JPH08270361A - Return stopping device for thread joint part of boring rod - Google Patents

Abstract

PURPOSE: To prevent the thread part from returning at reverse rotation, in a thread type boring rod. CONSTITUTION: The extreme end and the rear end joint parts 24, 25 are threadedly engaged with each other, so as to mutually join together boring rods 22. The exterme end of the joined boring rods 22 is provided with a spread bit device. A plurality of vertical grooves 34 are provided on the outer circumference of the rear end joint part 25. Outer vertical linear projections 35 are provided on the outer circumference of the extreme end joint part 24, and wide vertical grooves 36 wider than the vertical grooves 34 are provided between the outer vertical linear projections 35. Inner vertical linear projections 38 to be inserted into both vertical grooves 34, 36 are provided on the inner circumference of a socket 37 to be fitted to both joint parts 24, 25 from the outside. Even if after drilling the boring rod 22 is rotated in the reverse direction and the threaded engagement is loosened, the outer vertical linear projections 35 of the extreme end joint part 24 are locked with the inner vertical linear projections 38 of the cylindrical socket 37.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excavating device used for excavating a buried pipe in the ground for a water well, anchor work, landslide prevention, etc. And a detent device for a threaded joint in a boring rod.

[0002]

2. Description of the Related Art Conventionally, in a boring for embedding a buried pipe made of steel pipe or the like, a bit device provided at the tip of the buried pipe is shocked to perform excavation while rotating, and along with the excavation, the buried pipe is replenished to advance. I am doing
In order to facilitate the insertion of the buried pipe into the ground, a bit device having a hole diameter larger than that of the buried pipe is used. And in order to pull up and collect the bit device after excavation,
An expanding bit device has been developed which can be retracted from the tip of the buried pipe and can expand and reduce the diameter of the perforation. As the expanding bit device, the same applicant discloses in Japanese Patent Application Laid-Open No. 6-330686 that the impact force and rotation of an air hammer are applied. A connecting hole is formed at the tip of the device that receives the force, and a connecting shaft provided at the base end of the bit device is rotatably connected in the connecting hole, and the bit device is circumferentially predetermined with respect to the device. In a drilling device that rotates by an angle to expand a drilling diameter of the bit device and drills while rotating the bit device by rotating the device, a rotation transmission pin is provided on an inner peripheral surface of the connecting hole,
An engagement groove that engages with the rotation transmission pin and enables the bit device to rotate by the predetermined angle is formed in the coupling shaft, and the rotation transmission pin is provided on one side in the circumferential direction of the engagement groove via the rotation transmission pin. It proposes an excavating device provided with a transmission engaging portion for transmitting the rotation of the device to the bit device. In addition, Japanese Patent Fair 3-2
In the excavation device of Japanese Patent No. 1717, when the device rotates in the excavation direction, one end of each of the two bit devices both protrudes from the outer peripheral surface of the device by a predetermined excavation amount (the same column, column 38 to 38). (42 line) and the drilling diameter increases, while the bit device etc. is pulled out from the drill pipe after completion of the excavation, but at that time, if the hammer cylinder is rotated in the direction of the arrow, the bit device will have teeth opposite to those at the time of excavation. After the operation, the diameter is equal to or smaller than the lower end of the device (the same publication, column 6, line 42 to column 7, 3).
It has been proposed to reduce the number of lines. The expansion bit devices of these excavators are provided at the tip of the boring rod, and as this type of boring rod, those in which screw parts provided at both ends are screwed and connected are used.

[0003]

In both of the conventional excavators described above, the boring rod is rotated to one side to enlarge the bit device, and the boring rod is rotated to the other side after excavating by the one side rotation. Then, the bit device is reduced in size, the reduced bit device is pulled out, and a plurality of boring rods joined by screw portions are used by releasing the joined screw portions. However, due to the soil condition in which the bit device at the tip of the boring rod is pressed into contact, the screw part of the boring rod returns before the bit device shrinks due to resistance when rotating on the other side, and the screw part disengages and separates. There was a problem in that it was impossible to collect the enlarged bit device at the tip because only this part came off.

