JP2550360Y2 - Working device safety equipment - 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 a working device whose operation is controlled through operation of an operating device.

[0002]

2. Description of the Related Art A working device is provided with an operating device having an operating lever or the like that can be arbitrarily operated by an operator and outputting an operating signal in accordance with the operation of the operating lever or the like. And
An operation signal output from the operating device is once input to a control signal output unit attached to the working device, converted into a control signal suitable for controlling the working device, and then directly controlled to operate the working device. Input to the means.

[0003]

However, when the control signal is output via the control signal output means, the control signal is output even though the operating device is not operated due to malfunction or failure of the control signal output means. There is a possibility that a control signal is output from the output means and the working device is activated.

[0004] The present invention has been made in view of such circumstances, and provides a working device safety device that can reliably prevent the operation of the working device when the operating device is not operated. It is intended to be.

[0005]

In order to achieve the above object, a safety device according to the present invention is arranged such that when an operation signal is not input to a control signal output means, a control signal is output from the control signal output means. There is provided a determining means for determining whether or not the output has been performed. When the determination means determines that the control signal is output from the control signal output means even though the operation signal is not input to the control signal output means, the control signal is output to the control means. It also has an output control means for controlling the output.

[0006]

In such a safety device, when the control signal output means outputs a control signal due to malfunction or failure when the operation device is in an unoperated state and does not output an operation signal, the determination means performs In addition to the determination, the output restricting means restricts the output of the control signal to the control means. Thereby, even if the control signal is output,
The actual operation of the work implement is prevented.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. First, FIG. 1 shows an aerial work vehicle (working device) 10 provided with the safety device according to the present invention. At the rear of the vehicle body 11 of the aerial work vehicle 10, a swivel base 12 that can freely perform a horizontal turning operation with respect to the vehicle body 11 is attached. A boom 13, which is configured to be telescopically extendable and retractable, is attached to the upper portion of the swivel base 12 so as to be able to move up and down. The turning operation of the turntable 12 is performed by operating a hydraulic turning motor 14 built in the vehicle body 11. The raising / lowering operation of the boom 13 is performed by a hydraulic raising / lowering cylinder 15 attached between the swivel table 12 and the boom 13 and a hydraulic telescopic cylinder 16 built in the boom 13 (hereinafter, these are collectively referred to as a hydraulic actuator). It is performed by operation.

A work table 17 is horizontally mounted at the tip of the boom 13, and an operation device 18 is mounted on the work table 17. The operating device 18 has a plurality of operating levers 18a, and each operating lever 18a
An operation signal is output according to the operation of a. An operation signal output from the operation device 18 is transmitted to a boom control device 19 mounted on a side surface of the swivel base 12 via a signal line (not shown) extending inside the boom 13. here,
As shown in FIG. 2, the boom control device 19
9a, a control signal output circuit 19b, and a control circuit 19c. The input circuit 19a has a role of receiving an operation signal and taking it into the boom control device 19. The control signal output circuit 19b appropriately processes the operation signal input through the input circuit 19a and outputs a control signal. The control circuit 19c controls each of the hydraulic actuators 14 based on the control signal output from the control signal output circuit 19b.
16 (switching control of a hydraulic control valve or the like, not shown).

According to such a boom control device 19,
The operator operates the operation lever 18a to turn the turntable 12.
The operation of the boom 13 can be arbitrarily controlled. However, if the control signal is output from the control signal output circuit 19b even though the operation signal is not received (input) in the input circuit 19a, the operator can control the stop of the operation of the boom 13 and the like. Disappears. Therefore, the aerial work vehicle 10 is provided with the safety device according to the present invention.

The safety device 20 includes a judgment circuit 21 and an output regulation circuit 22. The determination circuit 21 determines whether or not the operation device 18 has transmitted the boom control device 19 from the input device 19a to the control signal output circuit 19b.
It is determined whether or not an operation signal is input to the (control signal output circuit 19b). Further, when it is determined that the operation signal has not been input, the control signal output circuit 19b
To determine whether a control signal is output to the control circuit 19c. Then, when it is determined that the control signal is output from the control signal output circuit 19b even though the operation signal is not input to the boom control device 19, the control signal is output.

The output control circuit 22 is a control signal output circuit 1
Control signal line 19 from 9b to control circuit 19c
When the regulation signal output from the determination circuit 21 is not input, the control signal line 19d is opened to allow input of an operation signal to the control circuit 19c. On the other hand, when the regulation signal is input, the control signal line 19d is cut off to regulate the input of the operation signal to the control circuit 19c.

According to the safety device 20 configured as described above, since the control signal output circuit 19b malfunctions or breaks down, the control signal output circuit 19b does not operate even if the operation device 18 is not operated. Even if the control signal is output, the input of the control signal to the control circuit 19c can be prevented. Therefore, it is possible to reliably prevent a situation in which the boom 13 and the like come out of the control of the operator and operate without permission.

Although the above embodiment has been described with reference to an aerial work vehicle as an example, the safety device according to the present invention can be applied to other work devices.

[0014]

[Effect of the invention] As described above, in the safety device of the invention,
If a control signal is output from the control signal output unit even though no operation signal is input to the control signal output unit from the operation device, the output is regulated, and the control signal is transmitted to the working device. Not entered. For this reason, even if such a situation occurs due to malfunction or failure of the control signal output means, the actual operation of the working device can be prevented, and work safety can be ensured.

[Brief description of the drawings]

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

FIG. 2 is a configuration diagram of the safety device.

[Explanation of symbols]

 18 Operating device 19 Boom control device 20 Safety device

Claims (1)

(57) [Scope of request for utility model registration] 1. A control signal output means for outputting a control signal based on an operation signal input from an operation device, and a control means for controlling an operation of a work device in response to a control signal output from the control signal output means. A safety device for a working device, comprising: when the operation signal is not input to the control signal output means, it is determined whether or not the control signal is output from the control signal output means. Determining means for performing, when it is determined that the control signal is output from the control signal output means even though the operation signal has not been input to the control signal output means, A safety device for a working device, comprising: output control means for restricting an output of the control signal to the control means.