JP2002235492A - Casing for propulsing curve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To propel and bury a small-diameter pipe or a low-loading capacity pipe in a curve state. SOLUTION: A screw conveyor 17 connected by a universal joint is inserted into a casing 1, and short pipes 1A are connected to form the casing 1. Connecting sections 2 and 3 are provided at symmetrical positions on the diameter line of the pipe end section of each casing short pipe 1A, the connecting sections 2 and 3 are connected together so that the casing short pipe 1A can be turned in the required angular range by a vertical shaft 8, and the outer periphery of the connection ends of the casing short pipes 1A is sealed with a sealant 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a casing for propelling a curve of a buried pipe, which enables a low-load-bearing pipe such as a small-diameter pipe, a PVC pipe or the like to be buried in a curved portion underground.

[0002]

2. Description of the Related Art Conventionally, as a means for burying a pipe provided for various uses in the ground without digging the ground, a buried pipe is excavated at the digging trace while excavating the tip ground with a screw auger or the like. A pipe burying device is used in which the pipe is buried while being pushed forward and successively added.

In the above conventional pipe burying apparatus, the buried pipe is generally buried in a straight line. When the road is curved, the propulsion distance of the buried pipe is shortened, and a shaft is dug at several places. The buried pipe is bent and buried in such a way that it is sharpened and bent at that part.

[0004]

However, in the case where the pipe burying device is of a screw discharging system in which the screw is discharged through a casing through which the screw is inserted by using a screw blade of a screw conveyor, the conventional casing has a buried structure. It was difficult to follow the curve of the pipe, and it was difficult to propel the curve.

In order to allow the casing to bend, the upper half is shown in cross section in FIG. 7 and the outer periphery of the end of a short casing short pipe a is shown in FIG. The bearings b, c are provided with protrusions, and an O-ring d is interposed between the joining ends of the casing short tubes a, a, and the bearings b, c are tightened with some play with bolts e, e. In addition, there has been developed a casing which is capable of absorbing a slight bending of the casing short pipes a, thereby enabling curve propulsion.

However, according to the above structure, a large-diameter pipe can be propelled to a certain extent but cannot be bent to a degree applicable to a small-diameter pipe. In addition, the conventional method uses a muddy water discharging method, and thus has a problem that extra equipment must be brought in.

On the other hand, in the case of a pipe in which the buried pipe has a low propulsion load capacity such as a PVC pipe, a large pressing force needs to be applied in a state where the connection surface is bent in the case of transmitting the propulsive force at the distal end from the casing. In addition, when there is a large deviation due to poor correction of the course, the buried pipe has to be withdrawn and it is necessary to withstand this withdrawal force, but these techniques could not meet these requirements.

[0008] In the case of a muddy water supply and discharge mud pipe, the tip thrust cannot be transmitted, so that it cannot be constructed with a low load-bearing pipe such as a PVC pipe.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to make it possible to embed a low-load bearing pipe such as a small-diameter pipe and a PVC pipe in a curved state.

[0010]

As a means for solving the above-mentioned problems, the present invention relates to a casing through which a screw auger connected by a universal joint is inserted, wherein the casing is formed by connecting casing short pipes. Connecting portions are provided at symmetrical positions on the diameter line of the tube ends of the short tubes, and these connecting portions are connected by a vertical axis so that the casing short tube can pivot within a required angle range, and the outer periphery between the connecting ends of the casing short tubes. Is sealed with a sealing material.

With this arrangement, each casing short pipe constituting the casing follows the bending of the leading conduit in the bending direction and bends around the axis of the connecting portion so as to smoothly follow the short pipe and push the latter in later. The pipe can also be buried in a curve according to its bend.

As for the seal between the pipe ends of the casing short pipe, both sides of the connecting portion of the pipe end face of the casing short pipe are formed into a tapered surface, and the sealing material is straddled between the butted portions of the casing short pipe. An embodiment comprising a collar surrounding the outer periphery thereof, and a flexible sealing material such as an O-ring interposed between the inner surface of the collar and the outer peripheral surface of the short tube, between a tube end outer peripheral portion of the casing short tube; And an embodiment composed of bellows succeeding the above.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments shown in the drawings.

FIG. 1 is a plan view of the overall configuration of a buried pipe 2 using a curve propulsion casing 1 according to the present invention during curve propulsion. FIGS. 1A shows an embodiment of a connecting portion of 1A, 1A.

