JPH0730299U - Safety equipment for work vehicles - Google Patents

Abstract

(57) [Abstract] [Purpose] To obtain a safety device for a work vehicle that performs an alarm operation when an operating device that controls the drive of a work device provided on a vehicle body fails. [Structure] After the working device driving means for driving the working device such as the boom 3 changes from the uncontrollable state to the controllable state, the signal detecting means receives the operation signal from the operating device 20 for a predetermined time of several seconds. I do. Then, when the signal detection means receives an operation signal from the operation device 20 within a predetermined time due to a switch short circuit or the like in the operation device 20,
An alarm signal is output to the alarm means, and by this alarm means,
An alarm is issued by the alarm buzzer and the alarm lamp 11, or the drive of the boom 3 is stopped to issue an alarm.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a work vehicle safety device including a work device on a vehicle body.

[0002]

[Prior art]

 A work vehicle used for power distribution work, etc. is composed of a swing base mounted on the vehicle body with a boom that can be raised and lowered and expanded and contracted freely, and the work platform is attached to the tip of this boom. There are also aerial work vehicles and cable towing vehicles equipped with a cable drum towing device on the vehicle body. In these work vehicles, work devices such as booms and traction devices are also installed on the vehicle body, and hydraulic pressure supplied from a hydraulic pump driven by an engine, an electric motor, etc. is controlled by a control valve to supply and discharge the hydraulic pressure. Many are configured to work.

In such a work vehicle, a hydraulic pump, a control valve, and the like constitute work device driving means. The work device driving means is driven and controlled by an operating device provided on the vehicle body or the workbench. Drive control is also performed by a remote control device provided via a control cable connected to the vehicle body. Since this remote control device is easy to carry, it is more likely that water will enter the operating device and the circuit will short-circuit than the operating device provided on the vehicle body. Since the cable is attached / detached, water may enter the attachment / detachment part or a contact failure of the control cable may occur.

[0004]

[Problems to be solved by the device]

 Here, when using the remote operation device as described above, if a short circuit occurs in the operation device or a contact failure of the control cable occurs, a drive signal continues to be transmitted from the remote operation device to the work device driving means. There are cases. For example, when the boom operation signal is continuously transmitted from the remote control device, connect the control cable of the remote control device when the hydraulic pump is already operating, or connect the control cable of the remote control device. If the hydraulic pump is operated in the connected state, the boom suddenly operates against the operator's intention despite the operator not operating the operating device, and smooth work cannot be performed. There was a problem.

The present invention has been made in view of the above problems, and provides a safety device for a work vehicle that performs an alarm operation when an operating device that controls the drive of an operating device provided in a vehicle body fails. Is intended.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, the safety device for a work vehicle according to the present invention is provided with a work device driving means for driving a work device arranged on the vehicle body, and the work device is operated by the operation device. The drive control of the device drive means is performed. Further, a control state detecting means is provided for detecting whether the operating device drive means can be driven and controlled by the operating device or the drive control is impossible, and the control state detecting means is provided. When the control signal from the operating device is detected within a preset time after the detection signal from the control-disabled state to the control-enabled state, the signal detection means sends an alarm signal, and the signal detection means In response to the alarm signal, the alarm means activates the alarm.

[0007]

[Action]

 In such a safety device for a work vehicle, the signal detecting means receives the operation signal from the operating device for a predetermined time after the working device driving means for driving the working device changes from the uncontrollable state to the controllable state. I do. Here, when the signal detection means receives an operation signal from the operation device within a predetermined time, an alarm signal is output. This alarm signal is input to the alarm means, and the alarm means issues an alarm with an alarm buzzer and an alarm lamp, or stops the driving of the working device to issue an alarm.

[0008]

Embodiments Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. First, an example of a work vehicle having a safety device according to the present invention will be described with reference to FIG. This work vehicle is a so-called aerial work vehicle. A swivel base 8 that can freely turn horizontally with respect to the car body 1 is provided at the rear of the car body 1 of the aerial work vehicle 10. A boom 3 that is telescopically telescopically expandable is pivotally attached to the upper portion so that the boom 3 can be raised and lowered. A workbench 4 is attached to the tip of the boom 3 via a vertical post 3a, and the vertical post 3a is always held vertically with respect to the tip of the boom 3, and the workbench 4 horizontally swings with respect to the vertical post 3a. Is free.

As shown in FIG. 2, the turning operation of the turntable 8 is performed by the hydraulic motor 2 built in the vehicle body 1. Further, the hoisting operation of the boom 3 is performed by the hoisting cylinder 5, and the telescopic operation is performed by each hydraulic cylinder such as the telescopic cylinder 6 provided inside the boom 3. These hydraulic motor and hydraulic cylinder are operated by the hydraulic pressure supplied from the hydraulic pump provided in the hydraulic power unit 9 arranged on the vehicle body. As a drive source for driving this hydraulic pump, an engine also provided in the hydraulic power unit 9 is used, or the driving force of an engine (not shown) for traveling the vehicle is extracted and used. Then, the control valve 14 for controlling the supply and discharge of hydraulic oil from the hydraulic pump is operated and controlled by the remote operation device 20 or an operation device (not shown) provided on the vehicle body 1 or the workbench 4, so that the boom 3 Perform operation control.

Here, a swivel base, a boom and the like driven by a hydraulic motor, a hydraulic cylinder and the like constitute a working device described in the claims, and an engine, a hydraulic pump, and a control valve work devices described in the claims. The driving means will be configured.

