JPH0986900A - Boom control device of high place working truck - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out a high place work by both hands, while driving a boom drive device by one worker by holding a control signal when the input of an operation signal from a manual operation part is intercepted under such state that a control means is outputted from a controller. SOLUTION: It is judged whether a foot switch 8 is pedaled and a signals (c) is outputted. When it is outputted, the operation signal P from a manual operation part 6 is inputted and a signal in response to an inputted signal is calculated. When it is judged that the operation signal P of the manual operation part 6 is outputted continuously, a control signal in response to the operation signal P is outputted from an amplifier 9f to a boom drive device 2 and driven in response to the operation of the manual operation part 6. While, when it is judged that the operation signal P is discontinued, a signal concerning a memory is outputted to the amplifier 9f and a control signal Q in response to a memorized drive direction and speed is outputted to the boom drive device 2, after a signal concerning the drive direction and speed calculated at the discontinued time of the operation signal P is memorized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boom controller for an aerial work vehicle.

[0002]

2. Description of the Related Art An aerial work vehicle is equipped with a work table 4 at the tip of a boom 3 mounted on a vehicle 1 via a boom drive device 2 as shown in FIG. The boom drive device 2 includes a boom hoisting drive device 2a, a boom extension / contraction drive device 2b, a boom turning drive device 2c, and the like.

An aerial work vehicle of this type outputs an on / off operation signal P for controlling the boom drive device 2 which is attached to a boom control device 5 as shown in FIG. Spring return type manual operation section 6, a foot switch 8 for detecting depression of a foot pedal 7 attached to the workbench 4, an operation signal P from the manual operation section 6 and a signal from the foot switch 8 (foot pedal 7
A boom control device 5 including a controller 9 which receives and calculates a stepping signal c) of the above and outputs a control signal Q to the boom drive device 2 in accordance with an operation signal P is attached.

In this example, the manual operation section 6 of the boom control device 5 outputs an up / down operation signal Pa for controlling the drive of the boom up / down drive apparatus 2a,
A telescopic operation unit 6b that outputs an telescopic operation signal Pb for controlling the drive of the boom telescopic drive device 2b, and a swivel operation unit that outputs a swivel operation signal Pc for controlling the drive of the boom swivel drive device 2c. 6c. The hoisting and manipulating portion 6a is composed of a pair of normally open push button switches for instructing raising and lowering of the boom 3, respectively. The telescopic operation unit 6b is composed of a pair of normally open push button switches for instructing extension drive and fall drive of the boom 3, respectively. In addition, the turning operation unit 6c
Each of them is composed of a pair of normally open push button switches for instructing the boom 3 to rotate rightward or leftward.

The controller 9 includes a microcomputer 9a, IO ports 9b-9e connected to the input side of the microcomputer 9a, and a microcomputer 9a.
It is configured with an amplifier 9f connected to the output side of. The IO ports 9b, 9c, 9d and 9e are respectively provided with the undulation operation signal P from the undulation operation section 6a.
a, an expansion / contraction operation signal Pb from the expansion / contraction operation unit 6b, a rotation operation signal Pc from the rotation operation unit 6c, and a foot switch 8 (when the worker on the workbench 4 works at a high place, the ON signal is output. ), The stepping signal c is input. Further, from the output side of the amplifier 9f, a control signal Q to the boom drive device 2 (a boom hoisting control signal Qa to the boom hoisting drive device 2a, a boom telescopic control signal 2b to the boom telescopic drive device Qb, a boom turning drive). A boom turning control signal Qc) is output to the device 2c. Reference numeral 10 is a power supply for the controller 9.

By the way, the controller 9 of the conventional boom control device 5 is controlled by the microcomputer 9a so that the foot switch 8 outputs a foot pedal depression signal c.
When the operation signal P is received from the manual operation section 6 in the state where the input is input, the control signal Q corresponding to the operation signal P related to the reception is output to the boom drive device 2, and the foot switch 8 outputs the foot switch. When the input of the depression signal c is cut off, the control signal Q is disabled from being output to the boom drive device 2 (output is cut off).

