JP2000144732A - Working bench rising and falling device of pile driver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a working bench to a leader in a liftable manner without relying on a wire rope in a pile driver providing ribs for reinforcing the leader to the side of the leader in the vertical direction at a specific interval and to make it possible to prevent the falling of the working bench. SOLUTION: A guide rail over the overall length of a leader and a rack 21 are formed in the side of the leader 24 of a pile driver, and a working bench 20 is interlocked with the guide rail in a liftable manner. Then, a hydraulic motor 30 having a pinion 32 rotating by interlocking with the rack is provided in the working bench and, at the same time, a claw 35 is provided between ribs 13 and 13 on the side of the leader in an insertable manner. A hydraulic cylinder 37 separating a spring 36 from the claw 35 is provided in the claw 35, a motor operation hydraulic circuit 38 is mounted on the hydraulic motor, and when the hydraulic motor 30 is switched to a neutral position from a forward or a reverse position, load pressure in the hydraulic cylinder 37 is exhausted to a drain 46 to connect with a cylinder operation hydraulic circuit 55 inserting the claw 35 between the ribs by accumulated elastic spring force of the spring 36.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pile driving machine, and more particularly to a pile driving machine in which a work table used for auxiliary work can be attached to a leader of the pile driving machine without dropping. The present invention relates to a platform elevating device.

[0002]

2. Description of the Related Art FIGS. 5 and 6 show a working machine of this kind, a pile driving machine and a pile driving machine as an auxiliary device. As shown in FIG. 5, in the pile driving machine 1, an auger 16 is
A leader 3 is erected to support a working device such as a hammer and a pile so as to be able to move up and down, and a back stay 4 is provided at the rear of the vehicle body 2 to support the leader 3 from behind. A sheave 10 for guiding the wire rope 5 is supported on the upper part of the vehicle body 2 or the leader 3, and the wire rope 5 unreeled from a winch (not shown) mounted on the vehicle body 2 is placed above the sheave 10. And is connected to the working device which moves up and down along the front surface of the reader.

Further, as shown in FIG. 5, a work table elevating winch 7 is provided on the reader 3 separately from the winch (not shown), and a work table 8 is provided on a side surface of the reader 3.
Is mounted so as to be able to move up and down freely,
The wire rope 9 is guided downward in the direction of gravity by the guidance of a sheave 6 that is pivotally supported on the top of the reader 3 or the like, and the distal end of the wire rope 9 is connected to the worktable 8. Therefore, in the conventional pile driving machine 1, the worktable 8 can be stopped at a predetermined work position by the forward / reverse rotation of the worktable elevating winch 7.

[0004] Incidentally, the auxiliary work performed on the work table 8 includes attaching, detaching, repairing and checking the working device such as the auger and hammer, or adding a rod or a screw when using the auger, and further grounding. There is guidance of the casing or pile to the auger or hammer axis.

[0005] As shown in FIG. 6, in the pile driving machine 1, the tip of the wire rope 9 is connected to one end of a claw 11 pivotally supported by the worktable 8 in order to prepare for a fall accident of the worktable 8. It is connected to the unit 12. The claw 11 is rotatable around a horizontal axis around a support shaft 12 fixed to the work table 8, and when the wire rope 9 is not tensioned by cutting the wire rope 9 or the like, the work table 8 is rotated. When it is rotated clockwise by the urging force of the return spring 15 which is stretched between the claw 11 and one end 14a of the claw 11, the claw 11 is interposed between the ribs 13 fixed to the side surface of the reader 3.
The other end 14b of the rib 1 is inserted to restrict the lowering of the worktable 8, and when the wire rope 9 is turned counterclockwise against the urging force of the return spring 15 by the tension of the wire rope 9, the rib 1
The other end portion 14b of the claw 11 is pulled out from between the portions 3 and 13, so that it can be moved up and down.

[0006]

For this reason, it is possible to prevent the work table 8 from dropping due to the wire rope 9 being dropped due to cutting or the sudden loosening of the wire rope 9 due to vibration or the like.

