JPH10148083A - Chuck device for boring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve workability at the time of rod extension works and rod stability and straight-ahead driving at the time of boring drilling. SOLUTION: A cylinder 22 is unified concentrically at the lower end section of a drive rod 17, a chuck piston 25 is installed slidably into the cylinder 22, and a plurality of chuck jaws 27 are mounted movably in the radial direction in the chuck piston 25. An outer sleeve 31 is fitted rotatably on the outer circumferential section of the cylinder 22, and a working-pressure supply means 41 is set up to the chuck piston 25 from the outer circumferential surface of the outer sleeve 31. The chuck piston 25 is supplied with working pressure, a drill rod R for boring inserted to the drive rod 17 is gripped by the chuck jaws 27, and the revolving torque and force in the vertical direction of the drive rod 17 are transmitted to the drill rod R. Working pressure fed to the chuck piston 25 is held by a check valve 52 fitted into the cylinder 22, and released by a check-release piston 63.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boring chuck device for gripping a boring rod and applying a rotational force and a vertical force to the rod.

[0002]

2. Description of the Related Art As disclosed in Japanese Patent Application Laid-Open No. 8-232572, a boring hollow rod (drill rod) inserted into a cylindrical drive shaft (drive rod) is gripped to rotate the drive rod. In some cases, a boring chuck device for transmitting a pushing force or a pushing force to a drill rod is provided inside a connection portion (crosshead) with a rod pushing hydraulic cylinder located at an upper end portion of a drive rod.

[0003]

In the chuck device described in this publication, the upper end insertion opening of the drive rod can be set at a relatively low position as compared with the chuck device before that, but since it is located at the upper end portion of the drive rod, However, there is a limit in reducing the overall height of the boring machine, and further improvement is required to make the drill rod extension work easier.

Further, in the chuck device described in this publication, since the upper end of the drive rod is gripped by the upper end of the drive rod, vibration of the drill rod and bending of a boring hole are likely to occur.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a chuck device capable of improving workability at the time of rod extension work, rod stability at the time of boring drilling, and straightness. Things.

[0006]

The invention described in claim 1 is mounted on a cylindrical drive shaft body to which a rotational force and a vertical force are applied while a boring rod is inserted. A boring chuck device, comprising a cylinder concentrically integrated with a lower end of a drive shaft, a chuck piston slidably provided in the cylinder, and a rod pressed radially inward by the chuck piston. A boring chuck device including a gripper and an operating pressure supply unit for supplying an operating pressure to a chuck piston.

[0007] A cylinder is provided at the lower end of the drive shaft so as to keep the overall height low, thereby improving the workability at the time of rod extension work, the rod stability at the time of boring drilling, and the like. A cylinder is provided integrally with the drive shaft to reduce the number of parts.

According to a second aspect of the present invention, there is provided the boring chuck device according to the first aspect, further comprising an outer cylinder rotatably fitted on an outer peripheral portion of the cylinder.

Then, the cylinder that rotates together with the drive shaft is covered with an outer cylinder.

According to a third aspect of the present invention, there is provided the boring chuck device according to the second aspect, wherein an operating pressure supply port provided on an outer peripheral surface of the outer cylinder, an outer peripheral surface of the cylinder and an inner cylinder. An annular communication groove provided between the outer peripheral surface of the cylinder and the inner peripheral surface of the outer cylinder along the communication groove; And a check valve provided inside the cylinder and holding a working pressure supplied to the chuck piston through the communication groove.

Then, the operating pressure is supplied from the operating pressure supply port of the outer cylinder through the communication groove between the cylinder and the outer cylinder into the cylinder, and the operating pressure is supplied to the chuck piston through the check valve in the cylinder. Is supplied, and the rod-holding body is pressed inward in the radial direction by the chuck piston, thereby integrally holding the boring rod and transmitting the rotational force and the vertical force to the rod. The check valve holds the working pressure once supplied to the chuck piston, so when the cylinder is rotating, release the working pressure supply to the working pressure supply port,
The pressure acting on the rotary seal between the outer peripheral surface of the cylinder and the inner peripheral surface of the outer cylinder can be reduced to reduce wear of the rotary seal.

