JPH0626574Y2 - Operating circuit for hydraulic hammer and hydraulic auger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an operating circuit for a hydraulic hammer and a hydraulic auger in a pile driver.

[Conventional technology]

Various operating circuits for hydraulic hammers and hydraulic augers for pile driving machines have been proposed, such as the one disclosed in Japanese Utility Model Publication No. 61-26431. The operation circuit of the hydraulic hammer and the hydraulic auger proposed in this publication has a structure as shown in FIG. 2, where a is a hydraulic cylinder for lifting and lowering the hydraulic hammer, and b and c are pipes for supplying / discharging the hydraulic cylinder a. , D is a hydraulic motor for rotating the hydraulic auger,
Reference numerals e and f denote oil supply / discharging pipelines of the hydraulic motor d. The operation circuit includes a directional control valve h for controlling the flow of pressure oil from the hydraulic pressure source g to the hydraulic cylinder a and the hydraulic motor d, and the conduits b and c of the hydraulic cylinder a or the conduit e of the hydraulic motor d. , f are selected on the downstream side of the direction switching valve h, and a selection valve i for connecting the selection valves is provided. The direction switching valve h is formed by a 4-port 2-position switching valve, and the selection valve i is formed by a 6-port 2-position switching valve.

In the above operation circuit, when operating the hydraulic hammer, the selection valve i is switched to the left operating position as shown in FIG. 2, and the hydraulic cylinder a side pipelines b and c are set to the downstream side of the direction switching valve h. By connecting and short-circuiting the conduits e and f on the hydraulic motor d side and switching the directional control valve h to the left or right operating position in this state, the pressure oil from the hydraulic source g is supplied to the hydraulic cylinder a. Then, the hydraulic cylinder a operates and the hydraulic hammer moves up and down.

When operating the hydraulic auger, the selection valve i is switched to connect the hydraulic motor d side conduits e and f to the downstream side of the direction switching valve h, and the hydraulic cylinder a side conduits b and c are short-circuited. In this state, by switching the directional control valve h to the left or right operating position, the pressure oil from the hydraulic source g is supplied to the hydraulic motor d, the hydraulic motor d operates, and the hydraulic auger rotates.

[Problems to be solved by the invention] However, in the operation circuit of the hydraulic hammer and the hydraulic auger, (i) since the 6-port 2-position switching valve is used as the selection valve, the number of pipelines connected to the selection valve is However, the number of pipelines becomes complicated, and the number of pipelines increases, which complicates the structure. (Ii) Since the selection valve has 6 ports, it is large and expensive, and a solenoid valve can be used. There is a problem such as poor workability because it cannot be done.

The present invention has been made in view of the above circumstances, and is intended to reduce the size of the device, simplify the work for connecting a pipeline, and improve workability.

[Means for Solving the Problems] In the present invention, a hydraulic motor for rotating a hydraulic auger and a direction switching valve for controlling a flow direction of oil supplied to the hydraulic motor are connected by two pipelines, and the pipelines are connected. One of the pipelines is provided with a selection valve consisting of a 3-port 2-position switching valve, and the opposite direction switching valve side of the selection valve is connected to a hydraulic cylinder oil chamber for lifting and lowering a hydraulic hammer whose volume increases when the hydraulic hammer rises. The hydraulic cylinder oil chamber for raising and lowering the hydraulic hammer whose volume increases when the hydraulic hammer descends is connected to the tank without the selection valve and the direction switching valve.

[Operation] When operating the hydraulic hammer, the oil from the hydraulic source
The selection valve and the direction switching valve are switched so that the oil is supplied to the hydraulic cylinder oil chamber that increases when the hydraulic hammer rises, whereby oil is supplied to the hydraulic cylinder and the oil discharged from the hydraulic cylinder is selected and the direction switching valve. It is returned to the tank without going through. When operating the hydraulic auger, the selection valve is switched so that the oil from the hydraulic source is supplied to the hydraulic motor, and the direction of the oil from the hydraulic source is changed by switching the direction switching valve. Reverses normally.

[Embodiment] An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the present invention.

The pipe lines 3 and 4 are connected to the direction switching valve 2 connected to the hydraulic power source 1, and the pipe line 3 is connected to the selection valve 5 composed of a 3-port 2-position switching valve. And the pipe lines 4 and 6 are connected to the hydraulic motor 8 for rotating the hydraulic auger.

The pipe line 10 of the hammer unit 9 is connected to the tip of the pipe line 7, and the pipe line 10 is connected to the head side oil chamber 13 of the hydraulic cylinder 12 via the switching valve 11 so that the switching valve 11 of the pipe line 10 and A pipeline 14 is connected between the hydraulic cylinders 12 so that oil can be returned from the pipeline 14 to the tank 15, and a pipeline 16 is provided upstream of the switching valve 11 of the pipeline 10.
To connect the pipe 16 to the rod-side oil chamber 17 of the hydraulic cylinder 12.
Connect to.

Pilot lines 17 and 18 are connected to the upstream side of the line 16 connecting portion of the line 10 and the line 14, the pilot lines 17 and 18 are connected to the directional switching valve 19, and the directional switching valve 19 and the switching valve are connected. 11 is connected by a pilot line 20.