However, in order to move the worktable 8 up and down along the side surface of the reader 3, the vehicle body 2 and the reader 3
And the arrangement of the wire rope 9 is complicated, and a large amount of work time has to be spent for hanging the work table 8 and the wire rope 9 as auxiliary equipment.

Therefore, a technical problem to be solved arises in order to allow the work table to be lifted and lowered by the reader without using the wire rope and to prevent the work table from dropping. The purpose is to solve.

[0009]

SUMMARY OF THE INVENTION The present invention has been proposed in order to achieve the above-mentioned object. The present invention reinforces a leader on a side surface of a leader for supporting a working device such as an auger, a hammer and a pile so as to be able to move up and down. In a pile driving machine in which ribs are fixed at predetermined intervals in the vertical direction, a guide rail and a rack are formed on the side surface of the leader over the entire length of the leader,
The worktable is engaged with the guide rail so as to be able to move up and down freely,
A hydraulic motor having a pinion that meshes with the rack and rotates is fixed to the work table, and a claw is provided on the side surface of the reader so as to be freely inserted and removed between the ribs. A spring for urging and inserting the spring; and a hydraulic cylinder for releasing the pawl from between the ribs against the elastic force of the spring. A motor operating hydraulic circuit is attached to the hydraulic motor, and the motor operating In the hydraulic circuit, when the motor operating hydraulic circuit switches the motor from the neutral position to the normal rotation or reverse rotation position, the load pressure of the motor operating hydraulic circuit is supplied to the cylinder to release the pawl from between the ribs. When switching from the forward rotation or reverse rotation position to the neutral position, the load pressure is discharged from the hydraulic cylinder to the drain, and the spring force accumulated by the spring causes a front space between the ribs. Provided is a workbench elevating device for a pile driving machine to which a cylinder operating hydraulic circuit for inserting a claw is connected, and further, a communication passage for connecting the cylinder operating hydraulic circuit to a motor suction side and a discharge side of the motor operating hydraulic circuit. A valve for connecting the load take-out passage communicating with an outlet of a shuttle valve provided in the communication passage, the drain and a cylinder chamber of the hydraulic cylinder, and the motor operating hydraulic circuit When the motor is switched from the neutral position to the forward or reverse position, the load take-out path is communicated with the hydraulic cylinder, and when the motor is switched from the forward or reverse position to the neutral position by the motor operating hydraulic circuit, An object of the present invention is to provide a workbench lifting and lowering device for a pile driver, comprising: a valve that communicates the load takeout path with both the hydraulic cylinder and the drain.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to FIGS. The same components as in the prior art are denoted by the same reference numerals, and description thereof will be omitted.

FIGS. 1 and 2 show a pile driving machine in which a guide rail and a rack for moving a work table up and down on a leader are integrally provided.

As shown in FIG. 1 and FIG.
In the present embodiment, a pair of pin brackets 22, 22 extending over the entire length of the reader 21 is used as a rack body, and the pair of pin brackets 22, 22 are spaced apart by a predetermined distance in the longitudinal direction by a large number of pins 23. The pair of pin brackets 22 are fixed to the side surface of the reader 24 by welding or the like to be integrated. For mounting the pins 23, for example, a pin insertion hole (not shown) is formed at a predetermined interval from one end of the pair of pin brackets 22, 22 with the other end facing the other end. After the pins 23 are respectively inserted into the pins 23, the ends of the pins 23 and the pin brackets 22 are welded. Then, guide rails 25, 25 bent outward at substantially right angles are formed over the entire lengths at the distal ends of the pair of pin brackets 22, 22, and further surround the guide rails 25, 25 from outside. And a fall prevention tool 2 having an L-shaped cross section that slides with the back surfaces of the guide rails 25 and 25 as sliding surfaces.
6 and 26 are fixedly mounted at substantially the center of one side of the work table 20,
The overturn prevention tools 26, 26 are connected to the guide rails 25, 2
By fitting to one end or the other end of 5,
The work table 20 is attached to the reader 21 so as to be detachable and vertically movable.