Therefore, the present invention provides a detent device for a threaded joint in a boring rod that can reliably recover the bit device at the tip without the screw part coming off even if the boring rod is rotated in the direction opposite to the excavation direction. The purpose is to

[0005]

According to a first aspect of the present invention, a tip and a rear end joint portion are provided on a boring rod, and the boring rods are joined to each other by a screw portion provided on these joint portions, and a plurality of these are joined. A boring rod in which an expanding bit device is provided at the tip of a boring rod, and the boring rod is rotated to one side to expand the drilling diameter of the expanding bit device, and the boring rod is rotated to the other side to return. In the detent device for screw joints, a plurality of vertical grooves are provided on the outer periphery of the rear end joint portion, and outer vertical protrusions are provided on the outer periphery of the tip joint portion, and the vertical groove is provided between the outer vertical protrusions. A wide vertical groove that is wide in the circumferential direction is provided, and an inner vertical protrusion that is inserted into the both vertical grooves is provided on the inner circumference of the socket that is externally fitted to both joint portions.

The invention of claim 2 provides a plurality of the vertical grooves corresponding to the wide vertical grooves.

[0007]

In the structure according to the above-mentioned claim 1, in the state where the socket is temporarily fixed to the rear side of the front end joint portion, the front end joint portion is screwed into the rear end joint portion to form the boring rod on the front end side and the rear end side. After joining, insert the inner vertical ridges of the socket into both vertical grooves. Then, after excavation is completed, the boring rod is rotated in the direction opposite to the screw engagement, and when the screw engagement is loosened, the outer vertical protrusion of the tip joint part is locked to the inner vertical protrusion of the socket, and further the socket The rotation of the rear end joint portion is transmitted to the front end joint portion by the engagement between the inner vertical protrusion and the vertical groove.

In the above-mentioned structure, a plurality of vertical grooves on the rear end side are provided corresponding to the wide vertical grooves on the front end side, and two or more vertical grooves are provided on one wide vertical groove. Therefore, with the front end joint part completely screwed into the rear end joint part, the outer vertical projection on the front end side partially overlaps with the one vertical groove position on the rear end side. Even if it is closed, since the other vertical groove is positioned in communication with the wide vertical groove at the tip,
The inner vertical protrusion of the socket can be reliably inserted into the vertical groove of the rear end joint portion.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 10 show an embodiment of the present invention. First, an example of an enlarged bit device used in the present invention will be described. In FIGS. 6 to 10, a bit casing is provided at the tip of an embedded pipe 1 made of a steel pipe or the like. The pipe 2 is welded, and the casing pipe 2 has a thick portion 4 at the tip via an inner peripheral step portion 3 on the inner side. An air hammer 5 is inserted into the buried pipe 1, and a tube portion 7 at the base end of the device 6 is connected to the air hammer 5.
A spline groove 8 is integrally formed on the outer periphery of the air hammer 5, and the spline groove 8 is fitted in the vertical groove 9 of the air hammer 5 so that the rotation of the air hammer 5 is transmitted to the device 6. Further, the air hammer 5 has a built-in hammer piston 5A which uses compressed air or the like as a power source, and the hammer piston 5A strikes the cylindrical portion 7 to transmit an impact force. A plurality of discharge grooves 10 for discharging excavated earth and sand and the like above the buried pipe 1 are provided on the outer periphery of the device 6.
And a peripheral stepped portion 11 that engages with the inner peripheral stepped portion 3 of the bit casing pipe 2. A connecting hole 12 is formed on the tip side of the device 6 so as to be eccentric with respect to the axis of the device 6, and a rotation transmitting pin 13 is laterally provided facing the inner surface of the connecting hole 12.
Is detachably fixed to a mounting hole 14 formed in the device 6. The connecting hole 12 has a connecting shaft at the base end of the enlarged bit device 15.
16 is inserted so as to be rotatable and vertically slidable in the drawing, and an engaging groove 17 is formed on the outer periphery of the connecting shaft 16 for engaging the rotation transmitting pin 13 and rotating the enlarged bit device 15 by a predetermined angle. There is. The engagement groove 17 is formed so that the rotation transmission pin 13 can rotate about 180 degrees along the outer periphery of the coupling shaft 16, and the rotation transmission pin 13 is provided on one side in the circumferential direction of the rotation transmission pin 13.
One side engagement surface 18 that is a transmission engagement surface that transmits rotation of the device 6 in one side direction R to the expansion bit device 15, and another side engagement surface 19 that transmits rotation of the other side direction to the expansion bit device 15. The engaging groove 17 has a width H1 larger than the diameter of the transmission pin 13 and is formed with a constant width in the circumferential direction at the width H1. The expansion bit device 15 is composed of a center mounting part 15A on the tip side and an eccentric mounting part 15B integrally provided behind the center mounting part 15A. The center axis C of the center mounting part 15A of the expansion bit device 15 is It is set so as to be concentric with the axis of the device 6 in the expanded state of the expansion bit device 15. Further, a plurality of chips 20 made of cemented carbide are provided at the tip of the expansion bit device 15. Then, as shown in FIG. 6, with the tip of the expansion bit device 15 grounded, the expansion bit device 15 is hit to start excavation, and when the expansion bit device 15 projects from the tip of the bit casing pipe 2, the device 6 gives a rotation with a hit. Then, the rotation transmitting pin 13 rotates 180 degrees along the engaging groove 17, whereby the expansion bit device 15 rotates 180 degrees with respect to the device 6, and in this state, the central mounting portion
15A is concentric with the axis of device 6 and has an eccentric mounting part
15B overhangs laterally and the perforation diameter P increases. Also, 1
The rotation transmitting pin 13 rotated by 80 degrees engages with the one side engaging surface 18 to increase the rotation of the device 6 in the one side direction R. Bit device 15
Is transmitted to When the excavation to a predetermined depth is completed by the impact force and the rotational force from the air hammer 5, the device 6 is rotated in the opposite direction, the expansion bit device 15 returns to its original position and is pulled up into the buried pipe 1. It can be collected and collected.

