JPH0526000A - Connection structure of propulsion pipe - Google Patents

Abstract

PURPOSE:To obtain a connection structure which cannot rotate around the axis when plural pipes are mutually connected to constitute a propulsion pipe. CONSTITUTION:In connection structure of a propulsion pipe comprising mutual connection of plural pipes 1, 2, used in a propulsion construction method, in one pipe 1 to be connected, in its end portion, a fitting protrusion 12, is formed in parallel to the axis, and in the other pipe 2, in its end portion, a fitting recess 23 of a similar sectional form to the fitting protrusion 12 is formed in parallel to the axis. By fitting the protrusion 12 into the recess for jointing relative rotation of both pipes 1, 2 around the axis is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connecting structure for connecting a plurality of pipes to a propulsion pipe used in a propulsion method of propelling and burying a pipe while excavating the soil.

[0002]

2. Description of the Related Art As one of the propulsion methods used when connecting a mounting pipe to a main pipe buried in the soil, a rotary bit for excavation is set on the propulsion pipe and the pipe is press-fitted at the same time as the excavation in the soil. The method of promotion is disclosed in JP-A-2-18618.
It is disclosed in Japanese Patent No. In the technique disclosed in Japanese Patent Application Laid-Open No. 2-186183, a rotary shaft of a boring machine having a distal end to which a rotary bit is detachably mounted is inserted into a pipe to be buried, and the rotary bit rotates the rotary shaft. By driving and rotating it, it pierces the soil and propels the pipe, also pierces the main pipe with the rotating bit, presses the propelled pipe into the piercing portion and bury it in the soil. This is a connection method for connecting to the main pipe.

Further, Japanese Patent Application Laid-Open No. 61-162644 discloses a technique for connecting and propelling a pipe. The pipe connecting structure used in this propulsion method is a structure in which the tip of the succeeding pipe is fitted and bonded to the receiving end portion of the rear end of one pipe.

[0004]

However, in the above-mentioned propulsion method, the propulsion pipe formed by connecting a plurality of pipes is
The movement in the axial direction is suppressed by the propulsion unit at the rear end and the rotating bit at the front end, but the connecting portion between the pipes is likely to rotate about the axis line when a rotational force acts. Further, even when they are joined by adhesion, if the curing of the adhesive is insufficient, the action of the rotational force facilitates rotation around the axis.

In fact, in the above-mentioned propulsion method, the rotating bit tends to act on the propulsion pipe due to the rotating bit at the tip and the rotating force of the rotating shaft.
The connected pipes are relatively easy to rotate. However, when the propulsion pipe rotates around the axis, there arises a problem that the shape of the connection portion at the tip of the propulsion pipe does not match the perforation made in the main pipe at the connection portion with the main pipe.

In this case, it is necessary to rotate the propulsion pipe about its axis to adjust it to a predetermined angle. However, even if the rear end of the propulsion pipe is rotated on the ground side, its rotational force is There is a problem in that it is difficult to adjust the angle of the tip of the propulsion tube because it is difficult to be transmitted to the rotating bit at the tip because it is absorbed in the connection part on the way. Therefore, it is an object of the present invention to provide a connecting structure for connecting a propulsion pipe formed by connecting a plurality of pipes so that the connecting portion does not rotate around the axis.

[0007]

According to the propulsion pipe connection structure of the present invention made in view of the above problems, in a propulsion pipe connection structure for use in a propulsion method, a plurality of pipes are mutually connected. , A fitting convex portion parallel to the axis is formed at one end of the connecting pipe, and a fitting concave portion having substantially the same cross-sectional shape as the fitting convex portion is formed on the axial line at the end of the other pipe. The tubes are formed in parallel with each other, and the fitting convex portion and the fitting concave portion are fitted and connected to each other, so that both pipes are prevented from relatively rotating about the axis.

[0008]

According to the connecting structure of the propulsion pipe of the present invention having the above-described structure, the fitting convex portion formed parallel to the axis line at the connecting portion of one pipe to be connected and the axial line at the connecting portion of the other pipe. When the fitting concave portion formed in parallel with the fitting concave portion is fitted and connected, both the fitting convex portion and the fitting concave portion are formed parallel to the axis line, so that both pipes rotate relatively around the axis line. do not do.