Further, in order to allow the work table 20 to move up and down smoothly, the reader 2
4 are fixed to the tips of both ends of the ribs 13 projecting outward from the side surface of the leader 24, and guide rollers 29, 29 ... Are configured to engage with the guide pipes 27 and roll.

Accordingly, in this configuration, the guide rollers 29, 29 are engaged with the pair of guide pipes 27, and are rolled, so that the work table 20 can be easily moved up and down and detached. .

A hydraulic motor 30 is provided below the work table 20.
A pinion 32 or a sprocket that meshes with the rack 21 is integrally attached to a motor shaft 31 of the hydraulic motor 30. The hydraulic motor 30 is fixedly mounted on the work table 20 so that the pinion 32 or sprocket meshes with the rack 21, specifically, the pins 23, and rotates.

Therefore, if the hydraulic motor is rotated forward and backward, the work table 20 can be smoothly moved up and down along the pair of guide rails 25, 25 and the pair of guide pipes 27, 27. Also, as shown in FIG.
The work table 20 has a support shaft 1 fixed to the work table 20.
The work table 2 is inserted into ribs 13 that reinforce the side surface of the reader 24 with the pivot 2 as a fulcrum.
The pawl 35 is rotatably supported so as to restrict the vertical movement of zero.

When the claw 35 is rotated clockwise by the elastic force of a return spring 36 (elastic means) interposed between its one end 33 and the work table 20, one end thereof is rotated. 33 is inserted between the ribs 13 and 13 of the leader 24 to restrict the lowering of the worktable 20, and a hydraulic cylinder 37 connecting the other end 34 of the claw 35 and the worktable 20 is provided by the return spring. When the work table 20 is extended against the elastic force of 36, it is separated from the ribs 13 to allow the work table 20 to move up and down.

FIG. 3 shows a hydraulic circuit in which a cylinder operating hydraulic circuit 55 for operating the hydraulic cylinder 37 is connected to a motor operating hydraulic circuit 38 for driving the hydraulic motor 30. The motor operating hydraulic circuit 38 By switching the first switching valve 40 comprising a three-chamber, four-port electromagnetic switching valve, a pair of pipelines 43, 44 communicating with one supply / discharge port 41 and the other supply / discharge port 42 of the hydraulic motor 30 is hydraulically driven. The pump 45 and the drain 46 are switched and connected to each other. The hydraulic cylinder 37 is expanded and contracted by a cylinder operating hydraulic circuit 55, and the claw 35 is operated to control the elevation of the work table 20. Make up.

That is, the front and rear of the hydraulic motor 30 are communicated through a communication passage 47, and a load take-out passage 49 connected to an outlet of a shuttle valve 48 provided in the communication passage 47 is drained through a second switching valve 50. 46 and the cylinder chamber 51 of the hydraulic cylinder 37. When the first switching valve 40 is switched from the neutral position to the forward rotation or the reverse rotation position, the second switching valve 50 is switched from the second switching position to the first switching position, and the load take-out path 49 is switched to the first switching position. When the first switching valve 40 is switched from the forward rotation or the reverse rotation position to the neutral position, the first switching valve is switched from the first switching position to the second switching position to communicate with only the cylinder chamber 51 of the hydraulic cylinder 37, and the load removal is performed. The passage 49 is configured to communicate with the cylinder chamber 51 of the hydraulic cylinder 37 and the drain 46.

In this case, the hydraulic cylinder 3
7 is connected to the motor operating hydraulic circuit 38 supplied to the cylinder chamber 51 through the load take-out passage 49.
When the load pressure is a predetermined load pressure PM, the cylinder rod 52 is actuated to the extension side against the elastic force of the return spring 36, and as a result of the operation to the extension side, the claw 35 is moved to the leader 24. The pressure receiving area is set so as to separate from the side ribs 13.