According to a fourth aspect of the present invention, there is provided the boring chuck device according to the third aspect, further comprising a check release piston provided to be able to move forward and backward with respect to the check valve.

When releasing the rod gripping by the rod gripper, the check valve is pushed open by the check release piston, and the operating pressure on the chuck piston held by the check valve is released.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIG.

FIG. 2 shows a driving device for gripping a boring drill rod and forcibly rotating and vertically driving the drilling rod. A driving unit main body 12 is provided on a base 11. A rotation transmission device 13 is provided at an upper portion of the rotation transmission device 13. A pair of hydraulic cylinders 14 are attached to left and right portions of the rotation transmission device 13, An upper end portion of a drive rod 17 as a cylindrical drive shaft body is rotatably connected through the drive rod 17.

The drive rod 17 is connected to the rotation transmitting device 13
The chuck device 18 according to the present invention is mounted on the lower end of the drive rod 17.
A bellows 19 is provided between the rotation transmitting device 13 and the chuck device 18.
Is provided.

Drive rod 17 and chuck device 18
Is formed in a cylindrical shape so that a drill rod for boring (not shown) can be inserted from above to below, and while receiving a rotational force from the rotation transmitting device 13 in a state where the drill rod is inserted, A pressing force or a lifting force is applied from the cylinder 14.

As shown in FIG. 1, the chuck device 18
A cylinder 22 is concentrically integrated by screwing through a chuck body 21 screwed to the lower end of the drive rod 17, and a hollow chuck piston 25 is inserted into the cylinder 22 through O-rings 23 and 24. Are fitted concentrically slidably in the axial direction.

The inner tapered surface 26 of the chuck piston 25
A plurality of chuck jaws 27 as rod grippers which are pressed inward in the radial direction by the chuck piston 25 are movably fitted in the radial direction.

Further, the cylinder 22 is formed in multiple stages so that the inner peripheral surface becomes thicker toward the lower side with respect to the straight outer peripheral surface, and the inner cylindrical portion 28 is screwed on the lower inner peripheral surface of the cylinder 22. It is integrated.

An outer sleeve 31 as an outer cylinder is fitted on the outer peripheral surfaces of the cylinder 22 and the inner cylinder 28 from below.
For the cylinder 22 and the inner cylinder 28, the upper bush 32,
The outer sleeve 31 is rotatably fitted via a lower bearing 33 and an oil seal.

A lower portion of the chuck piston 25 is fitted to an upper portion of the inner cylindrical portion 28 so as to be slidable in the axial direction. The lower part of the bellows 19 is connected to the upper part of the outer sleeve 31.

The chuck piston 25 for generating a gripping force is pressed downward by a return spring 36 fitted in an annular groove 35 of the chuck body 21.
A compression coil spring 37 is fitted between the members 27, and each chuck jaw 27 is urged in the radially expanding direction.

Operating pressure (hydraulic pressure) for chuck piston 25
Is provided. The operating pressure supply means 41 is provided with an operating pressure supply port 42 on the outer peripheral surface of the outer sleeve 31, and a hole 43 between the outer peripheral surface of the cylinder 22 and the inner peripheral surface of the outer sleeve 31. Is provided with an annular communication groove 44 communicating with the outer peripheral surface of the cylinder 22 and the inner peripheral surface of the outer sleeve 31 along the upper and lower side edges of the communication groove 44. O-rings 45 and 46 are fitted.

The communication groove 44 communicates with a check valve 52 provided inside the cylinder 22 through a hole 51, and is formed between the cylinder 22 and the chuck piston 25 by the hole 53 passing through the check valve 52. The working pressure chamber 54 communicates with the working pressure chamber 54.