As shown in FIG. 3, the air hammer 5 is
At the rear end, a bit sub 21 that is both screw joints is provided,
The boring rod 22 is connected to the rear end of the bit sub 21 by screwing. The boring rod 22 is formed by fixing a tubular front end joint 24 and rear end joint 25 made of steel to the end of a rod body 23 made of a steel pipe by welding or the like. The tip joint portion 24 has a tapered male screw portion 26 at its tip, four flat surfaces 27 are formed on the outer periphery of the center at equal intervals in the circumferential direction, and the rod body 23 is baked at its rear end. Cushion part 28 to be fitted
Is provided, and an abutting portion 29 around which the tip of the rod body 23 is abutted is provided around the tip of the receiving cylinder portion 28, and the rear end of the rod body 23 is welded to the abutting portion 29. ing. The above-mentioned shrink fitting means that the rod main body 23 is heated and press-fitted into the receiving cylinder portion 28, and the rod main body 23 is cooled and then contracted to be crimped to the receiving cylinder portion 28. Also,
The rear end joint portion 25 has the male screw portion 26 at the rear end.
Has a taper-shaped female screw portion 30 to be screwed with, and four flat surfaces 31 are formed on the outer periphery of the center at equal intervals in the circumferential direction,
Also, a receiving portion for shrink-fitting the rod body 23 at its tip
32 is provided, and an abutting portion 33 with which the rear end of the rod body 23 abuts is provided around the tip of the receiving tube portion 32. The rod body 23 is welded to the abutting portion 33. There is. Then, the female screw portion 30 provided at the rear end of the boring rod 22 on the front end side is screwed with the male screw portion 26 provided at the front end of the boring rod 22 on the rear end side to join the boring rods 22 to each other. To do.