As described above, the communication path 47 and the shuttle valve 4
8, the load taking-out passage 49 and the second switching valve 50 constitute a cylinder operating hydraulic circuit 55, and the second switching valve 50 interlocked with the switching of the first switching valve 40 allows the ribs 13 and
The engagement and disengagement of the claw 35 with respect to the thirteen can be performed, and the engagement, disengagement of the claw 35 can control lifting, stopping, and lowering of the work table 20.

Next, the operation of the present embodiment will be described.

As shown in FIG. 3, when the first switching valve 40 is switched to the neutral position and the second switching valve 50 is switched to the second switching position, the hydraulic pump 45
Communicates with the drain 46, and the load take-out path 49
And the cylinder chamber 51 of the hydraulic cylinder 37. For this reason, the claw 35 is inserted between the ribs 13 and 13 of the leader 24 by the elastic force of the return spring 36, and the vertical movement of the work table 20 is restricted by the insertion of the claw 35.

When performing an auxiliary work using the work table 20, an operator on the work table 20 sends an instruction to an operator of the vehicle body. When the operator on the work table 20 instructs the work table 20 to be raised, the operator switches the operation lever from the neutral position to the raised position. By this switching, FIG.
As shown in FIG. 5, one solenoid 40A of the first switching valve 40 and the solenoid 50A of the second switching valve 50 are excited, and the first switching valve 40 is switched from the neutral position to the forward rotation position, and the second switching valve 50 Switches from the second switching position to the first switching position. As a result, the discharge port of the hydraulic pump 45 and the one supply / discharge port 41 of the hydraulic motor 30 communicate with each other,
The second supply / discharge port 42 of the hydraulic motor 30 communicates with the drain 46, and the load pressure extraction passage 49 communicates only with the cylinder chamber 51 of the hydraulic cylinder 37. Since the load pressure take-out passage 49 communicates only with the cylinder chamber 51 of the hydraulic cylinder 37 and cuts off the communication with the drain 46, the load pressure of the motor operating hydraulic circuit 38 is directly applied to the cylinder chamber 5.
Acts on 1.

Thereafter, when the load pressure of the motor operating hydraulic circuit 38 reaches a predetermined pressure PM, that is, a pressure at which the work table 20 can be raised and lowered, the shuttle valve 48 selects the load pressure selecting function of the motor operating hydraulic circuit 38. Load pressure PM acts on the cylinder chamber 51 of the hydraulic cylinder 37.

As described above, the pressure receiving area of the cylinder rod 52 of the hydraulic cylinder 37 is determined by the return spring 36 when the load pressure PM acts on the cylinder chamber 51.
The cylinder rod 52 is moved to the extension side against the resilience of the above, and by this extension, the claw 35 is set to rotate counterclockwise around the support shaft 12 as the rotation center.
For this reason, when the load pressure of the motor operating hydraulic circuit 38 reaches the predetermined load pressure PM, the claw 35 is pulled out from between the ribs 13 on the side surface of the reader 24, and the lifting regulation of the work table 20 is released. Therefore, the workbench 20 has the motor shaft 3
It rises in accordance with the rotation of the pinion 32 or the sprocket that rotates together with 1.

After the work table 20 is raised, if the operator instructs to stop, the operator returns the operation lever from the raised position to the neutral position. As a result, the first switching valve 40 forms an electric circuit so as to return with the spring of the other solenoid 40B, and at the same time, the solenoid 50A of the second switching valve 50
An electric circuit is constructed so as to release the power supply to the power supply. Therefore, the first switching valve 40 is switched from the forward rotation position to the neutral position,
The switching valve 50 is set in the first position by the elastic force of the spring 50B.
The position is switched from the switching position to the second switching position, and the load outlet passage 49 communicates with both the cylinder chamber 51 of the hydraulic cylinder 37 and the drain 46. As a result, the cylinder rod 52 of the hydraulic cylinder 37 is
6 is pushed back to the contraction side by the elastic force of the cylinder chamber 5.
The hydraulic oil in 1 is discharged to the drain 46.

Accordingly, the pawl 35 is inserted between the ribs 13 of the reader 24, and the work table 20 stops. Of course, since the claw 35 is inserted between the ribs 13, 13, the work table 20 is prevented from falling.

