JP2004190758A - Connection structure of casing pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connection structure of casing pipes allowing the casing pipes to be rotated each other. <P>SOLUTION: In this connection structure of the casing pipes 1 for inserting the plurality of cylindrical casing pipes 1 in an excavated hole excavated with an excavating tool in a connected state in the axial O direction, the pair of casing pipes 1 connected to each other are so formed that one connection male socket 2 can be fitted to the other connection female socket 3, and annular grooves 5 and 7 are formed in the outer peripheral surface of the connection male socket 2 and the inner peripheral surface 6 of the connection female socket 3 opposed to each other so as to be extended in a circumferential direction. A locking member 8 elastically deformable in the radial direction of the casing pipes 1 is installed in an annular hole formed by the alignment of the annular grooves 5 and 7 with each other. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a casing pipe connection structure for connecting a plurality of cylindrical casing pipes in an axial direction thereof to be inserted into a borehole drilled by a drilling tool.
[0002]
[Prior art]
Generally, the strength of the ground itself is increased by constructing casing pipes (steel pipes) deep underground on unstable ground or rock, or in the axial or diagonal direction of the tunnel prior to excavation when constructing a tunnel. It has been practiced to reinforce the ground of the wall surface by constructing a casing pipe.
Conventionally, the construction of such a casing pipe involves inserting the casing pipe into the drilling hole with the advance of the drilling tool to be drilled in advance, and when the drilling hole becomes deeper than the length of the casing pipe, Each time the casing pipe is inserted into the borehole, the next casing pipe is sequentially connected in the axial direction. In such a connection structure between casing pipes, screw fitting or taper fitting has been used. (For example, refer to Patent Document 1.)
[0003]
[Patent Document 1]
Japanese Patent No. 3229934 (Section 1, FIG. 1)
[0004]
[Problems to be solved by the invention]
By the way, in the connection structure by the screw fitting as described above, there is a problem that not only a long time is required for the connection operation, but also the direction of the force applied when inserting the casing pipe into the excavation hole is limited. . That is, if a force is applied in the direction in which the screw fitting is loosened, the connection between the casing pipes is disconnected, so that the force can be applied only in the direction in which the screw fitting is fastened. Also, in the connection structure by screw fitting or taper fitting, the casing pipes cannot rotate freely, for example, when the foreign matter is caught between the drilling tool and the casing pipe at the tip, the rotation of the drilling tool is reduced at the tip. When transmitted to the casing pipe, that is, when the drilling tool and the casing pipe rotate, all of the casing pipes rotate together, and there is a problem that the sliding resistance of the casing pipe makes it difficult to excavate. Was. Further, the connection between the casing pipes may be loosened due to such rotation or vibration during excavation, and the connection may be disconnected.
[0005]
The present invention has been made under such a background, and an object of the present invention is to provide a connecting structure of casing pipes in which connecting work is easy and casing pipes can rotate freely.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, the present invention proposes the following means.
The connecting structure of the casing pipe according to the present invention is a connecting structure of casing pipes for connecting a plurality of cylindrical casing pipes in an axial direction thereof and inserting them into an excavation hole excavated by an excavating tool. The pair of casing pipes to be connected are such that a connecting male socket of one casing pipe can be inserted into a connecting female socket of the other casing pipe, and an outer peripheral surface of the connecting male socket and the connecting female socket facing each other. An annular groove is formed on the inner peripheral surface of the casing pipe so as to extend in a circumferential direction, and the annular groove is formed by matching these annular grooves with each other. The pair of casing pipes are connected in the axial direction by interposing a suitable locking member.
[0007]
In the connecting structure of the casing pipe of the present invention, since the engaging members elastically deformable in the radial direction of the casing pipe are connected by being interposed in the annular holes defined by the annular grooves facing each other, the connecting is performed. The work is easy and the casing pipes are rotatably connected to each other. For example, when a locking member is attached to an annular groove formed on an outer peripheral surface of a connecting male socket of a casing pipe and a connecting male socket is inserted into a connecting female socket having an annular groove formed on an inner peripheral surface, a connecting female socket is formed. The outer diameter of the locking member is elastically deformed so that the outer diameter of the locking member is reduced in accordance with the inner diameter of the socket, and the outer diameter of the locking member is increased by the matching of the annular grooves. The connection structure is such that the stop member is engaged. That is, since the connection is made by simply inserting the connecting male socket into the connecting female socket without rotating the casing pipe as in screw fitting, the connecting operation is easy. Further, the annular groove and the locking member are engaged in the axial direction but not in the circumferential direction, so that the casing pipes are rotatable. This prevents the casing pipes from being disconnected from each other even when a force is applied in the circumferential direction when the casing pipe is inserted into the drilling hole. The rotation of the casing pipe is not transmitted, and an increase in sliding resistance can be suppressed. In addition, since the annular groove and the locking member are securely engaged, the connection is not disconnected even by vibration during excavation, and the casing pipes can be reliably connected to each other.
