JPH0351400Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a work equipment operating device for a hydraulic power swivel with improved operability.

Conventional technology When excavating with a conventional hydraulic power shovel,
Strong digging power and high speed are required to increase work efficiency. In addition, when performing skimming work or slope excavation, fine operations are required to improve work accuracy.
A work machine operating device that satisfies these requirements at the same time is required.

Problems that the invention aims to solve However, conventional work equipment operating devices have both fine control and high-speed operation areas in a single work equipment control valve, so when performing high-speed work, it is necessary to must pass through the operating area,
There were problems such as a wasteful operation stroke was required during high-speed operation, and a sufficient operation stroke could not be taken during fine operation, resulting in poor fine operability.

This invention was made for the purpose of improving the above-mentioned problems.

Means and action for solving the problem: A position detector that detects the operating position of the work equipment operating lever, a selection switch that selects a work mode according to the work content, and a switch that selects a work mode according to the work mode selected by the selection switch. a control device that selects a work machine speed with respect to the amount of operation of a control lever, and outputs a work machine speed command along a gain curve selected according to the amount of operation of the control lever; A hydraulic power swivel work machine that is equipped with a work machine operation valve that controls the work machine cylinder based on commands, and allows fine operations to be easily performed by selecting the work mode with a selection switch depending on the work content. Operating device.

Embodiment An embodiment of this invention will be described in detail with reference to the drawings. In the figure, reference numeral 1 denotes a work equipment operating lever installed in the driver's cab of a hydraulic power shovel (not shown), and a potentiometer at the base detects the amount of operation. Position detectors 2 such as the above are linked, and the working mode can be arbitrarily selected by a selection switch 3. That is, the selection switch 3 has, for example, five contacts 3 ₁ to 3 ₅ , and for example, when contact 3 ₁ is selected, the work machine speed (Vsi) with respect to the operating stroke (x%) of the operating lever 1 is determined as shown in FIG. of
The gain curve is shown as K ₁ , and at the contact point 3 ₂ , it becomes K ₂ ,
Then, at _{the contact point 35, it becomes K5, and the control device 4 can obtain an arbitrary work machine speed command Vsi from the gain curves K1 to K5 only by operating} the switch.

The work machine speed command Vsi obtained by the control device 4 is output to the work machine operation valve 5, and the work machine operation valve 5 controls the work machine (not shown) via the work machine cylinder 6 as follows.

Next, to explain the operation, in the case of work that requires fine operation such as plowing or slope excavation, the work mode selects gain curve K ₁ , which has a slow work machine speed relative to the stroke of operation lever 1. switch 3
Select by. The data Ki selected by the selection switch 3 and the amount of operation of the operating lever 1 are input to the control device 4, and the operating amount of the operating lever 1 is inputted to the control device 4 by a function generated from a function generator 7 provided in the control device 4.
A work machine speed command is issued for the manipulated variable.

On the other hand, in order to protect the various hydraulic equipment and work machines that make up the work machine circuit, and to prevent the soil scooped up by the bucket from spilling, it is necessary to reduce the sudden increase and deceleration of the work machine.

Therefore, take the following measures.

The maximum speed at which the driver operates control lever 1 now.
If V _Ln , the work machine speed Vsi will be dVsi/dt=Ki·V _L , which corresponds to the case where the acceleration of the work machine changes in a stepwise manner.

Furthermore, if impact is evaluated using the differential value of acceleration, if the value is less than a certain value Jmax, rapid deceleration of the working machine can be alleviated.

Therefore, the work machine speed command Vsi outputted from the function generator 7 is passed through the first-order low-pass filter 8.

Now, if the time constant of the low-pass filter 8 is T, the response of the work machine acceleration is Therefore, Jmax=Ki・V _Ln・1/T ∴T=Ki/Jmax・V _Ln , and the work machine speed command is modulated by passing through the low-pass filter 8 whose time constant is determined by the work machine speed gain curve Ki. Urating makes it possible to reduce the sudden increase in speed of the work machine in any selected mode. The modulating speed command signal that has passed through the low-pass filter 8 is output to the work equipment operation valve 5, and by controlling the work equipment operation valve 5, fine control of the work equipment is possible via the work equipment cylinder 6. .

Furthermore, by using a constant flow control valve that is less susceptible to speed fluctuations due to changes in the load of the work equipment or changes in the discharge pressure of the hydraulic pump as the work equipment operation valve 5, fine controllability can be further improved. .

On the other hand, when performing heavy excavation or when a high working speed is required, the work mode is such that the selection switch 3 selects a gain curve such as K ₅ , which has a fast work machine speed relative to the operation amount of the operating lever 1, and performs the work. It will be possible to increase cutting force and improve work efficiency.

Effects of the invention As detailed above, this invention allows you to easily obtain the work machine speed according to the work content by selecting the work mode according to the work content.
Work that requires fine operation such as plowing and slope excavation can be easily performed, and even heavy excavation or high-speed excavation can be performed without going through the fine operation area as in conventional methods, so the operation lever can be used easily. This eliminates unnecessary operations and improves operability and work efficiency.

Additionally, by modulating the work machine speed command using a low-pass filter whose time constant is determined by the gain curve and outputting it to the work machine control valve, rapid increases and decelerations of the work machine can be alleviated. This prevents the dirt and sand scooped up by the bucket of the working machine from spilling out, and also protects the working machine since no excessive impact force is applied to the working machine itself.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention, with FIG. 1 being a schematic configuration diagram, FIG. 2 being a diagram showing the relationship between the operating stroke of the operating lever and the speed of the work machine, and FIG. 3 being an explanatory diagram of the operation. 1 is a work equipment operating lever, 2 is a position detector, 3 is a selection switch, 4 is a control device, 5 is a work equipment operating valve,
6 is the work machine cylinder.

Claims (1)

[Scope of utility model registration request] A position detector 2 detects the operation position of the work equipment operation lever 1; a selection switch 3 selects a work mode according to the work content; and a selection switch 3 that operates the operation lever 1 according to the work mode selected by the selection switch 3. Select the work machine speed for the amount, and press operation lever 1.
a control device 4 that outputs a work machine speed command along a gain curve selected according to the operation amount of the work machine speed command, and modulates the work machine speed command with a low-pass filter 8 whose time constant is determined by the gain curve; , a work machine operating valve 5 for controlling a work machine cylinder 6 based on a work machine speed command output from a control device 4.