end of the lifeline connected to the safety belt attached to the worker's body is connected to the safety band detection device fixed to the work table. Only when it is locked, the engine starter circuit is made conductive, and an alarm device such as a rotating light or a buzzer is made active.

Therefore, according to the present invention, the above claim 1 is provided.
In addition to the effects described with respect to the invention described in (1), furthermore, the work supervisor can easily monitor the state of attachment of the lifeline.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. First, an aerial work vehicle equipped with a safety device according to the present invention will be described with reference to FIG. The aerial work vehicle 10 includes a movable body 11.
A turntable 12 is provided on the upper side, and a machine base 13 is placed on the turntable 12.
Are arranged to be able to turn. A boom 14 that can be extended and retracted in the axial direction and that can be raised and lowered in the vertical direction is attached to the machine base 13, and a work table 15 is automatically adjusted at the tip of the boom 14 so that the work table 15 can always maintain a horizontal posture. Installed in.

An operator 16 rides on a work table 15, where the operation panel 17 can operate all of the running of the vehicle body 11, the turning of the machine base 13, the expansion and contraction of the boom 14, and the undulation.

The worker 16 wears a safety belt 18 on his waist,
The other end of the lifeline 19 connected to the safety belt 18 is
The work is carried out by locking in the fixed position of.

Next, a safety belt detecting device 20 for locking the other end of the lifeline 19 will be described in detail with reference to FIGS. Reference numeral 21 denotes a base, which is vertically oriented with respect to the work table 15.
(Vertical direction). At a substantially central portion of the base 21, a pin 22 is provided so as to project perpendicularly to the base 21. A rocking member 23 is fitted into the pin 22 at a substantially intermediate position thereof, and can swing vertically about the pin 22. A hook 2 of a lifeline 19 is attached to one end of the rocking member 23.
A hook lever 25 capable of anchoring the hook 4 is fixed so as to form a closed loop. A balance weight 26 is formed at the other end of the rocking member 23. 27,2
Numerals 8 are stoppers which are fixed to the base 21 and regulate the swing angle of the swing member 23, and whose position can be adjusted by screws. The weight of the balance weight portion 26 is such that the hook lever 25 normally rotates upward,
3 is kept in contact with the stopper 28, and the lifeline 19
When the hook 24 is moored, the hook lever 25 pivots downward by the weight of the hook 24,
Is set so as to be able to maintain the state in which it contacts the stopper 27. At this time, the adjusting weight can be made detachable from the balance weight portion 26 to accommodate the hooks 24 having various weights. Reference numeral 29 denotes a limit switch similarly mounted on the base 21. The fixed position of the limit switch is activated by the rocking member 23 when the hook lever 25 rotates downward, and the hook lever 25 rotates upward. Sometimes the inactive position is selected. Reference numeral 30 denotes an alarm device such as a rotary light attached to the machine base 13, which may be replaced with a buzzer or the like, or may be provided with both of them.

An electric circuit which is a control device of the safety device according to the present invention will be described with reference to FIG. 31 is a key switch,
In this figure, only positions related to the engine starter circuit are displayed. When the limit switch 29 is turned on,
With contact portions 32b of the relay RY _S leading to the starter relay is connected by the coil portion 32a of the relay RY _S, contact of the relay RY _R of the coil portion 33a of the relay RY _R lead to alarms, such as a revolving light 30 and buzzer 34 Part 3
3b is connected.

Next, the operation of this embodiment will be described. When the work table 15 of the aerial work platform 10 is lowered and is near the ground, the worker gets on the work table 15. Then, the hook 24 at the other end of the lifeline 19 connected to the safety band 18 attached to the body is moored to the hook lever 25 of the safety band detection device 20. Thereby, the prevention of the fall of the original worker is achieved at first. Due to the anchoring of the hook 24, its weight acts on the rocking member 23, the hook lever 25 pivots downward, and the limit switch 29
N (see FIG. 3). By ON of the limit switch 29, the contact portion 32b of the relay RY _S leading to the starter relay is connected by the coil portion 32a of the relay RY _S,
When the operator operates the key switch 31, the engine can be started. Furthermore, relay RY
_Since the contact portion 33b of the relay RYR connected to the alarm device such as the rotating light 30 and the buzzer 34 is also connected by the coil portion 33a of the _R , the rotating light 30 and the buzzer 34 are activated, and the supervisor on the ground side can work. Person 16 attaches lifeline 19 to safety belt detecting device 2
It can be confirmed that it is properly locked at 0.

