JP2003172086A - Buffer structure for pipe body, and double-pipe excavator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a buffer structure for a pipe body, which protects a joint portion of pipes from being damaged by a driving force even if an outer pipe is formed of vinyl chloride or thin steel, thereby to positively propel the pipe body into the ground. <P>SOLUTION: The buffer structure for the pipe body is formed of a pipe body 20 and the pipe body 40 overlapping each other via a joint portion 3, to thereby transmit an axial force therethrough. The pipe body 40 arranged outside the joint portion 3 has a female screw 41 formed in an inner peripheral surface thereof, and the pipe body 20 arranged inside the joint portion 3 has a male screw 24 formed on an outer peripheral surface thereof. Then, a coil member formed of a resilient material 5 is entangled in a fitting gap which is formed when the female screw 41 is screwed onto the male screw 24. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorbing structure for a pipe and a double pipe excavating tool, and more particularly to a pipe to which an axial force is transmitted through a connecting portion formed by superposing the pipe and the pipe. TECHNICAL FIELD The present invention relates to a shock absorbing structure for a body and a double pipe type drilling tool.

[0002]

2. Description of the Related Art There is a double pipe type drilling tool for boring ground, rock, etc. as a connecting portion formed by overlapping pipes with each other. In the case of tunnel excavation and the like, a long-end first receiving method or a pipe roofing method is known as an example of an earth retaining method for preventing the collapse of fragile ground in front of and above the face. In these construction methods, the pipe bodies (steel pipes) divided into short pieces are connected to each other to a predetermined depth,
As a method of arranging the steel pipe in the ground, a double pipe type drilling tool as shown in FIG. 6 is used. In this tool, a ring bit c is attached to the tip of an outer pipe a placed in the ground via a top joint b, and an inner bit f is attached to the tip of an inner pipe d placed in the outer pipe a via a joint member e. Is mounted, and the rotational force and the striking force of the inner pipe d are transmitted to the inner bit f and the ring bit c for excavation. After excavating to a predetermined depth, the inner pipe d is pulled out together with the inner bit f, and the ring bit c, the top joint b, and the outer pipe a are left in the ground. Here, the rotational force and the striking force of the inner pipe d are transmitted to the ring bit c via the joint member e and the inner bit f, and only the striking force is received by the striking surface e1 of the joint member e by the top joint b. It is transmitted to the outer tube a by hitting the surface b1. Due to this striking force, a propulsive force of the outer pipe a continuous to the rear is generated in the ground.

[0003]

However, the conventional method has the following problems. <a> The striking force of the joint member e damages the connecting portion (screw connection or the like) between the outer pipe a and the top joint b,
It was difficult to push the outer pipe a into the ground. <B> As a measure to solve the above problem, there is one in which a cushioning material is attached to the striking surface e1 of the joint member e and the striking surface b1 of the top joint b, but the striking surface e1 of the joint member e is the outer tube a. Since the top joint b to be connected is hit hard, even if the cushioning material is attached, the outer tube a is impacted. In particular, when a pipe having a low connection strength such as a vinyl chloride pipe or a thin-walled steel pipe is used as the outer pipe a, the connecting portion is damaged and it is difficult to propel the outer pipe a into the ground. <C> In addition to the above, impact force, vibration, and noise at the time of impact have also been major problems.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems. Even when a vinyl chloride pipe or a thin steel pipe is used as the outer pipe, the connecting portion is damaged by the striking force. It is an object of the present invention to provide a shock-absorbing structure for a tubular body, which is capable of reliably propelling the tubular body into the ground. Another object of the present invention is to provide a shock absorbing structure for a tubular body, which can reduce impact force, vibration, and noise upon impact. The present invention is intended to achieve at least one of the above objects.

[0005]

In order to achieve the above object, in the shock absorbing structure for a tubular body of the present invention, an axial force is transmitted through a connecting portion formed by superposing the tubular bodies. In the buffer structure of the pipe body, the female screw is provided on the inner peripheral surface of the pipe body located outside the connection portion, and the male screw is provided on the outer peripheral surface of the pipe body located inside the connection portion. It is characterized in that a coil member made of an elastic material is wound in a fitting gap when a male screw is screwed.