The control of the controller 9 of the conventional boom control device 5 configured as described above will be described with reference to FIG.
When power is supplied to the controller 9 in step ST1, the microcomputer 9a is initialized, and a flag which is inverted each time the stepping signal c from the foot switch 8 is repeatedly turned on and off is initially set to zero. In step ST2, the microcomputer 9a determines whether or not the foot switch 8 is stepped on and the on (depression) signal c is output from the foot switch, and when it is determined that the on signal is not output, the microcomputer 9a determines in step ST2.
In step ST10, the flag is set to 1, and in step ST10, the signal output to the amplifier 9f is set to 0.

On the other hand, when the microcomputer 9a determines in step ST2 that the foot switch 8 is outputting the on (stepping) signal c, it further determines in step ST3 whether the flag is 1 or 0, and the flag is If it is determined to be 0, the operation signal P (Pa, Pb, Pc) from the manual operation unit 6 is input through the IO ports 9b to 9d in step ST4. In the next step ST5, a signal corresponding to the input operation signal P is calculated, and then a signal related to the calculation is output to the amplifier 9f in step ST6, and the amplifier 9f sends a signal to the boom drive device 2 in response to the operation signal P. The control signal Q is output to drive the boom drive device 2 according to the operation of the manual operation unit 6.

The signal corresponding to the operation signal P calculated in step ST5 is an ON signal for instructing the driving direction of the boom drive device 2, so the boom drive device is in the direction instructed by the ON signal. 2 is used to calculate a signal required to drive a predetermined speed. As the signal relating to the driving speed calculated at this time, speed information stored in advance in the microcomputer 9a is used. Of course, as the speed information used at this time, an electric signal from a drive speed setting means (potentiometer whose output voltage can be manually adjusted) separately mounted near the manual operation part 6 of the workbench 4 may be used. The drive speed setting means and the A / D converter in this case are shown by imaginary lines in FIG.
Reference numerals 11 and 12 are attached respectively.

On the other hand, if the microcomputer 9a determines that the flag is 1 in step ST3, it determines in step ST7 based on the signal from the manual operation part 6 whether the manual operation part 6 is operated or not. When it is determined that the operation unit 6 is not operated, the flag is set to 0 in the next step ST8, and the step ST
Return to 2. If it is determined in step ST7 that the manual operation unit 6 is operated, the above-mentioned step S
Return to T2.

In the conventional boom control device 5 thus constructed, the boom drive device 2 cannot be started even if the manual operation portion 6 is operated unless the foot pedal 7 is depressed.
Moreover, when the foot pedal 7 is released, the control signal Q to the boom drive device 2 is cut off and the operation of the boom drive device 2 is stopped, so that work at high places can be performed safely.

[0012]

However, in the case of performing painting work or maintenance / inspection work on the wall surface by a single worker on the workbench 4, in the conventional boom control device described above, the manual operation unit is used. When the hand is released from 6, the operation signal P from the manual operation section 6 is cut off (non-operation state), and accordingly the control signal Q from the controller 9 is cut off. Therefore, the boom drive device 2 is driven and the workbench 4 is moved. There was a problem that the worker could not perform painting work or high-altitude work such as maintenance / inspection work with both hands while moving.

The present invention solves the problems of the conventional boom control device 5 described above, and the operator releases the manual operation part 6 so that the operation signal P from the manual operation part 6 is in the non-operation state. Even so, it is intended to provide a boom drive device capable of maintaining the output of the control signal Q from the controller 9.

[0014]

In order to solve the above problems, the boom control device for an aerial work vehicle of the present invention is configured as follows to solve the above problems. A boom control device for an aerial work vehicle comprising a workbench 4 at the tip of an extendable boom 3 movably mounted on a vehicle 1 via a boom drive 2 and mounted on the workbench 4. A spring-return type manual operation unit 6 for outputting an on / off operation signal a for controlling the boom drive, a foot switch 8 for detecting depression of a foot pedal 7 attached to the workbench 4,
The controller 9 is provided with a controller 9 that receives an operation signal from the manual operation unit 6 and a signal from the foot switch 8 and calculates and outputs a control signal according to the operation signal to the boom drive device 2. When an operation signal is received from the manual operation unit 6 while the foot pedal depression signal is being input from the switch 8, a control signal is sent to the boom drive device 2 according to the operation signal related to the reception.
The controller 9 is configured so as to disable the output of the control signal to the boom drive device 2 when the input of the foot switch depression signal from the foot switch 8 is interrupted (output is interrupted). The control signal output is maintained when the input of the operation signal from the manual operation unit 6 is interrupted while the control signal is being output from the controller 9.