When a predetermined auxiliary operation is completed on the work table 20 and the operator instructs the operator to lower the operation lever, the operator switches the operation lever to move the first switching valve 40 from the neutral position to the reverse position. Switch. As a result, the solenoid 40B of the first switching valve 40 is excited,
The solenoid 50A of the switching valve 50 is excited, the first switching valve 40 is at the lower position from the neutral position, and the second switching valve 50 is at the second position.
The position is switched from the switching position to the first switching position, and as a result, a load pressure acts on the cylinder chamber 51 of the hydraulic cylinder 37. Of course, the discharge port of the hydraulic pump 45 communicates with the other supply / discharge port 42, communicates with the first supply / discharge port 41, and the drain 46, and the motor 30 rotates in the reverse direction. When the load pressure of the motor operating hydraulic circuit 38 reaches the predetermined pressure PM, as in the case of the forward rotation, the cylinder rod 5
2 moves to the extension side, and the claw 35 rotates counterclockwise against the elastic force of the return spring 36 and separates from the ribs 13 of the leader 24. Therefore, the stop of the work table 20 is released, and the work table 20 descends toward the ground. At this time, the cabin operator is
The work table 20 is stopped by monitoring the lowering of 0 and lowering the operating lever to a predetermined height when the operating lever is lowered to a predetermined height.

When the work table 20 is raised, stopped, or lowered,
In the event that the pinion 32 or the sprocket is chipped or the pin 23 is sheared, the pressure of the motor operating hydraulic circuit 38 becomes lower than the predetermined pressure PM. For this reason, the resilient force of the return spring 36
Is automatically inserted between the ribs 13 of the reader 24 to prevent the workbench 20 from dropping. Of course, when an emergency stop is desired due to a danger signal, the second switching valve 50
A switch (not shown) for cutting off the current supply is provided in a line for supplying the current to the solenoid 50A of this type, and this switch is disposed on the work table 20.
Emergency stop is also possible.

As described above, the workbench lifting and lowering device of the pile driver according to the present embodiment allows the claw 35 to be moved to the leader 24 based on the load pressure of the motor operating hydraulic circuit 38 for raising and lowering the workbench 20. Since it is inserted between the ribs 13, 13, it is possible to move up and down safely and reliably, and to ensure safety without using a sensor such as a pressure switch. A pressure switch or a pressure sensor such as a pressure sensor is interposed in the operation circuit 38, and when the motor operation circuit 38 reaches the predetermined pressure PM, the first switching valve 4 is operated by a controller or a sequencer.
0, the switching of the second switching valve 50 may be controlled. Also, a shaft torque sensor is provided on the motor 30, and the shaft torque when the work table 20 is moved up and down is detected by the torque sensor in advance. The breakage of the pinion 32 or the like may be detected by detecting the value and the actual torque at the time of actual ascending and descending, and the first switching valve 40 and the second switching valve 40 may be detected in accordance with the detection result. The switching of the switching valve 50 may be controlled.

In this embodiment, the rack 2
1. Hydraulic motor 30, motor operating hydraulic circuit 38, cylinder operating hydraulic circuit, claw 35, return spring 3
6 and the like, the lifting and lowering of the work table 20 is controlled and the fall is restricted, but the rack and pinion is abolished,
Connecting the hydraulic motor 30 to a winch (not shown),
The winch is mounted on the vehicle body 2, a wire rope of the winch is connected to the work table 20, and the winch is rotated forward, backward, or stopped while the wire rope is guided by a sheave. It is also possible to go up and down.

The present invention can be variously modified without altering the spirit of the present invention, and the present invention naturally extends to the modified ones.