The shock absorbing structure for a pipe body of the present invention is a shock absorbing structure for a pipe body in which an axial force is transmitted through a connecting portion formed by superposing the pipe body and the pipe body. Female thread is provided on the inner peripheral surface of the tubular body located on the outer side of the pipe, and a male thread is provided on the outer peripheral surface of the tubular body located on the inner side of the connecting portion, and an elastic material is provided in the fitting gap when the female thread and the male thread are screwed together. It is characterized in that it is formed by winding a coil member made of (1) and filling it with a coating material.

Further, the shock absorbing structure of the tubular body of the present invention is characterized in that the resin material urethane rubber is used as the elastic material.

The cushioning structure for a tubular body according to the present invention is a cushioning structure for a tubular body in which an axial force is transmitted through a connecting portion formed by superposing the tubular body and the tubular body. A female thread having at least two threads on the inner peripheral surface of the tubular body located outside of the connecting portion, and an external thread having at least two thread threads on the outer peripheral surface of the tubular body located inside the connecting portion. A coiled spring material is interposed between the end of the male screw and the end of the male screw, and one end of the spring steel is attached at a position displaced by one pitch from the end of either the female screw or the male screw. It is what

Further, in the double pipe type excavating tool of the present invention, excavating means is provided at the tips of the inner and outer double pipes to excavate by the rotating force and the striking force of the inner pipe, and at the same time, the striking force of the excavating means is removed. In a double pipe type excavating tool configured to be able to transmit to a pipe side, a shock absorbing structure for a pipe body according to any one of the above is used at a connecting portion between the excavating means of the double pipe type excavating tool and the outer pipe. It is characterized by that.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1 of the present invention will be described below with reference to the drawings. In the present embodiment, the case where the shock absorbing structure of the pipe body is used for the double pipe type excavation tool will be described as an example, but the pipe body and the pipe body may be overlapped to form the connection portion. Of course, it is possible to adopt the present invention.

<A> Double-pipe type excavating tool As shown in FIG. 1, the double-pipe type excavating tool 1 is constructed by providing an excavating means 2 at the tips of an outer pipe 40 and an inner pipe 50. The outer pipe 40 is inserted into the hole while excavating the hole in the ground. The inner pipe 50 is for transmitting the rotating force and the striking force to the excavating means 2. The excavation means 2 is
Inner bit 30 attached to the tip of the inner tube 50
And the ring bit 10 which is mounted on and engages with the outer peripheral surface of the inner bit 30. The rotating force and the striking force of the inner pipe 50 are transmitted to the inner bit 30, and the rotating force and the striking force are also transmitted from the inner bit 30 to the ring bit 10. The striking force of the ring bit 10 is transmitted to the outer pipe 40 via the top joint 20 and gives a propulsive force to the outer pipe 40.

Top joint The top joint 20 is a tubular body having substantially the same diameter as the outer pipe 40, and has a connecting portion 3 which overlaps the outer pipe 40 at one end (rear) thereof, as will be described later. Further, a locking portion 4 that locks with the ring bit 10 is provided at the other end (front) of the top joint 20. The locking portion 4 has, for example, a locking surface 21 protruding from the outer peripheral surface of the top joint 20, and the ring bit 10
A locking surface 13 is provided on the inner peripheral surface of the
3, the screws 22 and 14 are cut, the screws 22 and 14 are disengaged, and the screw end surfaces 23 and 15 facing each other are brought into contact with each other. By this locking portion 4, the striking force from the ring bit 10 is transmitted to the top joint 20, but the rotational force is not transmitted. Therefore, ring bit 1
The thread end surface 15 of 0 forms a striking surface, and the thread end surface 23 of the top joint 20 forms a receiving surface. An inner bit 30 is inserted through the inner diameter of the top joint 20.

Ring Bit The ring bit 10 is provided with a drill bit 11 at the tip,
The top joint 20 is provided at the rear end by the locking portion 4 described above.
Lock with the tip of. In the fitted state in which the ring bit 10 is fitted in the top joint 20, the screws 14 and 22 are disengaged from each other and the gap portion 4a is generated.
Can be slid in the axial direction, and the ring bit 10 can effectively transmit the striking force to the top joint 20. Further, an engagement surface 12 is provided on the inner peripheral surface of the ring bit 10 so as to engage with the outer peripheral surface of the inner bit 30 described later and rotate together.