[0015]

In the boom control device for an aerial work vehicle of the present invention constructed as described above, the controller 9 outputs a control signal (the controller 9 receives a stepping signal c from the foot switch 8). When the input of the operation signal P from the manual operation unit 6 is cut off in a state where the operation signal P is input from the operation unit 6), the boom drive device is configured to maintain the output of the control signal Q. When the operator intends to perform high-level work such as painting work or maintenance / inspection work using both hands while driving the work table 4 while moving the work table 4, the foot pedal 7 is depressed and the manual operation section 6 is operated. Even if the hand is released from the manual operation section 6 while the boom drive device 2 is being driven appropriately, the boom drive device 2 can continue to drive the boom 3 as long as the foot pedal 7 is depressed. Than it is. Therefore, according to the boom control device for an aerial work vehicle according to the present invention, one worker can perform painting work or maintenance / inspection work with both hands while continuously driving the boom drive device 2. Therefore, the work efficiency can be dramatically improved. When the output of the control signal Q from the controller 9 is to be stopped, the depression of the foot pedal 7 may be stopped.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a boom control device for an aerial work vehicle according to the present invention will be described below with reference to FIG. The boom control device of the present invention is different from the conventional boom control device shown in FIG. 3 to FIG. 4 only in that the control characteristics of the controller 9 are partially changed. Regarding the configuration and the operation, those used in the above description of the conventional art are cited.

FIG. 1 is a control characteristic diagram of the controller 9 in the boom control device according to the present invention. As shown in FIG. 1, the boom control device of the present invention includes steps ST5 and ST in FIG. 4 for explaining the control of the conventional controller 9.
6, a step ST5 'for determining whether or not the operation signal P is input from the manual operation section 6 is added. In step ST5 ', when it is determined that the operation signal P is continuously input, the process proceeds to step ST6, and when it is determined that the operation signal P is interrupted, the process proceeds to step STx. In step STx,
After the signal regarding the driving direction and the driving speed calculated in step ST5 when the operation signal P is interrupted is stored (stored in the microcomputer 9a), the signal related to the storage is output to the amplifier 9d in step STy, and the amplifier 9d is output.
The control signal Q is output from d to the boom drive device 2 according to the drive direction and drive speed related to the memory, and the boom drive device 2 is driven according to the operation of the manual operation unit 6.

In the above embodiment, the boom hoisting drive device 2a and the boom extension / contraction control device 2 in the boom drive device 2 are used.
b, the boom turning control device 2c, the manual operation unit 6 respectively.
In the above description, it is assumed that the boom control device of the present invention is controlled by the up / down operation signal Pa from the up / down operation section 6a, the expansion / contraction operation signal Pb from the expansion / contraction operation section 6b, and the rotation operation signal Pc from the rotation operation section 6c. The manual operation part 6 is provided with a workbench vertical elevating operation part for instructing a vertical elevating operation of the workbench 4, and the controller 9a is provided with a boom hoisting angle detector for detecting a hoisting angle Θ of the boom 3 and a boom length L. A boom length detector (neither of which is shown) for detecting the movement is provided, and the boom raising / lowering drive device 2a and the boom extension / contraction drive device 2b are simultaneously driven by a single operation signal from the work platform vertical elevating / lowering operation part. It may be applied to the one in which the table 4 is vertically driven. In this case, the boom hoisting angle detector and the boom length detector detect the boom hoisting angle and the boom length, which are driven by the boom hoisting drive device 2a and the boom telescopic drive device 2b while maintaining Lcos Θ = constant condition. It is used to calculate and calculate the boom hoisting control signal Qa and the boom extension / contraction control signal Qb required for the above.