[0008]
Further, in the connecting structure of the casing pipe according to the present invention, in the connecting structure of the casing pipe, the locking member is attached to the annular groove on one of the outer peripheral surface and the inner peripheral surface. An inclined surface that is inclined with respect to the axis is formed at the tip of the other peripheral surface.
[0009]
In the connecting structure of the casing pipe of the present invention, the locking member is mounted on the annular groove of one of the outer peripheral surface of the connecting male socket and the inner peripheral surface of the connecting female socket, and An inclined surface that is inclined with respect to the axis is formed at the tip, so when the connecting male socket is inserted into the connecting female socket, it is guided by the inclined surface and elastically deforms in the direction in which the locking member contracts or expands. I do. For example, when a locking member is attached to the annular groove on the inner peripheral surface of the connecting female socket and an inclined surface is formed at the tip of the outer peripheral surface of the connecting male socket, the locking member is guided by the inclined surface and expanded when inserted. A connection structure that elastically deforms in the radial direction is obtained. Thereby, the locking member can be easily elastically deformed, and the connecting operation can be easily performed.
[0010]
Further, in the connection structure of the casing pipe according to the present invention, in the connection structure of the casing pipe, an outer peripheral surface and an inner peripheral surface are defined such that the plurality of annular holes are aligned in the axial direction. A plurality of the annular grooves are formed side by side in the axial direction.
[0011]
In the casing pipe connecting structure of the present invention, a plurality of annular grooves are formed in the outer peripheral surface of the connecting male socket and the inner peripheral surface of the connecting female socket, respectively, in the axial direction, and the plurality of annular holes are formed in the axial line. Are formed side by side in the direction and are connected by a plurality of locking members. Thereby, the connection strength can be improved.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 3 show partial cross-sectional views of a connecting male socket and a connecting female socket, which are connecting portions of a casing pipe. FIG. 1 shows a state before connection, FIG. 2 shows a state at the time of insertion, and FIG. It is a state of time. In each figure, (a) is a cross-sectional view taken along a plane perpendicular to the axis, (b) is a cross-sectional view taken along a plane passing through the axis, and (a) is a cross-section at the position of arrow X shown in (b). FIG. 4 is an enlarged view of a range Y indicated by a virtual line in FIG.
[0013]
The connecting structure of the casing pipe 1 is configured such that the connecting male socket 2 and the connecting female socket 3 are formed at both ends so that the casing pipe 1 can be connected in the direction of the axis O. The connecting male socket 2 is formed such that the outer peripheral surface 1a of the casing pipe 1 is reduced in diameter by one step, and the connecting female socket 3 is formed such that the inner peripheral surface 1b of the casing pipe 1 is increased in diameter by one step. The outer diameter of the connecting male socket 2 and the inner diameter of the connecting female socket 3 are set so that 2 can be fitted into the connecting female socket 3. On the outer peripheral surface 4 of the connecting male socket 2, three annular grooves 5 (circular grooves 5 a, 5 b, and 5 c) having a rectangular cross section and circling around the axis O (in order from the base end side of the connecting male socket 2) are provided. Are formed in the inner peripheral surface 6 of the connecting female socket 3 at positions opposed to the three annular grooves 5 at the time of connection. 3, annular grooves 7a, 7b, 7c) are formed in this order from the tip side. In other words, the annular groove 5 and the annular groove 7 are formed so that the annular groove 5 and the annular groove 7 coincide with each other at the time of connection, so that three annular holes 10 are defined.
[0014]
In the three annular grooves 5, locking members 8 (locking members 8a, 8b, 8c) which are elastically deformable in the radial direction of the casing pipe 1 are sequentially mounted from the proximal end side of the connecting male socket 2. ing. As shown in FIG. 1A, the locking member 8 has a shape in which a part of a ring-shaped member is cut, that is, a so-called C-shaped ring shape, and its cross-sectional shape is, as shown in FIG. It has a rectangular shape that is long in the O direction. In a normal state, the outer diameter of the locking member 8 is larger than the outer diameter of the outer peripheral surface 4 and the inner diameter is smaller than the outer diameter of the outer peripheral surface 4, that is, the outer diameter of the locking member 8 is within the radial thickness range. The surface 4 is located, and the locking member 8 is mounted in the annular groove 5 while being engaged in the direction of the axis O. The thickness of the locking member 8 in the radial direction and the depth of the annular groove 5 are substantially the same, and when the locking member 8 is reduced in diameter in the radial direction, the locking member 8 is inserted into the annular groove 5. Can be accommodated.