In the aerial work vehicle 10 configured as described above, the operation signal from the remote control device 20 is transmitted to the controller 7 provided on the vehicle body 1 by the control cable 21 as shown in FIG. Then, the controller 7 controls the operation of the control valve 14 based on the operation signal from the remote operation device 20. A plug (not shown) is provided at the other end of the control cable 21 having the remote operation device 20 attached at one end, and can be connected to the receptacle 7a provided on the surface of the controller 7. By this connection, the operation signal can be transmitted from the remote operation device 20 to the controller 7. Therefore, by operating the remote control device 20, the boom 3 can be turned, hoisted, and extended / contracted.

The controller 7 is provided with a control state detecting means 12 and a signal detecting means 13. The control state detecting means 12 determines whether or not each operation of the boom 3 by the remote control device 20 is possible (controllable state), that is, whether the engine for driving the hydraulic pump is operating, and the control cable 21. This is for detecting whether the plug is connected to the receptacle 7a, the main switch of the remote control device 20 is turned on, or the like. Further, the signal detecting means 13 receives an operation signal from the remote operation device 20 within a preset time (predetermined time) after the control state detecting means 12 changes from the uncontrollable state to the controllable state. It is detected whether or not. Here, the preset time is a fixed time during which a normal operation is not performed after the controllable state, and 0. Short time from a few seconds to a few seconds.

That is, in a normal operation, each operation switch in the remote control device 20 is not operated immediately after the controllable state is changed to the controllable state. Therefore, when an operation signal is transmitted from the remote control device 20 within a few seconds after the controllable state is changed to the controllable state, the remote control device 20 or the plug of the control cable 21 is short-circuited or has a poor contact. It is probable that the operation signal continues to be transmitted due to problems such as the above.

Therefore, when the reception of the operation signal is detected within the predetermined time, the signal detection means 13 sends an alarm signal to the alarm means 15. The alarm means 15, which has received the alarm signal, alerts the operator by turning on the alarm lamp 11 or sounding an alarm buzzer (not shown), and at the same time, the remote operation device 20 Regardless of the operation signal, an operation stop signal for stopping each operation of the boom 3 by stopping the operation of the control valve 14 is transmitted to the control valve 14.

For example, it is assumed that there is a case where the hydraulic power unit 9 has already been operated by the switch provided on the vehicle body and the boom 3 can be operated by operating the control valve 14. In this case, the plug for the control cable 21 connected to the remote control device 20 in which the switch for transmitting the boom raising signal is short-circuited is connected to the receptacle 7a of the controller 7, or the main switch is provided. In the remote control device 20, when the main switch is turned on after the connection to the controller 7, the signal detecting means 13 receives the operation signal within a predetermined time, and therefore the alarm means 15 activates the alarm. The alarm means 15 also performs an alarm operation when the hydraulic power unit 9 is operated after the remote operation device 20 is connected to the controller 7. As a result, the operator operating the remote control device 20 can know that the remote control device has an abnormality, and the boom 3 does not suddenly operate due to the short-circuited switch. Can work on it.

When the signal detecting means does not receive the operation signal within the predetermined time, the boom 3 is operated based on the operation signal from the operation device 20 after the predetermined time has elapsed.

In the above embodiments, the case where the remote control device connected by the control cable is used as the operation device has been described, but the present invention is not limited to this, and may be applied to a vehicle body, a workbench, or the like. It can be used not only in the attached operating device, but also in a wireless remote operating device using an optical signal or the like. Further, in the above embodiment, the case where the engine is used as the drive source of the hydraulic pump in the hydraulic power unit 9 has been described, but the present invention is not limited to this, and as shown by the one-dot chain line in FIG. It can also be used in the case of the battery-powered hydraulic power unit 19 using a motor driven by a battery as a drive source of the hydraulic pump.

Further, it can be used when each working device is driven not by hydraulic drive but by an electric motor. In this case, the battery for driving the electric motor and the electric motor The control device for controlling the electric power constitutes the working device driving means.

[0019]

[Effect of device]

 As described above, in the work vehicle safety device of the present invention, the signal detection means is operated for a predetermined time after the work device driving means for driving the work device such as the boom changes from the uncontrollable state to the controllable state. Performs the operation of receiving the operation signal from the device. Then, when the signal detecting means receives an operation signal from the operating device within a predetermined time, an alarm signal is output to the alarm means, and this alarm means issues an alarm with an alarm buzzer or an alarm lamp, or the working device's alarm. The drive is stopped and an alarm is issued.

[Brief description of drawings]

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

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

[Explanation of symbols]

 3 Boom 7 Controller 7a Receptacle 9 Hydraulic Power Unit 11 Alarm Lamp 20 Remote Control Device

Claims (1)

[Scope of utility model registration request] 1. A working device arranged on a vehicle body, a working device driving means for driving the working device, an operating device for controlling the driving of the working device driving means, and the working device by the operating device. A control state detecting unit that detects whether the drive unit is in a controllable state in which drive control is possible or in a control impossible state in which drive control is impossible, and a detection signal from the control state detection unit cannot be controlled. After changing from the state to the controllable state, a signal detection unit that transmits an alarm signal when an operation signal from the operation device is detected within a preset time, and an alarm signal from the signal detection unit A safety device for a work vehicle, comprising: an alarm means for performing an alarm operation.