In the above embodiment, the connecting portions 2 and 2 are located at symmetrical positions on the diameter line of the tube ends of the casing short tubes 1A.
3 are fixed by welding or the like so as to protrude from the pipe end face so as to be overlapped with each other, and the pipe end faces on both sides of the connecting portions 2 and 3 are tapered surfaces cut so as to form a circular arc in plan view.

The connecting portions 2 and 3 have their bases 2a and 3a welded to the outer peripheral surfaces of the casing short tubes 1A and 1A, respectively.
a, 3a extending from the outer peripheral surface of the casing short pipes 1A, 1A to the adjacent casing short pipes 1A, 1A is separated from the outer peripheral surface of the casing short pipes 1A, 1A. Are fitted.

The casing short pipes 1A, 1A are provided with seal grooves 6, 6 on the outer periphery of the pipe ends.
O-rings 7, 7 serving as sealing materials are fitted to 6, and the O-rings 7, 7 are pressed against the inner peripheral surface of the collar 5 to perform a sealing function.

Therefore, the O-rings 7, 7 and the collar 5
The collar 5 is held by the connecting portions 2 and 3 by inserting and connecting the connecting pins 8 to the tips of the connecting portions 2 and 3 after that, and thereafter the casing short tubes 1A and 1A are The O-rings 7, 7 can always be pressed against the inner surface of the collar 5 irrespective of the bending of the casing short tubes 1A, 1A to provide a sealing function, regardless of the bending of the casing short tubes 1A, 1A. Complete. The sealing material is not limited to the O-ring, but may be of any other form as long as it can seal between the casing short tube 1A and the collar 5.

In FIG. 1, reference numeral 9 denotes a propulsion device installed in a starting pit 10, and a propulsion device main body 12 is mounted on a base 11 installed at the bottom of the starting pit 10 so as to be able to advance and retreat in the direction of propulsion of the buried pipe. The propulsion device main body 12 is provided with propulsion hydraulic cylinders 13 fixed thereto.
3a and 13a are reaction force receivers 14 fixed to the wall of the starting pit 10.
The propulsion device body 12 is driven in the direction of buried pipe propulsion by extending the hydraulic cylinders 13, 13.

The tube receiving portion 15 on the front of the propulsion device main body 12
A screw conveyor 17 is connected to an output shaft 16 driven by a motor (not shown) mounted on the propulsion device main body 12 through a speed reducer. The conveyor 17 is driven to rotate. The screw conveyor 17 is one in which one casing short pipe is used as one unit and sequentially connected by a universal joint (such as a cruciform joint). It is made to excavate.

FIG. 6 shows an example of a joint portion of a small-diameter (200-300 mmφ) PVC pipe 19, 19 (buried pipe) to be buried. The connection ends are substantially the same as the length of the pipe 1A, and the connection ends thereof are the same as those of the casing short pipe 1A.
A seal groove 20 is provided around the outer periphery of the pipe end. An O-ring 21 as a sealing material is fitted in the groove 20. The O-ring 21 is provided on the inner peripheral surface of a collar 22 made of stainless steel or the like. They are pressed against each other to perform a sealing function.

A ring-shaped cushioning material 23 made of rubber or the like having a high cushioning property is interposed between the pipe end faces of the PVC pipes 19, 19 to prevent stress concentration on the pipe end faces during bending, and to provide a cushioning material. By utilizing the elastic deformation of the thrust 23, the thrust is vertically dispersed.

FIG. 1 (B) is an enlarged view of the front end portion of the leading conduit 24, and a cutting edge 25 is provided at the leading end of the leading conduit 24. The cutting edge 25 is provided between the leading conduit 24 and the leading conduit 24. A plurality of direction correcting cylinders 26, 26 interposed as an equiangular arrangement
.. Can be bent by swinging the head in an arbitrary direction with respect to the leading conduit 24. As for the direction changing means of the blade 25, the head may be swung via a wire in addition to the cylinders 26, 26.

Next, the operation of the above embodiment will be described.

In the shaft 10, a screw conveyor 17 is connected to an output shaft 16 of the propulsion device main body 12, and a casing short pipe 1A is connected to a pipe receiving portion 15 of the propulsion device main body 12.
And a tip conduit 24 externally fitted thereto is brought into contact therewith, the screw conveyor 17 is driven to rotate, and the propulsion hydraulic cylinder 13 of the propulsion device 9 is extended while excavating the ground with the cutter head 18 at the tip of the screw conveyer. 1A and leading conduit 24 are advanced.