Inner Bit The inner bit 30 has a plurality of excavating bits 31 on the tip surface.
And the female screw portion 33 is formed on the other end side,
A water supply passage 34 communicating with this is opened at the tip surface. The male screw portion 51 provided at the tip of the inner pipe 50 is screwed into the female screw portion 33, and the inner bit 30 is attached to the tip of the inner pipe 50. Water supply channel 52 of inner pipe 50 and inner bit 30
And the excavation water is supplied through these water supply paths 52 and 34. An engaging surface 32 that engages with the engaging surface 12 of the ring bit 10 is provided on the outer peripheral surface of the inner bit 30 so that the rotational force and the striking force of the inner bit 30 are transmitted to the ring bit 10. These engagement surfaces 1
By making the tapered surfaces 2 and 32, the engagement area becomes large, and the rotational force and the striking force are easily transmitted.

Since the double pipe type excavating tool 1 is constructed as described above, the rotational force and the striking force of the inner pipe 50 are transmitted to the ring bit 10 through the inner bit 30 and only the striking force is generated. It is transmitted from the striking face of the ring bit 10 to the outer pipe 40 through the receiving face (screw end face 23) of the top joint 20 and the connecting portion 3 between the top joint 20 and the outer pipe 40. The excavated earth and sand are transferred from the tip surface of the inner bit 30 to the inner space of the top joint 20 and the inner pipe 50.
It is conveyed by the mud discharge passage 8 formed by communicating the space between the outer pipe 40 and the outer pipe 40, and is discharged from the rear end portion of the outer pipe 40.

<B> Outer Tube The outer tube 40 is a tubular body such as a steel pipe or a vinyl chloride pipe that is cast in the ground, and is formed in an elongated tubular shape. Outer tube 40
Is, for example, a part of the supporting material that is formed to have a length of about 3 meters and an outer diameter of about 80 mm to prevent the collapse of the fragile ground in front of and above the face during tunnel excavation,
It forms part of a drainage pipe for groundwater. The size of the outer tube 40 is a design matter and can be appropriately selected according to the purpose of use. In addition, when the outer pipe 40 is used as a drainage pipe for ground water or the like, or when cement milk, chemical liquid, mortar, etc. are injected into the ground from the outer pipe 40,
The outer tube 40 is a perforated tube having a hole in its outer peripheral surface. The connecting portion 3 described later is formed on the side of the outer tube 40 that is connected to the top joint 20.

<C> Connection Portion In this example, the connection portion 3 is composed of a male screw portion 24 provided on the outer peripheral surface of the top joint 20 and a female screw portion 41 of the outer pipe 40 screwed to the male screw portion 24. As can be seen from FIG. 1, the male screw portion 24 and the female screw portion 41 have a fitting gap of approximately one ridge when they are screwed, and the elastic material 5 is coiled and inserted into the fitting gap. For the elastic material 5, for example, urethane rubber, natural rubber, cloth, or other resin material can be used. When the striking force of the ring bit 10 is transmitted to the connecting portion 3 via the top joint 20, the male screw portion 24 of the top joint 20 transmits the striking force to the female screw portion 41 of the outer pipe 40. Since the elastic material 5 is wound in a coil shape and inserted into the entire fitting gap of the portion 41, the elastic material 5 serves as a buffer member without damaging the screw portions 24 and 41, and the impact force is attenuated in the axial direction. The force can be transmitted to the outer tube 40. The outer tube 4
0 is provided with a male screw portion on the outer peripheral surface thereof, and a female screw portion which is screwed to the male screw portion is provided on the top joint 20. The part 3 may be configured. Further, the impact force buffering ability of the elastic material 5 is set to such an extent that the impact force necessary for propelling the outer tube 40 into the ground can be secured.

[0018]

Next, the case where the shock absorbing structure of the pipe body according to the present embodiment is used as the outer pipe of the double pipe type excavating tool will be described.