On the outer periphery of the rear end of the rear end joint portion 25,
A plurality of vertical grooves 34 are provided, and in this example, the vertical grooves 34 are formed at eight positions at equal intervals on the circumference, and the rear ends of the vertical grooves 34 are open, and a locking taper portion 34A is provided at the front end. , The bottom surface 34T of the vertical groove 34
Is formed on a flat surface. Further, a plurality of outer vertical ridges 35 are provided on the outer periphery of the tip of the tip joint portion 24, and a plurality of wide vertical grooves 36 are formed between these outer vertical ridges 35. The strips 36 are formed at four locations at equal intervals around the circumference, and as shown in FIG. 5, the width E of the wide vertical groove 36 in the circumferential direction is defined by the outer edges 34F, 34F of the adjacent vertical grooves 34. It is made equal to the direction width e. In this case, the circumferential width E
Is set to be equal to or larger than the circumferential width e, it is possible to provide two or more vertical grooves 34 corresponding to one wide vertical groove 36. A cylindrical socket 37 made of steel is externally fitted to the joint portions 24 and 25 in a loosely inserted state.
A plurality of inner vertical ridges 38 having substantially the same circumferential width as the vertical groove 34 are provided on the inner circumference of 37. In this example, the inner vertical ridges 38 are provided at four locations at equal circumferential intervals, The inner vertical protrusion 38 is formed in the wide vertical groove 36 and the vertical groove 34 so as to be inserted into and removed from the longitudinal direction of the boring rod 22, and an inclined guide surface 38A is formed at the tip of the inner vertical protrusion 38. Has been done. Also, the outer vertical ridge
An inclined guide surface 35A is formed at the rear end of 35. Reference numeral 39 in FIG. 3 denotes a boring device that pushes the boring rod 22 while rotating it, and has a male screw portion 39A screwed into the female screw portion 30 at the tip.

The operation of the above construction will be described below. As shown in FIG. 3, when the boring rod 22 at the rear end is pushed to a predetermined depth, the boring device 39 is removed and a new boring rod 22 is joined. In this case, the cylindrical socket 37 is inserted from the tip of the new boring rod 22, and the cylindrical socket 37 is provided above the tip joint portion 24 using a band (not shown) or the like, as shown in FIG.
Temporarily fix it. Then, the new boring rod 22 is rotated in the one side direction R, whereby the male screw portion 26 is changed to the female screw portion 30.
The boring rods 22 and 22 are joined to each other by screwing. In this case, since the female screw portion 30 and the male screw portion 26 are screwed together,
As shown in FIG. 1, the outer vertical protrusions 35 partially overlap the vertical grooves 34, and the upper portions of the overlapping vertical grooves 34 are closed. Since the above-described vertical groove 34 is formed, the width of the wide vertical groove 36 is 1 within the circumferential width E.
The two vertical grooves 34 are located with their tops open, and the cylindrical socket 37 can be set by inserting the inner vertical protrusion 38 into the wide vertical groove 36 and the opened vertical groove 34. The tip of 38 hits the locking taper portion 34A and the cylindrical socket 37
Is positioned. In this way, the plurality of boring rods 22 are joined, and the boring rod 22 is rotated in one direction R to excavate a predetermined depth. Then, as described above, this time, the boring rod 22 is rotated in the other direction to return to the original state of the enlarged bit device 15, and the bit casing pipe 2
Pull it up so that it can be inserted into. At that time, screw part 2
Since the boring rod 22 on the rear end side is rotated in the direction opposite to the one-sided direction R which is the screwing direction of 6 and 30, the tip joint part
There is a risk that only the boring rod 22 on the 24 side will rotate and the screw joint will return, but if the tip joint part 24 rotates in the direction opposite to the screwing, the outer vertical protrusion 35 will cause the inner vertical protrusion 38 of the cylindrical socket 37 to move.
The inner vertical protrusion 38 is the vertical groove of the rear end joint 25.
Since it is locked to 34, the tip side boring rod 22 rotates in the opposite direction. Further, the cylindrical socket 37 is not fixed to the joint portions 24 and 25 but is slidable in the length direction of the boring rod 22. It is inserted into the grooves 34 and 36. That is, even if the inner vertical protrusion 38 is caught on the rear end of the rear end joint portion 24 at the end of excavation, by rotating the boring rod 22 on the rear end side, the cylindrical socket 37 falls and the inside of the vertical groove 34. The inner vertical ridge 38 is inserted in. Then, in order to release the coupling between the boring rods 22 and 22, the cylindrical socket 37 is moved above the vertical grooves 34 and 36 and temporarily fixed, and the boring rod 22 on the rear end side is rotated to the other side and screwed. Unscrew the joint. Also, the flat surface 2
7 and 31 are used to lock a tool to the flat surfaces 27 and 31 when joining and unjoining the boring rod 22,
For example, when collecting the boring rod 22, a flat surface 31
The boring rod 22 at the rear end is rotated with the tool locked to the boring rod 22 at the front end to prevent it from rotating.