[0015]
An inclined surface 9 is formed at the distal end of the inner peripheral surface 6 of the connecting female socket 3 so as to incline with respect to the axis O and reduce the diameter from the distal end toward the proximal end. The side surface 7 'on the base end side of the groove 7 (the side surfaces 7'a, 7'b, 7'c in order from the distal end side of the connecting female socket 3) is formed to have the same inclination as the inclined surface 9. The diameter of a circle formed by the inclined surface 9 on the distal end surface of the connecting female socket 3 is formed to be slightly larger than the outer diameter of the locking member 8 in a normal state.
[0016]
The connection operation of the casing pipe 1 as described above will be described.
As shown in FIG. 1, a pair of casing pipes 1 are arranged such that the axes of the casing pipes 1 coincide with each other on the axis O, and the connecting male socket 2 and the connecting female socket 3 face each other. Then, the connecting female socket 3 is moved in a direction of inserting the connecting female socket 2 (leftward in the figure), and the tip of the connecting female socket 3 is inserted into the connecting male socket 2. When the connecting female socket 3 is further moved, the locking member 8c comes into contact with the inclined surface 9 and is guided to be inclined to be elastically deformed. In this state, the outer diameter of the locking member 8c is reduced to the inner diameter of the connecting female socket 3, and the locking member 8c is housed inside the annular groove 5c.
[0017]
When the connecting female socket 3 is further moved so that the annular groove 5c and the annular groove 7a coincide with each other, the locking member 8c expands in diameter, but is guided by the side surface 7'a to reduce the diameter again. Subsequently, even when the annular groove 5c and the annular groove 7b coincide with each other, the diameter of the locking member 8c is increased, and the diameter of the locking member 8c is reduced again by being guided by the side surface 7'b. In this state, the three locking members 8a, 8b, 8c are reduced in diameter as shown in FIG. Then, the connecting female socket 3 is moved so that the annular groove 5a and the annular groove 7a, the annular groove 5b and the annular groove 7b, and the annular groove 5c and the annular groove 7c are defined by the annular holes 10a, 10b, and 10c. As a result, the diameters of the locking members 8a, 8b, 8c are increased. That is, as shown in FIG. 3, the pair of casing pipes 1 are connected by interposing the locking members 8a, 8b, 8c in the annular holes 10a, 10b, 10c.
[0018]
In this state, as shown in FIG. 4, the locking member 8 is engaged with both the annular groove 5 and the annular groove 7, so that even if a force is applied in a direction to separate the casing pipes 1 from each other, The connection of the pipe 1 is not released, and the connection is not released by vibration during excavation. In particular, the wall faces of the annular groove 5 and the annular groove 7 which face in the separating direction are perpendicular to the axis O by making the annular grooves 5 and 7 have a substantially rectangular cross section. Can be linked. Since the connecting female socket 3 and the connecting male socket 2 are not engaged in the circumferential direction, the casing pipes 1 are rotatable in the circumferential direction.
[0019]
According to the connecting structure of the casing pipe 1 as described above, the connecting member in which the locking member 8 is interposed in the annular hole 10 defined by the annular groove 5 of the connecting male socket 2 and the annular groove 7 of the connecting female socket 3. With the structure, the connecting operation is only to insert the connecting female socket 3 into the connecting male socket 2, so that the casing pipes 1 can be easily connected. In addition, since the casing pipes 1 are rotatable in the circumferential direction, no problem is caused by applying a force in the rotating direction when inserting the casing pipe 1 into the excavation hole. Further, even when the excavating tool (not shown) and the casing pipe 1 rotate, only the casing pipe 1 at the tip rotates, and the rotation is not transmitted to the connected casing pipe 1 and the sliding resistance is reduced. The increase can be suppressed. This makes it possible to suppress the difficulty of the excavation work.
[0020]
A locking member 8 is attached to the annular groove 5 of the connecting male socket 2 to form an inclined surface 9 at the distal end of the connecting female socket 3, and the base side surface 7 'of each annular groove 7 is inclined. When the connecting female socket 3 is inserted into the connecting male socket 2, the engaging member 8 can be guided inclining and elastically deform in the direction of reducing the diameter. Thereby, the locking member 8 can be easily elastically deformed, and the connecting operation can be easily performed. Also, when the plurality of locking members 8 arranged in the direction of the axis O are respectively engaged with the plurality of annular holes 10, the work is easy. However, when there is one locking member 8 and one annular hole 10, the side surface 7 'does not have to be inclined, and the side surface 7'c does not have to be inclined for a plurality of innermost annular grooves 7c.