The check valve 52 is connected to a communication groove 44 from the working pressure supply port 42.
And retains the operating pressure supplied to the operating pressure chamber 54 of the chuck piston 25 via the sheet 55. The sheet 55 fitted in the inner hole of the cylinder 22 and the sheet 55 are provided so as to be able to freely contact and separate from the upper side of the sheet 55. Poppet valve 56 and this poppet valve 56 is seat 55
Compression spring 57 biasing the
It is formed by a plug 58 that locks the upper end of 57.

The pusher valve 56 of the check valve 52 is opposed to a tip pressing element 64 of a check release piston 63 which is fitted in an inner hole 61 of the cylinder 22 through an O-ring 62 in a liquid-tight manner. The lower part of the check release piston 63 is locked by a plug 65 screwed into the inner hole 61 of the cylinder 22. In the cylinder 22, a balance hole 66 is provided at a symmetric position of the inner hole 61 with respect to the center.

A pilot pressure supply port 71 for releasing a check is provided on the outer peripheral surface of the outer sleeve 31.
Between the outer peripheral surface of the outer sleeve 31 and the inner peripheral surface of the outer sleeve 31, an annular communication groove 73 communicated with the pilot pressure supply port 71 through a hole 72.
O-rings 46, 74 for maintaining liquid tightness between the outer peripheral surface of the cylinder 22 and the inner peripheral surface of the outer sleeve 31 are fitted on both upper and lower sides of the communication groove 73. The communication groove 73 has a hole 75
Through a pilot pressure chamber 76 provided below the check release piston 63.

Next, the operation of this embodiment will be described.

When an operating pressure (oil pressure) is supplied to the operating pressure supply port 42 of the outer sleeve 31 from a hydraulic pump (not shown) through a hydraulic valve and a hydraulic pipe, the operating pressure supply port
An operating pressure (oil pressure) is supplied from 42 to a check valve 52 in the cylinder 22 through a communication groove 44 and the like, and an operating pressure is further supplied to an operating pressure chamber 54 of the chuck piston 25 through the check valve 52. The operating pressure causes the chuck piston 25 to be pushed upward against the spring 36.

When the chuck piston 25 is raised, the chuck jaw 27 is pushed radially inward through the inner tapered surface 26, and the plurality of chuck jaws 27 integrally connect the boring drill rod R inserted through the drive rod 17. To transmit the rotational force and the pushing force or the pushing force to the drill rod R.

Even if the supply of the operating pressure to the operating pressure supply port 42 is stopped or released, the poppet valve 56 which is in close contact with the seat 55 of the check valve 52 operates the operating pressure supplied to the operating pressure chamber 54 of the chuck piston 25. Since the pressure is maintained, the cylinder is
When 22 is rotating together with the drive rod 17, the supply of the operating pressure to the operating pressure supply port 42 is released, and the rotational rubbing surface between the outer peripheral surface of the cylinder 22 and the inner peripheral surface of the outer sleeve 31 and By eliminating the pressure acting on the O-rings 45, 46 during that time, wear of the O-rings 45, 46 can be reduced.

On the other hand, when releasing the gripping of the drill rod R by the plurality of chuck jaws 27, the pilot pressure (hydraulic pressure) for releasing the non-return from the pilot pressure supply port 71 to the pilot pressure chamber 76 through the annular communication groove 73 and the like. The pilot pressure pushes up the check release piston 63, and the check valve
52 poppet valve 56 is pushed open from seat 55, and this check valve
The operating pressure of the chuck piston in the operating pressure chamber 54 held by the operating pressure chamber 52 is released. Therefore, the chuck piston
25 is returned downward by return spring 36,
Each chuck jaw 27 is returned to its enlarged diameter by a spring 37 and retracts from the drill rod R.