[0034]

According to the present invention, as described in detail in the above embodiment, a guide rail and a rack are formed on the side surface of the reader so as to extend over the entire length of the reader, and the work table can be freely moved up and down on the guide rail. Combine. Therefore, it is possible to easily attach and detach the work table to and from the pile driver. Also, a hydraulic motor having a pinion or a sprocket that meshes with the rack is provided on the work table to enable the work table to be moved up and down. A spring means for constantly urging the claws in the insertion direction to insert them between the ribs, and a hydraulic cylinder for releasing the claws from between the ribs against the urging force of the spring means. Provided to prevent the lifting platform from dropping by the pawl, and a motor operating hydraulic circuit is attached to the hydraulic motor,
When the hydraulic motor is switched from the neutral position to the forward rotation or the reverse rotation position by the motor operation hydraulic circuit, the load pressure of the motor operation hydraulic circuit is supplied to the motor operation hydraulic circuit. When the hook is disengaged from between the ribs and the hydraulic motor is switched from the forward rotation or the reverse rotation position to the neutral position, the load pressure in the hydraulic cylinder is discharged to the drain, and the stored elasticity of the elasticity means is increased. Since the cylinder operating hydraulic circuit for inserting the claw between the ribs by force is connected, the work table can be raised and lowered and prevented from falling without using a special detecting means such as a pressure sensor. It is an invention that exhibits a remarkable effect.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention and is a plan view of a pile driver.

FIG. 2 shows an embodiment of the present invention and is a front view of a pile driver.

FIG. 3 is a circuit diagram showing a motor operating hydraulic circuit and a claw operating hydraulic circuit, showing an embodiment of the present invention, and showing a state where the circuits are switched to a stop position of a worktable;

FIG. 4 is a circuit diagram showing an embodiment of the present invention, showing a motor operating hydraulic circuit and a claw operating hydraulic circuit, and showing a state in which the circuit is switched to a raised position of a worktable.

FIG. 5 is a side view showing a conventional pile driver.

FIG. 6 is a detailed side view of a main part showing a work table equipped on a conventional pile driver and a fall prevention device for the work table.

[Description of Signs] 13 Rib 20 Work table 21 Rack 24 Leader 25 Guide rail 30 Hydraulic motor 32 Pinion 35 Claw 36 Spring 37 Hydraulic cylinder 38 Motor operating hydraulic circuit 55 Cylinder operating hydraulic circuit

Claims (2)

[Claims] 1. A pile driver in which working devices such as augers and hammers and ribs for reinforcing the leader are fixedly provided on a side surface of the leader for vertically supporting the pile at predetermined intervals in the vertical direction. A guide rail and a rack are formed on the side surface of the leader and extend over the entire length of the leader. A work table is engaged with the guide rail so as to be able to move up and down, and the work table has a pinion that meshes with the rack and rotates. A hydraulic motor is fixedly provided, and a claw is provided on the side surface of the leader so as to be freely inserted and removed between the ribs. A hydraulic cylinder is provided for releasing the pawl from between the ribs against a force, and a motor operating hydraulic circuit is attached to the hydraulic motor, and the motor operating hydraulic circuit is connected to the motor operating hydraulic circuit. When switching from the standing position to the forward rotation or the reverse rotation position, when the load pressure of the motor operating hydraulic circuit is supplied to the cylinder to release the claw from between the ribs, and when switching from the forward or reverse rotation position to the neutral position. ,
A work table for a pile driver, wherein a cylinder operating hydraulic circuit for discharging the load pressure in the hydraulic cylinder to a drain and inserting the pawl between the ribs by the spring force accumulated by the spring is connected. lift device. 2. A communication passage for communicating a motor suction side and a discharge side of the motor operation hydraulic circuit with the cylinder operating hydraulic circuit, and a load take-out path communicating with an outlet of a shuttle valve provided in the communication passage. And a valve for connecting a drain and a cylinder chamber of the hydraulic cylinder, wherein when the motor is switched from a neutral position to a forward rotation or a reverse rotation position by the motor operating hydraulic circuit, a load take-out path is provided to the hydraulic cylinder. And a valve for communicating the load take-out path to both the hydraulic cylinder and the drain when the motor is switched from the forward rotation position or the reverse rotation position to the neutral position by the motor operating hydraulic circuit. Item 2. A worktable elevating device for a pile driver according to Item 1.