As described above, in this embodiment, in accordance with claim 1, the boring rod 22 has a front end portion 2a and a rear end joint portion 2b.
4 and 25 are provided, and the boring rod 22 is joined to each other by the male screw portion 26 and the female screw portion 30 provided on the joint portions 24 and 25, and the plurality of joined boring rods are joined together.
An expanding bit device 15 is installed at the tip of 22, and a boring rod
22 is rotated in the one-sided direction R and the drilling diameter P of the expansion bit device 15
And a plurality of vertical grooves 34 are provided on the outer circumference of the rear end joint portion 25, and the outer vertical projections are provided on the outer circumference of the tip joint portion 24. 35 and a wide vertical groove 36, which is wider in the circumferential direction than the vertical groove 34, is provided between the outer vertical projections 35, and the joint portions 24,
Since the inner vertical protrusion 38 that is inserted into both the vertical grooves 34 and 36 is provided on the inner circumference of the socket 37 that is fitted to the outside of the 25, the cylindrical socket 37 is temporarily fixed to the rear side of the tip joint portion 24. Then, the front end joint portion 24 is screwed into the rear end joint portion 25 to join the boring rods 22 on the front end side and the rear end side, and then the inner vertical protrusion 38 of the cylindrical socket 37 is inserted into the vertical groove 34 of the both. Performing excavation by inserting and placing in 36, after excavation, the boring rod 22 is rotated in the opposite direction to the screwing in order to return the expansion bit device 15, and even when the screwing is loosened, the tip joint portion 24 The outer vertical ridge 35 can be engaged with the inner vertical ridge 38 of the cylindrical socket 37 to transmit the rotation of the rear end joint part 25 to the tip joint part 24, and the enlarged bit device 15 after excavation can be reliably recovered. be able to.

Further, in this embodiment, a plurality of vertical grooves 34 are provided corresponding to the wide vertical grooves 36 in this embodiment.
Since one wide vertical groove 36 is provided with two or more vertical grooves 34 within the circumferential width, the rear end joint portion 25 is completely screwed into the rear end joint portion 24, and One vertical groove
Even if the outer vertical ridge 35 on the tip side partially overlaps with the 34 position, the other vertical groove 34 is positioned in communication with the wide vertical groove 36 at the tip, so that the inner vertical ridge 38 of the cylindrical socket 37 is It can be reliably inserted into the vertical groove 34 of the rear end joint portion 25, and the cylindrical socket 37 can be easily attached.

Further, as an effect of the embodiment, the outer vertical projection 35
Since the inner vertical ridges 38 and the inner vertical ridges 38 are provided correspondingly, the outer vertical ridges 35 are locked to the inner vertical ridges 38 and the rotation torque of the boring rod 22 on the rear end side is good for the boring rod 22 on the front end side. Can be transmitted to. Further, since the bottom surface 34T of the vertical groove 34 is formed as a flat surface, the inner vertical protrusion 38 can be smoothly inserted. Further, since the inclined guide surface 38A is formed at the tip of the inner vertical protrusion 38 and the inclined guide surface 35A is formed at the rear end of the outer vertical protrusion 35, the cylindrical socket 37 is joined from the rear end side. The parts 24 and 25 can be fitted over smoothly.

The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention. For example, as the expansion bit device, various types can be used other than the expansion bit device shown in the conventional example and the expansion blade expanding.