Next, when the worker does not lock the hook 24 of the lifeline 19 to the safety belt detecting device 20, the relay RY
_Since the contact portion 32b of _S remains open, the engine cannot be started even if the key switch 31 is operated. The worker 16 immediately recognizes that, and the lifeline 1
The operation of anchoring the hook 24 of the ninth to the hook lever 25 is performed, thereby enabling safe work.

According to this technique, when the lifeline 19 is not locked, only the operation of the starter motor of the engine is invalidated in the operating portion of the aerial work vehicle 10, so that attention must be paid to the lifeline lock before starting work. It is possible to prompt the operator, and once entering the working state, the operation of the aerial work platform 10 is not inadvertently forcibly stopped due to a malfunction or the like of the safety zone detecting device 20 due to vibration or the like. Also, if the worker intentionally removes the hook 24 of the lifeline 19 during the work, the aerial work vehicle 10
Can be continued, but at that time (invention of claim 2), since the operation of the alarm 30 is stopped,
The supervisor can recognize this and immediately pay attention to the workers.

The present invention is not limited to the above-described embodiment, but can be implemented with the following modifications.

In the above embodiment, an example is shown in which the present invention is applied to an aerial work vehicle having a direct-acting boom, but the present invention is applied to an aerial work vehicle having a center-bend boom or a scissor-type aerial work vehicle. The present invention can also be applied to an order picker that allows an operator to ride on a cargo handling device and take in and out luggage from a shelf.

In the above embodiment, the engagement of the rocking member of the safety belt detecting device is detected by the limit switch, but the tilting position of the rocking member is detected by using a potentiometer or a proximity switch. The present invention can also be implemented in such a manner.

[0022]

As described above, according to the present invention, the locked state of the lifeline can be confirmed prior to the start of work, so that safer work can be performed and the safety awareness of the worker can be raised. Also, since there is no unexpected stoppage of the aerial work vehicle due to vibration etc. during work, unstable movement of the aerial work vehicle itself can be prevented, and safe work can be continued,
Furthermore, even if the worker intentionally releases the lock of the lifeline, the supervisor can easily recognize that, and the worker can be instructed in a timely manner. In addition, there is an effect that such an effect can be obtained only by adding a simple device without modifying the hydraulic circuit or the like.

[Brief description of the drawings]

FIG. 1 is an overall view showing an aerial work vehicle.

FIG. 2 is a front view showing the safety belt detection device when the lifeline is not locked.

FIG. 3 is a front view showing the safety belt detecting device when the lifeline is locked.

FIG. 4 is an electric circuit diagram of the control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Aerial work platform 15 Work table 18 Safety belt 19 Lifeline 20 Safety belt detection device 23 Rocking material 24 Hook 25 Hook lever 26 Balance weight part 29 Limit switch 30 Alarm

Claims (3)

[Claims] 1. A safety device for an aerial work vehicle in which a workbench is disposed on a vehicle body via a moving device, and a worker on the workbench performs an aerial work. The other end of the lifeline connected to the safety belt attached to the body is detachably locked to the safety band detection device fixed to the work table, and the safety band detection device confirms that the other end of the lifeline is locked. A safety device for an aerial work vehicle, wherein an engine starter circuit is brought into a conductive state by detecting. 2. A safety device for an aerial work vehicle in which a workbench is disposed on a vehicle body via a moving device, and a worker on the workbench performs an aerial work. The other end of the lifeline connected to the safety belt attached to the body is detachably locked to the safety band detection device fixed to the work table, and the safety band detection device confirms that the other end of the lifeline is locked. A safety device for an aerial work vehicle, wherein the detection device makes an engine starter circuit conductive and an alarm device is activated. 3. The safety belt detecting device is supported at one point so as to be able to swing up and down with respect to the base, and has a hook lever at one end of which the hook of the lifeline can be moored with the fulcrum interposed therebetween, and the other end thereof. The safety device according to claim 1, further comprising: a swing member having a balance weight portion; and a limit switch that is activated when the hook lever side of the swing member is tilted downward.