Further, since the cylinder 22 is integrally attached to the lower end of the drive rod 17, and the chuck device 18 is constituted by the chuck piston 25, the chuck jaw 27 and the operating pressure supply means 41, the conventional upper end of the drive rod is formed. The height can be further reduced as compared with the case where the chucking device is located at a lower position. By reducing the total height, the work of extending the drill rod R for boring can be performed more easily.

Further, since the chuck device 18 stably holds the drill rod R near the hole of the boring hole, it is possible to suppress the vibration of the drill rod R and reduce the bending of the hole in the boring hole. be able to. Further, since the cylinder 22 is provided integrally with the drive rod 17, the number of parts can be reduced as compared with the conventional chuck device, and maintenance can be performed easily.

In addition, since the outer side of the cylinder 22 which rotates together with the drive rod 17 is covered with the outer sleeve 31, the rotating portion is hardly exposed, so that it is safe. If the outer sleeve 31 is securely fixed, the vibration of the cylinder 22 can be effectively suppressed.

[0037]

According to the first aspect of the present invention, the cylinder is provided at the lower end of the drive shaft so as to constitute the chuck device. Therefore, compared with the conventional case where the chuck device is located at the upper end of the drive shaft. The overall height can be kept low, and the workability during rod extension work, the rod stability during boring drilling, and the straightness can be improved. Further, since the cylinder is provided integrally with the drive shaft body to simplify the structure, the number of parts can be reduced as compared with the conventional chuck device, and the maintainability can be improved.

According to the second aspect of the present invention, the cylinder that rotates together with the drive shaft can be covered by the outer cylinder.

According to the third aspect of the present invention, since the operating pressure supplied to the chuck piston is held by the check valve, the operating pressure is supplied to the operating pressure supply port when the cylinder is rotating. When released, the pressure acting on the rotary seal between the outer peripheral surface of the cylinder and the inner peripheral surface of the outer cylinder can be reduced, and wear of the rotary seal can be reduced.

According to the fourth aspect of the present invention, since the check release piston is provided so as to be able to advance and retreat with respect to the check valve, the operating pressure is supplied to the check release piston and the check release piston is operated by the check release piston. By simply opening the stop valve, the operating pressure on the chuck piston held by the check valve can be easily released, and the rod gripping by the rod gripper can be easily released.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a boring chuck device according to the present invention.

FIG. 2 is a front view showing a driving device for forcibly rotating and vertically driving a boring drive rod provided with the chuck device.

[Explanation of symbols]

 R Rod for boring (drill rod) 17 Drive rod as drive shaft 22 Cylinder 25 Chuck piston 27 Chuck jaw as rod gripper 31 Outer sleeve as outer cylinder 41 Working pressure supply means 42 Working pressure supply port 44 Annular 45, 46 O-ring as rotary seal 52 Check valve 63 Piston for check release

Claims (4)

[Claims] 1. A boring chuck device mounted on a cylindrical drive shaft body to which a rotational force and a vertical force are applied while a boring rod is inserted, wherein a lower end portion of the drive shaft body is provided. A cylinder integrated concentrically with a cylinder, a chuck piston slidably provided in the cylinder, a rod gripper pressed inward in the radial direction by the chuck piston, and an operation of supplying operating pressure to the chuck piston A boring chuck device comprising: a pressure supply unit. 2. The boring chuck device according to claim 1, further comprising an outer cylindrical body rotatably fitted on an outer peripheral portion of the cylinder. 3. An annular communication provided between the outer peripheral surface of the cylinder and the inner peripheral surface of the outer cylinder and communicating with the operating pressure supply port provided on the outer peripheral surface of the outer cylinder. A rotating seal provided between the outer peripheral surface of the cylinder and the inner peripheral surface of the outer cylinder along the communication groove; and a working pressure supplied to the chuck piston through the communication groove provided inside the cylinder. 3. The boring chuck device according to claim 2, further comprising: a check valve for holding the chuck. 4. The boring chuck device according to claim 3, further comprising a check release piston provided to be able to move forward and backward with respect to the check valve.