When the pushing is completed, the propulsion device main body 12 is pulled back, and the next screw conveyor 17, the casing short pipe 1A, and the buried pipe (PVC pipe 19) are connected, and the propulsion process is performed in the same manner. In this case, the screw conveyor 17
Are connected by a universal joint (a cross joint or the like), and the casing short tube 1A is connected with the O-rings 7, 7 and the collar 5 and then the connecting portions 2, 3 are connected to the connecting pin 8 in a freely bendable manner.
The next PVC pipe 19 is also joined by the O-rings 21 and 21 and the collar 22.

In this way, the screw conveyor 1
7. Propulsion is performed while adding the casing short pipe 1A and the PVC pipe 19, and when reaching a place where the vehicle should bend, the direction correcting cylinders 26, 26,... Let it. If the cutting edge 25 is returned to the straight traveling state and propelled after being bent in a predetermined direction, the PVC pipe 19 is bent and advanced in the bent portion as shown in FIG.
Thus, the PVC pipe 19 can be embedded in a state where it is bent in a predetermined direction. Reference numeral 27 denotes the cutting edge 25 and the front pipe 2
The reaching shaft for collecting 4 etc. is shown.

The casing short pipe 1A,
The connection portion 1A is maintained in a sealed state by the collar 5 and the O-rings 7, 7, and the connection portion of the PVC pipes 19, 19 is also maintained by the collar 22 and the O-rings 21, 21.

FIG. 5 shows another modification of the connecting portion of the casing short tubes 1A, 1A.
Without a taper on the pipe end face, and replacing the seal with the O-rings 7, 7 and the collar 5 to make the casing short pipes 1A, 1
Both ends of the bellows 28 are externally fitted and fixed to the outer periphery of the tube end of A.

According to this embodiment, similarly to the above, the PVC pipe 1
Nine music embeddings can be performed.

[0031]

As described above, according to the present invention, it is possible to apply the present invention to bending and burying small-diameter pipes and low-yield pipes. It can be significantly reduced.

Further, since the casing short pipe can be bent by connecting it by bending it at an arbitrary angle, it is possible to cope with a sharp bend.

[Brief description of the drawings]

FIG. 1A is a view showing a state of burying a pipe according to an embodiment of the present invention, and FIG.

FIG. 2 is a plan view showing a cross section of a part of a connection portion of a curve propulsion casing according to the present invention.

FIG. 3 is a view taken in the direction of arrow A in FIG. 2;

FIG. 4 is an enlarged view of a main part of FIG. 2;

FIG. 5 is a plan view in which a part showing a modification of the present invention is a cross section.

FIG. 6 is a sectional view showing an example of a connection portion of a buried pipe (PVC pipe).

FIG. 7 is a half sectional view showing a conventional technique.

FIG. 8 is a view taken in the direction of arrow B in FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 1A Casing short pipe 2, 3 Connecting part 4 Tapered surface 5, 22 Collar 7, 21 Seal material (O-ring) 8 Connection pin 9 Propulsion device 10 Start-up pit 12 Propulsion device main body 13 Hydraulic cylinder for propulsion 17 Screw conveyor 19 Embedded Pipe (PVC pipe) 24 Conduit 25 Cutting edge 26 Direction correcting cylinder

Claims (3)

[Claims] 1. A casing through which a screw conveyor connected by a universal joint is inserted. The casing is formed by connecting casing short pipes, and connecting sections are provided at symmetrical positions on the diameter line of the pipe end of each casing short pipe. The connecting section is connected by a vertical axis so that the casing short pipe can pivot within a required angle range, and the outer periphery of the connecting section end of the casing short pipe is sealed with a sealing material. casing. 2. A collar which forms a tapered surface on both sides of the connecting portion of the pipe end surface of the casing short pipe, and wherein the sealing material is provided between the abutting portions of the casing short pipe and surrounds the outer periphery thereof. 2. The curve propulsion casing according to claim 1, comprising a flexible sealing material such as an O-ring interposed between an inner surface of the collar and an outer peripheral surface of the casing short tube. 3. The casing according to claim 1, wherein the sealing member is formed of a bellows extending between outer peripheral portions of pipe ends of the casing short pipe.