<A> The elastic material 5 wound in a coil shape is mounted in the thread groove of the male screw 24 of the set top joint 20 of the outer tube. The female screw 41 of the outer pipe 40 is screwed into the male screw 24 of the top joint 20. As a result, the cushioning member made of the elastic material 5 is inserted into the fitting gap between the male screw 24 and the female screw 41, and
0 is connected to the top joint 20, and the outer tube 40 is set. The top joint 20 and the ring bit 3
As described above, the screws 22 and 14 are unscrewed to form the locking portions 4 (screw end surfaces 23 and 15), and the striking force from the ring bit 10 is transmitted to the top joint 20, but the rotational force is transmitted. Will not be transmitted.

<B> The outer pipe is inserted and excavated by the inner bit 30 and the ring bit 10 by the rotating force and the striking force of the inner pipe 50.
The striking force transmitted from 0 to the ring bit 10 is transmitted to the top joint 20, and the outer pipe 4 continuous behind the top joint 20.
Propulsive force is generated to insert 0 into the ground. According to the present invention, since the elastic material 5 is coiled and inserted in the entire fitting gap between the male screw portion 24 and the female screw portion 41 in the connection portion 3 between the outer pipe 40 and the top joint 20, the elasticity is improved. The member 5 serves as a cushioning member, and the striking force is attenuated to transmit the axial force to the outer tube 40 without damaging the screw portions 24 and 41,
The outer tube 40 can be inserted into the ground. Also, multiple outer pipes 4 such as when used for drainage pipes for groundwater, etc.
When inserting 0 deeply into the ground while connecting 0, the buffer structure of the present invention can be used for the connecting portion between the outer tubes 40.

[0021]

Embodiment 2 of the Invention Outer tube 40 and top joint 2
The connection portion 3 with 0 may be formed by inserting the elastic material 5 in a coil shape into the fitting gap between the male screw portion 24 and the female screw portion 41, and inserting the coating material 6 made of silicon. (See Figure 2). By filling with the silicon coating material 6, the fitting gap of the connection part 3 can be closed to provide water blocking property, and further the buffering effect can be enhanced and the loosening prevention effect of the male screw part 24 and the female screw part 41 can be obtained. You can also have.

[0022]

Third Embodiment A coil-shaped elastic member 5 is not inserted in the fitting gap between the male screw portion 24 and the female screw portion 41,
It is also possible to simply fill the coating material 6 made of silicon.

[0023]

Fourth Embodiment of the Invention Outer tube 40 and top joint 2
The threaded portions 41 and 24 are formed in one part without forming the threaded portions 41 and 24 over the entire length of the connecting portion 3 where 0 overlaps, and the spring material 7 wound in a coil shape is interposed in the portion where the threaded portions 41 and 24 are not formed. Alternatively (see FIG. 3). For the spring material 7, a steel material such as spring steel or stainless steel, or a material having elasticity such as non-ferrous metal is used. That is, a female screw 41 having at least two threads is provided on the outer peripheral surface of the tip of the outer pipe 40 (the side connected to the top joint 20), and the inner peripheral surface of the rear end of the top joint 20 (the side connected to the outer pipe 40). A male screw 24 having at least two threads is provided, and a coiled spring material 7 is interposed between the end of the female screw 41 and the end of the male screw 24. As shown in FIG. 4, one end 71 of the spring member 7 is bent to form the top joint 20.
It is attached to the outer peripheral surface at a position shifted by one pitch from the end of the male screw 24. Since the male screw 24 and the female screw 41 have at least two threads, the male screw 24 and the female screw 4 are
When 1 is fitted in one thread, the spring material 7 fits in the next thread, and the spring material 7 can be interposed by screwing as it is. The spring member 7 may be attached to the inner peripheral surface of the outer pipe 40 at a position displaced by one pitch from the end of the female screw 41.