Therefore, when the rotation of a part of the propulsion pipe is suppressed, the rotation of the other part of the propulsion pipe is also suppressed, and when the part of the propulsion pipe is rotated, the other part of the propulsion pipe also rotates.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A connecting structure for a propulsion pipe according to the present invention will be described below in detail with reference to the drawings showing an embodiment. FIG. 1 is a perspective view of a connection structure according to an embodiment of the present invention, and FIG. 4 is a partial cross-sectional side view illustrating a propulsion method.

In FIG. 1, a small diameter portion 12 having the same inner diameter as the other portions and a small outer diameter is formed at the connecting portion at the end of the pipe 1, and the outer diameter of the small diameter portion 12 is the thickness of the small diameter portion 12. The fitting recess 13 that is shallower and parallel to the axis is formed in a groove shape. A large-diameter portion 22 having an outer diameter equal to that of the other portion and having an expanded inner diameter so that the small-diameter portion 12 can be inserted is formed at a connecting portion at an end of the pipe 2 connected to the pipe 1, On the inner surface of the large-diameter portion 22, a fitting protrusion 23 parallel to the axis is formed in a shape that can fit into the fitting recess 13.

The difference between the inner diameter of the large-diameter portion 22 and the outer diameter of the small-diameter portion 12 is about 0.5 mm at most.
A large diameter portion 14 similar to the large diameter portion 22 of the pipe 2 is formed at the other end of the pipe 1, and the pipe 1 is provided at the other end of the pipe 2.
A small diameter portion similar to the small diameter portion 12 was formed. In this way, a plurality of pipes 1 each having a large-diameter portion and a small-diameter portion formed at both ends are prepared, and the small-diameter portion and the large-diameter portion are fitted and connected to each other. Of the propulsion tube 10 having the length

In FIG. 4, at the tip of the propulsion pipe 10,
The rotary bit 5 is set, the ground propulsion unit 6 and the rotary bit 5 are connected by the rotary shaft 7 that penetrates the inside of the propulsion pipe 10, and the rotary bit 5 is rotated to excavate the soil. While advancing, the plurality of pipes 1 are sequentially connected by the above connecting structure, and the propulsion pipe 10 is propelled while extending the length thereof.

At this time, even if the rotational force due to the rotation of the rotary shaft 7 or the rotary bit 5 tries to rotate the propulsion pipe 10, the rear end of the propulsion pipe 10 is fixed on the ground, and thus the propulsion pipe 10 is fixed. The entire rotation can be prevented.

When the rotary bit 5 at the tip reaches the main pipe 8 in the ground, the rotary bit 5 causes the main pipe 8 to move.
A perforation 9 for connection is drilled. The rotary bit 5 after drilling is
It may be collected without being dropped into the main pipe 8. Then, by fittingly connecting the connecting portion at the tip of the propulsion pipe 10 to the perforation 9, the propulsion pipe 10 serving as an attachment pipe is connected to the main pipe 8 for communication.

At this time, as shown in FIG.
When the shape of the tip of the main pipe 8 does not match the shape of the perforation 9 of the main pipe 8, when the rear end of the propulsion pipe 10 is rotated around the axis on the side of the ground propulsion unit, the rotational force is the connection of the pipes. Since it is transmitted to the tip of the propulsion pipe 10 by the connection structure of the fitting convex portion and the fitting concave portion of the portion, it can be adjusted so as to match the shape of the perforation 9 of the main pipe 8 as shown in FIG. is there. Such adjustment is particularly necessary when using a joint at the connection with the mains.

Further, an elastic seal material such as water-expandable rubber having a predetermined size and shape is preliminarily attached to the connecting portion of each pipe and the connecting portion between the tip of the propulsion pipe 10 and the main pipe 8. And good. Further, by making the outer diameter of the connecting portion between the respective tubes of the propulsion pipe 10 the same as the outer diameter of the other portions, it is possible to suppress an increase in frictional resistance in the propulsion direction, so that the necessary propulsion force is obtained. It can be suppressed and waste of energy can be prevented.

