JPH0414504Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention is a pile press-in aid that presses the pile into the ground using the thrust generated by a chain installed along the leader and a sprocket that meshes with the chain. It is related to the device.

[Conventional technology]

As shown in FIG. 1, both ends of the chain 2 are fixed to the upper and lower ends of the leader 1, and a rotating device 6 for the casing 4 and the auger screw 5 is attached to the elevating body 3 that can move up and down along the leader 1. , the steel sheet pile is fixed to the outer surface of the casing 4 by the chuck 7, and the chain 2 is engaged with the driving sprocket 8 provided on the elevating body 3, and the auger screw 5 is vertically moved by the thrust generated by the rotation of the sprocket 8. A chain elevator type pile press-in device that presses a pile body into the ground while drilling a hole has been registered as a utility model by the applicant.
Already proposed by No. 1486918.

The above-mentioned chain elevator system does not require driving a chain unlike the loop chain system, so it has the advantage of having a simple structure, easy operation, and being able to obtain a strong pressing force.

[Problem that the invention attempts to solve]

By the way, when the driving sprocket 8 is rotated in the direction of the arrow in FIG. 1 to move the elevating body 3 upward,
The tension between the upper anchor 2a of the chain 2 and the lifting body 3 is tense, but the lower anchor 2
There will be slack between b and the lifting body 3, and it is necessary to automatically absorb this slack.

This idea was made in consideration of the above points, and it is a pile press-in auxiliary device that can automatically absorb the loosening of the chain that occurs when the elevating object is moved using the hydraulic pressure for driving the elevating object. The purpose is to provide.

[Means for solving problems]

In order to solve the above problems, this invention involves winding the lower folded part of the chain, which has both ends fixed to the upper and lower ends of the leader, around the sprocket of the tension cylinder attached to the lower part of the leader. A driving sprocket driven by a hydraulic motor is provided on the movable elevating body, and the chain is engaged with the sprocket so that the elevating body moves up and down with the rotation of the sprocket. and the pressure receiving chamber of the tension cylinder are connected via a throttle valve and a check valve connected in parallel to the throttle valve.

[Effect]

When pressure oil is supplied to the hydraulic motor that drives the drive sprocket of the elevating body in the direction of moving the elevating body upward, a portion of the pressure oil flows into the pressure receiving chamber of the tension cylinder and is inserted between the elevating body and the lower anchor. The slack in the chain that occurs is absorbed and tightened by stretching the tension cylinder.

When moving the elevating body downward, the control valve is closed and the tension cylinder is locked in the extended state to prevent the chain from loosening between the elevating body and the upper anchor.

〔Example〕

Hereinafter, embodiments of this invention will be described based on the accompanying drawings.

As shown, a tension cylinder 11 is attached to the lower part of the leader 1 with its piston rod 12 fixed to an anchor member 13, and a tension sprocket 15 is pivotally fixed to the lower end of the cylinder tube 14.

The lower part of the chain 2, whose upper end is fixed to the leader 1 at the upper anchor 2a, is folded upward at the lower part of the leader 1, and is attached to the anchor member 13 by the lower anchor 2b.
The bent portion of the chain 2 is wound around the tension sprocket 15.

As shown in FIG. 2, the relationship between the drive sprocket 8 of the elevating body 3 attached to the leader 1 and the chain 2 is as shown in FIG. , 17 to mesh with the drive sprocket 8, and rotation of the drive sprocket 8 by the hydraulic motor 18 produces a feeding action between the chain 2 and the elevating body 3 to move it up and down.

FIG. 3 shows the hydraulic circuit of the hydraulic motor 18 and the tension cylinder 11.
A passage 21 provided in the piston rod 12 connects a pressure oil pipe 19 that rotates the elevating body 8 in the direction of arrow A in which the elevating body 3 moves upward, and a pressure receiving chamber 20 of the tension cylinder 11.
A throttle valve 23 and a check valve 24 connected in parallel to the throttle valve 23 are installed in the middle of the pipeline 22, and the back pressure chamber 25 of the cylinder 11 is connected to the hydraulic fluid. It is connected to the supply tank T.