[0024]

Fifth Embodiment of the Invention As shown in FIG. 5, a gap portion 4a of a locking portion 4 between a ring bit 10 and a top joint 20.
Alternatively, the spring material 7 described in the fourth embodiment may be interposed. In this case, the striking surface (screw end surface 15) of the ring bit 10 and the receiving surface (screw end surface 2) of the top joint 20.
Since the cushioning material is interposed between the top joint 20 and 3), the top joint 20 can use an inexpensive commercially available steel material without using hardened steel. Further, if the engaging portion 4 that can engage the connecting portion of the outer pipe 40 with the ring bit 10 is formed, the top joint 20 can be omitted and the outer pipe 4 can be directly connected.
0 can be connected to the ring bit 10 (drilling means 2).

[0025]

Since the present invention is as described above, the following effects can be obtained. <B> Since the buffer member is provided at the connecting portion between the outer pipe side and the top joint or the connecting portion between the outer pipe side and the excavating means, the impact force transmitted to the outer pipe side can be attenuated. In addition, the screw member of the connection portion is not damaged. <B> Therefore, even when a vinyl chloride pipe or a thin steel pipe is used as the outer pipe, it is possible to prevent damage to the connection part with the top joint and reduce impact force, vibration, and noise at the time of impact. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view when a shock absorbing structure for a pipe body according to the present invention is used in a double pipe excavating tool.

FIG. 2 is a sectional view of a shock absorbing structure for a tubular body of the present invention.

FIG. 3 is a cross-sectional view showing another embodiment.

FIG. 4 is a perspective view of coiled spring steel.

FIG. 5 is a sectional view showing another embodiment.

FIG. 6 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

1 ... Double pipe type drilling tool 2 ... Excavating means 3 ... Connection part 4 ··· Locking part 5 ··· Elastic material 6 ... Coating material 7 ... Spring material 10 ... Ring Bit 12 ... engaging surface 13 ... Locking surface 20 ... Top joint 21 ... Locking surface 24 ... Male screw 30 ... Inner Bit 32 ... Engaging surface 40 ... Outer tube 41 ... Female thread 50 ... Inner tube

Continued front page    (72) Inventor Atsumi Watanabe             13 Takahashimoto, Shioki, Shikura-machi, Iwaki, Fukushima Prefecture               Iwaki Iron Works Co., Ltd. F-term (reference) 2D029 DA02

Claims (5)

[Claims] 1. A buffer structure for a tubular body, in which an axial force is transmitted through a connecting portion formed by superposing the tubular body and the tubular body, wherein the inner periphery of the tubular body is located outside the connecting portion. A female screw is provided on the surface, a male screw is provided on the outer peripheral surface of the tubular body located inside the connection portion, and a coil member made of an elastic material is wound in a fitting gap when the female screw and the male screw are screwed together. Characteristic, buffer structure of tube. 2. A buffer structure for a tubular body, in which an axial force is transmitted through a connecting portion formed by superposing the tubular body and the tubular body, wherein the inner periphery of the tubular body is located outside the connecting portion. A female screw is provided on the surface, a male screw is provided on the outer peripheral surface of the tubular body located inside the connection portion, and a coil member made of an elastic material is wound into the fitting gap when the female screw and the male screw are screwed together, and the coating is performed. A cushioning structure for a tubular body, characterized by being filled with material. 3. A cushioning structure for a tubular body according to claim 1 or 2, wherein a resin material is used for the elastic material. 4. A buffer structure for a tubular body, in which an axial force is transmitted through a connecting portion formed by superposing the tubular body and the tubular body, wherein the inner periphery of the tubular body is located outside the connecting portion. A female thread having at least two threads is provided on the surface, and a male thread having at least two threads is provided on the outer peripheral surface of the pipe body located inside the connection portion, and between the end of the female thread and the end of the male thread. A cushioning structure for a tubular body, wherein a spring material wound in a coil shape is interposed, and one end of the spring steel is attached at a position displaced by one pitch from the end of either the internal thread or the external thread. 5. A double pipe constructed such that excavating means is provided at the tips of the inner and outer double pipes to excavate by the rotating force and the striking force of the inner pipe, and the striking force of the excavating means can be transmitted to the outer pipe side. In the double-drilling tool, the shock-absorbing structure of the pipe body according to any one of claims 1 to 4 is used for a connecting portion of the double-drilling tool with the outer pipe. , Double pipe drilling tool.