Further, it can be used for a boring rod of an excavator without an air hammer, and can also be applied to a device for pushing the boring rod at an angle. Further, it is also applicable to the one in which the rear end joint portion is provided with a male screw portion and the tip joint portion is provided with a female screw portion. If the socket is cylindrical, the outer peripheral side may be rectangular.

[0018]

According to the first aspect of the present invention, the tip and rear end joints are provided on the boring rod, the boring rods are joined to each other by the screw portions provided on the joints, and the tips of the plural boring rods are joined. Is provided with an enlarged bit device, the boring rod is rotated to one side to increase the drilling diameter of the enlarged bit device, and the boring rod is rotated to the other side to return to the screw joint portion of the boring rod. In the detent device, a plurality of vertical grooves are provided on the outer periphery of the rear end joint portion,
An outer vertical ridge is provided on the outer circumference of the tip joint part, and a wide vertical groove that is wider in the circumferential direction than the vertical groove is provided between the outer vertical ridges, and the inner circumference of the socket is fitted to both joint parts. A boring capable of reliably recovering the bit device at the tip without disengaging the threaded portion even if the boring rod is rotated in the direction opposite to the excavation direction by providing an inner vertical protrusion to be inserted into both the vertical grooves. A detent device for a threaded joint on a rod can be provided.

According to the second aspect of the present invention, a plurality of the vertical grooves are provided in correspondence with the wide vertical groove, the socket mounting work is easy, and the boring rod is rotated in the direction opposite to the excavating direction. It is possible to provide a detent device for a threaded joint in a boring rod that can reliably collect the bit device at the tip without the screw part coming off.

[Brief description of drawings]

FIG. 1 is a perspective view of a joint portion and a socket showing an embodiment of the present invention.

FIG. 2 is a sectional view of a boring rod showing an embodiment of the present invention.

FIG. 3 is a cross-sectional view of an excavating device showing an embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a state in which a socket is attached to the joint part according to the embodiment of the present invention.

5A and 5B are cross-sectional views of a joint portion and a socket showing an embodiment of the present invention, FIG. 5A shows a cross section of a wide vertical groove and a socket, and FIG. 5B shows a cross section of a vertical groove and a socket. Is shown.

FIG. 6 is a cross-sectional view of the expanded bit device according to an embodiment of the present invention in a returned state.

FIG. 7 is a cross-sectional view of a main part of an enlarged bit device before enlargement showing an embodiment of the present invention.

FIG. 8 is a cross-sectional view of an enlarged essential part of an enlarged bit device showing an embodiment of the present invention.

FIG. 9 is a bottom view of the enlarged bit device according to the embodiment of the present invention.

FIG. 10 is a cross-sectional view of the enlarged bit device in an enlarged state showing one embodiment of the present invention.

[Explanation of symbols]

 15 Enlarged bit device 22 Boring rod 24 Tip joint part 25 Rear end joint part 26 Male screw part 30 Female screw part 34 Vertical groove 35 External vertical ridge 36 Wide vertical groove 37 Cylindrical socket 38 Internal vertical ridge

Claims (2)

[Claims] 1. A boring rod is provided with a front end and a rear end joint part, and the boring rods are joined to each other by a screw part provided in these joint parts, and an enlarged bit device is provided at the tip of the plural boring rods joined together. In the detent device for the threaded joint in the boring rod, which rotates the boring rod to one side to expand the drilling diameter of the expansion bit device and rotates the boring rod to the other side to return. A plurality of vertical grooves are provided on the outer circumference of the end joint portion, and an outer vertical ridge is provided on the outer circumference of the tip joint portion, and a wide vertical groove that is wider in the circumferential direction than the vertical groove is provided between the outer vertical ridges, A screw contact in a boring rod, characterized in that an inner vertical protrusion that is inserted into the both vertical grooves is provided on an inner circumference of a socket that is externally fitted to both joint parts. Joint detent device. 2. The detent device for a threaded joint of a boring rod according to claim 1, wherein a plurality of the vertical grooves are provided corresponding to the wide vertical grooves.