As shown in FIG. 4, the lower part 1a of the leader 1 is provided with a pivot pin 2 for a length sufficient to accommodate the elevating body 3.
When the pile body is press-fitted, the upper part 1b and lower part 1a of the leader 1 are connected with fixing bolts 27 as shown in FIG.
When the reader 1 is in a moving state lying horizontally, the 4th
As shown in the figure, uncouple the fixing bolt 27 and
a is bent, and the elevating body 3 positioned on this lower part 1a is moved downward to lower the height of the entire device so that movement is not restricted.

Incidentally, when bending the lower part 1a of the leader, the elevating body 3 and the lower part 1a are connected by a fixing bar 28.

The pile press-in device of this invention has the above-mentioned configuration, and in order to move the elevating body 3 upward with the leader 1 in an upright position as shown in FIG. 1, pressure oil is supplied from the piping 19 to the hydraulic motor 18. When the tension cylinder 11 is rotated in the direction of arrow A in FIG. 3, a part of the pressure oil flows into the pressure receiving chamber 20 of the tension cylinder 11 through the check valve 24.
By expanding this cylinder 11, slack in the chain 2 generated between the elevating body 3 and the lower anchor 2b is absorbed.

Next, when press-fitting the pile to move the elevating body 3 downward, the throttle valve 2 is
3 and locking the cylinder 11, the tension of the chain 2 between the elevating body 3 and the lower anchor 2b is supported by the cylinder 11 via the sprocket 15.

In addition, when the leader 1 is horizontally laid down, the lower part 1a
To fold the lower part 1a, after fixing the elevating body 3 and the lower part 1a with the fixing bar 28, the fixing bolt 27 is released and the throttle valve 23 is fully opened with the lower part 1a being able to be folded.

When pressure oil is supplied to the hydraulic motor 18 from the piping 29, it rotates in the direction opposite to arrow A in FIG. 3, and at this time,
The chain 2 between the lifting body 3 and the upper anchor 2a uses the pin 26 as a fulcrum and tries to bend by rotating counterclockwise in FIG. The tension moves in the chain 2 between it and the anchor 2b, the tension cylinder 11 is compressed, and the oil in the pressure receiving chamber 20 is guided to the piping 19 through the throttle valve 23, and the oil is transferred from the tank into the back pressure chamber 25. Oil is supplied, and as shown in FIG. 4, the upper part 1b of the leader is laid down horizontally, and the lower part 1a, where the elevating body 3 is located, is bent.

〔effect〕

As described above, according to this invention, the lower part of the chain is wound around the sprocket of the tension cylinder attached to the leader, and the hydraulic motor and tension cylinder that move the elevating body up and down are connected to the throttle valve and check valve. Since they are interlocked through the chain elevator system, the power used for driving can be used as the power for the chain tightener when the lifting body moves up and down using the chain elevator system.
Automatic absorption of chain slack and chain tensioning can be configured extremely easily.

Furthermore, if a high-pressure type tension cylinder is used, the thrust force can be designed to be higher than the circuit pressure, and the piping relationship can be made compact.

[Brief explanation of the drawing]

Figure 1 is a front view of the pile press-in auxiliary device according to this invention, Figure 2 is an explanatory diagram showing the relationship between the elevating body and the tension cylinder in the above, Figure 3 is an enlarged explanatory diagram of the main parts of the same, and Figure 4 is a front view when the leader is folded. 1 is a leader, 2 is a chain, 3 is an elevating body, 8 is a drive sprocket, 11 is a tension cylinder, 1
5 is a tension sprocket, 18 is a hydraulic motor, 20 is a pressure receiving chamber, 23 is a throttle valve, and 24 is a check valve.

Claims (1)

[Scope of utility model registration request] The lower folded part of the chain, which has both ends fixed to the upper and lower ends of the leader, is wound around the sprocket of a tension cylinder attached to the lower part of the leader, and is driven by a hydraulic motor to an elevating body attached to the leader so that it can move up and down. A drive sprocket is provided, and the chain is engaged with the sprocket so that the elevating body moves up and down by rotation of the sprocket, and one oil supply path of the hydraulic motor and the pressure receiving chamber of the tension cylinder are connected to the throttle valve and in parallel thereto. Pile press-in auxiliary device connected via a check valve connected to.