[0021]
Further, three annular grooves 5 are formed in the connecting male socket 2 and three annular grooves 7 are formed in the connecting female socket 3, and the casing pipe 1 is connected by the three locking members 8. The connection strength can be made higher than in the case of one or two. When a higher connection strength is required, the number of the annular grooves 5 and the annular grooves 7 may be increased and more locking members 8 may be used, so that the connection strength can be easily changed. .
[0022]
In the present embodiment, the locking member 8 has a rectangular cross section passing through the axis O, but may have a shape other than a rectangle, for example, a circle, an ellipse, or a triangle. In particular, when a locking member having a right-angled triangular cross section having an inclination such that the outer diameter decreases toward the distal end side of the connecting male socket 2, even if the connecting female socket 3 is not provided with the inclined surface 9, the locking member can be locked. The locking member can be reduced in diameter by the inclination of the member, and the connection can be prevented from being disconnected by the side surface of the locking member facing the base end side of the connecting male socket 2. Further, the locking member 8 may be mounted in the annular groove 7 of the connecting female socket 3. In this case, an inclined surface is formed so that the diameter increases from the distal end toward the proximal end.
[0023]
【The invention's effect】
As described above, according to the casing pipe connection structure of the present invention, the locking member elastically deformable in the radial direction of the casing pipe is connected to the annular groove formed on the outer peripheral surface of the connection male socket and the connection female. It is connected by being interposed in the annular hole defined by the annular groove formed on the inner peripheral surface of the socket, so the connection work is as simple as inserting the connection female socket into the connection male socket and easy connection can do. Further, since the casing pipes are rotatable with each other, it is possible to prevent disconnection due to the application of a force in the circumferential direction of the casing pipe. Further, even when the excavating tool and the casing pipe at the tip rotate, the rotation is not transmitted and the increase in the sliding resistance can be suppressed.
[0024]
In addition, a locking member is attached to an annular groove on one of the outer peripheral surface of the connecting male socket and the inner peripheral surface of the connecting female socket, and a distal end of the other peripheral surface has an axial line. Since the inclined surface is formed so as to be inclined, the engaging member is guided by the inclined surface and elastically deforms in a direction in which the diameter of the locking member is reduced or increased, so that the connecting operation can be easily performed.
[0025]
In addition, a plurality of annular grooves are formed in the outer peripheral surface of the connecting male socket and the inner peripheral surface of the connecting female socket, respectively, in the axial direction, and a plurality of annular holes are defined in the axial direction. Since the connection is made by a plurality of locking members, the connection strength can be improved.
[Brief description of the drawings]
FIG. 1A is a cross-sectional view taken along a plane perpendicular to an axis, and FIG. 1B is a cross-sectional view taken along a plane passing through an axis, in a state before connecting a casing pipe connecting structure according to an embodiment of the present invention. .
2A is a cross-sectional view taken along a plane perpendicular to the axis, and FIG. 2B is a cross-sectional view taken along a plane passing through the axis, in a state where the connecting structure of the casing pipe is inserted.
3A is a cross-sectional view taken along a plane perpendicular to the axis, and FIG. 3B is a cross-sectional view taken along a plane passing through the axis, in a state where the connecting structure of the casing pipe is connected.
FIG. 4 is an enlarged sectional view of a range Y in FIG. 3;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Casing pipe 2 Connecting male socket 3 Connecting female socket 4 Outer peripheral surface 5 and 7 of connecting male socket Annular groove 6 Inner peripheral surface of connecting female socket 8 Locking member 9 Inclined surface 10 Annular hole O Axis line

Claims (3)

A casing pipe connection structure for inserting and connecting a plurality of cylindrical casing pipes in the axial direction thereof into a borehole drilled by a drilling tool,
The pair of casing pipes connected to each other are configured such that a connecting male socket of one casing pipe can be fitted into a connecting female socket of the other casing pipe, and an outer peripheral surface of the connecting male socket and the connecting female socket facing each other. An annular groove is formed on the inner peripheral surface of the socket so as to extend in the circumferential direction, and an annular hole defined by the engagement of these annular grooves is elastically deformed in the radial direction of the casing pipe. A casing pipe connection structure, wherein the pair of casing pipes are connected in the axial direction by interposing a possible locking member. In the connection structure of the casing pipe according to claim 1,
Among the outer peripheral surface and the inner peripheral surface, the locking member is attached to the annular groove on one of the peripheral surfaces, and the tip of the other peripheral surface has an inclined surface inclined with respect to the axis. A connection structure for a casing pipe characterized by being formed. In the connecting structure of the casing pipe according to claim 1 or 2,
On the outer peripheral surface and the inner peripheral surface, a plurality of the annular grooves are respectively formed in the axial direction so that the plurality of the annular holes are defined in the axial direction. The connection structure of the casing pipe.

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