When operating the hydraulic hammer, the selection valve 5 is switched so that the pipelines 3 and 7 communicate with each other, and the direction switching valve 2 is switched so that the pressure oil from the hydraulic pressure source 1 flows into the pipeline 3. Hydraulic cylinder
When the piston rod 14 is at the lower limit and the hydraulic hammer is lifted by ascending from this, the direction switching valve 19 is switched so that the pipe line 18 and the pilot pipe line 20 communicate with each other. Therefore, the switching valve 11 is switched so that the pressure oil is not sent to the head side oil chamber 13 of the hydraulic cylinder 12 as shown in FIG.

The pressure oil from the hydraulic pressure source 1 is supplied to the rod side oil chamber 17 of the hydraulic cylinder 12 through the direction switching valve 2, the pipe 3, the selection valve 5, the pipe 7, and the pipes 10 and 16, and the head side oil is supplied. Oil in chamber 13 is returned from line 14 to tank 15. Therefore, the piston rod of the hydraulic cylinder 12 rises.

When the hydraulic hammer is lifted at the upper limit position, a command is given to the direction switching valve 19 so that the pilot lines 17 and 20 are switched to communicate with each other. Therefore, the switching valve 11 is switched by the pressure oil from the hydraulic pressure source 1 so that the pressure oil is supplied from the conduit 10 to the head side oil chamber 13 of the hydraulic cylinder 12. For this reason, the same pressure per unit area acts on the upper and lower surfaces of the piston of the hydraulic cylinder 12, but since the upper surface of the piston has a larger pressure receiving area, in addition to its own weight such as a hydraulic hammer, pressure oil is used. The force acts downward, which causes the piston rod to descend and the hydraulic hammer to drop.

The pressure oil discharged from the rod-side oil chamber 17 of the hydraulic cylinder 12 to the pipeline 16 enters the pipeline 16 to the pipeline 10, merges with the pressure oil from the hydraulic source 1, passes through the switching valve 11, and passes through the hydraulic cylinder. It is circulated and supplied to 12 head-side oil chambers 13. A part of the pressure oil sent from the direction switching valve 11 to the head side oil chamber 13 is returned to the tank 15 from the pipe line 14.

Then, by repeating the above operation, the hydraulic hammer repeatedly rises and falls, and a pile is driven.

When the hydraulic hammer is dropped, surge pressure is generated in the pipe line 7 and the like, but since the pipe lines 6 and 4 are completely cut off from the pipe line 7, the surge pressure does not act on the hydraulic motor 8.

When operating the hydraulic auger, the selection valve 5 is switched so that the pipe lines 3 and 6 are in communication, and the direction switching valve 2 is switched from the position shown in FIG. 1 to the left and right. When the direction switching valve 2 is switched to the left in FIG. 1, pressure oil is supplied from the direction switching valve 2 and the conduit 4 to the hydraulic motor 8 to rotate the hydraulic motor 8 to select the conduit 6. It is returned to the tank 21 from the valve 5, the pipe line 3, and the direction switching valve 2. When the direction switching valve 2 is switched to the right in FIG. 1, the pressure oil reverses the above flow and the hydraulic motor 8 rotates in the reverse direction. The rotation of the hydraulic motor 8 rotates the hydraulic auger.

The operation circuit of the hydraulic hammer and the hydraulic auger of the present invention is not limited to the above-mentioned embodiment, and it goes without saying that various modifications can be made without departing from the scope of the present invention.

[Advantage of the Invention] As described above, according to the operation circuit of the hydraulic hammer and the hydraulic auger of the present invention, i) since the 3-port 2-position switching valve is used as the selection valve,
The number of pipelines connected to the selection valve is reduced, the pipeline connection work is facilitated, and the existing device can be easily modified.

ii) The number of pipelines connected to the selection valve is small, which simplifies the device structure. iii) Since the selection valve has 3 ports, it can be made small and inexpensive. iv) The selection valve can be a solenoid valve. Therefore, workability is good, v) surge pressure does not act on the hydraulic motor, safety is good, and various immediate rare effects can be achieved.

[Brief description of drawings]

FIG. 1 is an illustration of an embodiment of the present invention, and FIG. 2 is an illustration of a conventional example. In the figure, 1 is a hydraulic power source, 2 is a directional control valve, 3 and 4 are conduits, 5 is a selection valve, 6 and 7 are conduits, 8 is a hydraulic motor, and 10, 14 and 16 are conduits.

Claims (1)

[Scope of utility model registration request] 1. A hydraulic motor for rotating a hydraulic auger and a directional control valve for controlling a flow direction of oil supplied to the hydraulic motor.
Connected by a main line, and one of the lines is provided with a selection valve consisting of a 3-port 2-position switching valve, and the volume on the opposite direction switching valve side of the selection valve increases when the hydraulic hammer rises. It is characterized in that it is connected to a hydraulic cylinder oil chamber for lifting a hydraulic hammer, and a hydraulic cylinder oil chamber for lifting a hydraulic hammer whose volume increases when the hydraulic hammer descends is connected to a tank without passing through the selection valve and the direction switching valve. Hydraulic hammer and hydraulic auger operation circuit.