Further, in FIG. 1, the fitting concave portion is provided on the outer surface of the connecting portion of the pipe and the fitting convex portion is provided on the inner surface of the connecting portion of the pipe, but as shown in FIG. It may be provided on the inner surface of the connecting portion of the pipe, and the fitting convex portion may be provided on the outer surface of the connecting portion of the pipe.
Further, the cross-sectional shapes of the fitting convex portion and the fitting concave portion are not limited to the rectangular shape and the trapezoidal shape, and it is needless to say that the fitting convex portion and the fitting concave portion may be triangular or semicircular.

Further, it is sufficient if there are one or more fitting convex portions and concave portions, respectively, and the larger the number, the greater the effect of preventing rotation around the axis.

It is also possible to alternately fit and connect a pipe having small diameter portions at both ends and a pipe having large diameter portions at both ends. Further, as shown in FIG. 3, by arranging the fitting convex portions at unequal intervals, it is possible to provide a connection structure in which the fitting connection is not made unless a specific positional relationship is established.

The axial length of the fitting protrusion is
The length may be shorter than the axial length of the fitting recess. In addition, a pipe (for example, a pipe having fitting projections at both ends) having the same shape is connected to a joint having a shape corresponding to the shape of the connection (for example, a fitting recess at both ends). The connection may be made by a short pipe joint having a.
At this time, it is preferable that the outer diameter of the joint is as close as possible to the outer diameter of the pipe, from the viewpoint of friction resistance in propulsion. Rib-shaped projections may be provided to reinforce the strength.

The material of the pipe and the pipe joint may be synthetic resin such as vinyl chloride resin, polyethylene resin or the like, or metal. Further, in order to reinforce the outer surface of the pipe and the joint, glass fiber or the like may be wrapped around the outer peripheral surface. In the case of resin pipes and joints, they can be molded by known techniques such as extrusion molding and injection molding.

As described above, according to the connection structure of the fitting convex portion and the fitting concave portion provided on the pipes 1 and 2 as described above, both pipes 1 and 2 relatively rotate around the axis at the connecting portion. Therefore, if the rear end of the propulsion pipe 10 is fixed so as not to rotate around the axis, the tip of the propulsion pipe 10 can be prevented from rotating around the axis, and the connection with the main pipe 8 becomes accurate. The effect is obtained.

Also, since the tip can be turned by turning the rear end of the propulsion pipe 10 above the ground, adjustment can be performed from the ground so that the propulsion pipe 10 can be turned to be accurately connected to the main pipe 8. The effect of becoming like this is also obtained. In this way, by performing the accurate connection, it is possible to ensure the water stop at the connecting portion between the propulsion pipe and the main pipe, and to improve the quality of construction.

[0025]

As described above, according to the connection structure of the propulsion pipe of the present invention, since the connected pipes do not relatively rotate about the axis in the connection portion of the propulsion pipe, If you fix the part so that it does not rotate around the axis,
Since no part of the propulsion pipe rotates about the axis, a more accurate propulsion method can be achieved.

Further, by rotating a part of the propulsion pipe, for example, the rear end, all parts of the propulsion pipe, for example, the front end can be similarly rotated, so that the angle around the axis of the propulsion pipe can be arbitrarily adjusted. The effect of increasing the degree of freedom in construction can also be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view of a connection structure according to an embodiment of the present invention.

FIG. 2 is a perspective view of a connection structure of another embodiment.

FIG. 3 is a sectional view of a connection structure of another embodiment.

FIG. 4 is a partial cross-sectional side view for explaining a propulsion method using the propulsion pipe of the connection structure of the present invention.

FIG. 5 is a cross-sectional view illustrating a connection with a main pipe.

FIG. 6 is a cross-sectional view illustrating a connection with a main pipe.

[Explanation of symbols]

 1 pipe 2 pipe 13 fitting concave portion 14 fitting convex portion 23 fitting convex portion 10 propulsion pipe 8 main pipe

Claims (1)

Claim: What is claimed is: 1. A propelling pipe connection structure for use in a propulsion method, comprising a plurality of pipes interconnected to each other, wherein the connecting portion of one of the pipes to be connected is parallel to the axial line of the pipe. A fitting convex portion is formed, and a fitting concave portion having substantially the same cross-sectional shape as the fitting convex portion is formed in the connecting portion of the other pipe in parallel to the axis line, and the fitting convex portion and the fitting concave portion are formed. A connecting structure for a propulsion pipe, characterized in that both pipes are prevented from rotating relative to each other by fitting and connecting.