Further, in the boom control device of the present invention, the manual operation section 6 is provided with a workbench horizontal drive operation section for instructing horizontal drive of the workbench 4, and the controller 9a detects the hoisting angle Θ of the boom 3. A boom hoisting angle detector and a boom length detector (neither shown) for detecting the length L of the boom are provided, and the boom hoisting drive device 2a is operated by a single operation signal from the workbench horizontal drive operation unit. Alternatively, the boom telescopic drive device 2b may be simultaneously driven to horizontally drive the work table 4. In this case, the boom hoisting angle detector and the boom length detector detect the boom hoisting angle and the boom length which are driven by the boom hoisting drive device 2a and the boom telescopic drive device 2b while maintaining a condition of Lsin Θ = constant. It is used to calculate and calculate the boom hoisting control signal Qa and the boom extension / contraction control signal Qb required for the above.

[0020]

The boom control device for an aerial work vehicle of the present invention configured as described above is in a state in which a control signal is output from the controller 9 (a state in which the stepping signal c from the foot switch 8 is input to the controller 9). When the input of the operation signal P from the manual operation unit 6 is interrupted in a state where the operation signal P is input from the manual operation unit 6 in (1), the output of the control signal Q is maintained. When the operator intends to perform high-level work such as painting work or maintenance / inspection work with both hands while driving the device 2 and moving the workbench 4, the manual operation part is depressed with the foot pedal 7 depressed. Even if the operator manually operates the boom drive device 2 and releases the hand from the manual operation part 6 while the boom drive device 2 is being driven appropriately, the boom drive device 2 drives the boom 3 as long as the foot pedal 7 is depressed. Than it is maintained. Therefore, according to the boom control device for an aerial work vehicle according to the present invention, one worker can perform painting work or maintenance / inspection work with both hands while continuously driving the boom drive device 2. Therefore, the work efficiency can be dramatically improved. When it is desired to stop the output of the control signal b from the controller 9, the depression of the foot pedal 7 may be stopped.

[Brief description of drawings]

FIG. 1 is a control characteristic diagram of a boom control device for an aerial work vehicle according to the present invention.

FIG. 2 is an explanatory view of an aerial work vehicle.

FIG. 3 is an explanatory view of a conventional boom control device for an aerial work vehicle.

FIG. 4 is a control characteristic diagram of a boom control device for a conventional aerial work vehicle.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1; Vehicle, 2; Boom drive device (2a; Boom up-and-down drive device, 2b; Boom telescopic drive device, 2c; Boom swing drive device), 3; Boom, 4; Workbench, 5; Boom control device, 6; Manual Operation part (6a; undulation operation part, 6b; telescopic operation part, 6c; turning operation part) 7; foot pedal, 8; foot switch, 9; controller, 9a; microcomputer, 9b to 9e; IO
Port, 9f; amplifier, 10; power supply, 11; drive speed setting means, 12; A / D converter, P; operation signal (Pa; undulation operation signal, Pb: expansion / contraction operation signal, Pc: turning operation signal), Q Control signal (Qa; boom up / down control signal, Q
b: boom expansion / contraction control signal, Qc: boom turning control signal), c: stepping signal,

Claims (1)

[Claims] 1. A workbench 4 is attached to the tip of a telescopic boom 3 which is mounted on a vehicle 1 so as to be driven by a boom drive device 2.
A boom control device for an aerial work vehicle, comprising: a spring-return type manual operation unit 6 which is attached to the workbench 4 and outputs an on / off operation signal P for controlling the boom drive; A foot switch 8 for detecting the depression of the attached foot pedal 7, an operation signal from the manual operation part 6 and a signal from the foot switch 8 are received and calculated, and a control signal corresponding to the operation signal is sent to the boom drive device 2. When the controller 9 receives an operation signal from the manual operation section 6 in a state where a foot pedal depression signal is input from the foot switch 8, the controller 9 responds to the operation signal related to the reception. The control signal is output to the boom drive device 2, and when the input of the foot switch depression signal from the foot switch 8 is cut off, the boom drive device 2 is driven. In a configuration in which the output of the control signal to the device 2 is disabled (output is cut off), the controller 9 is operated by the manual operation unit 6 while the control signal is being output from the controller 9. A boom control device for an aerial work vehicle, characterized in that the control signal output is maintained when the input of the control signal is cut off.