JP2804986B2 - Propulsion body for propulsion method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a propulsion head for connecting a plurality of propulsion pipes to each other to bend freely, and a propulsion head for excavating earth and sand to the tip of the propulsion pipes for bending. Comprising a tubular propulsion head body,
A drive shaft which is fitted to the propulsion head main body so as to be capable of driving rotation and driving in and out of the propulsion direction, and a leading conductor having a diameter larger than that of the drive shaft is attached to a tip of the drive shaft. It relates to a construction method propulsion body.

[0002]

2. Description of the Related Art Conventionally, in the above-described propulsion body for a propulsion method, the back surface of the leading conductor is formed in an uneven plane.

[0003]

However, according to the above-mentioned conventional configuration, the rear surface of the leading conductor is formed in an uneven plane. Is pushed to the front end side of the propulsion head body by the back part of the leading conductor, and as the leading conductor repeats withdrawing, the sediment becomes a large mass between the propelling head body and the leading conductor. The drawback is that the retraction of the drive shaft into the propulsion head body is prevented, and as a result, the stroke of the drive shaft is shortened, and in the worst case, the drive shaft cannot be expanded or contracted. SUMMARY OF THE INVENTION It is an object of the present invention to provide a propulsion body for a propulsion method in which the above-mentioned conventional disadvantages are solved and the drive shaft can be smoothly retracted into the propulsion head main body.

[0004]

The feature of the propulsion method propulsion body according to the present invention for achieving the above object is as follows: as the drive shaft retreats while being driven and rotated in the propulsion head main body, The projection for earth and sand scraping that scrapes out the earth and sand around the drive shaft is provided on the back surface of the leading conductor,
The operation and effect are as follows.

[0005]

[Operation] In other words, as the drive shaft retreats while being driven and rotated in the propulsion head main body, a sediment scraping projection for scraping out the earth and sand around the drive shaft is provided on the back surface of the leading conductor. Even if the tip conductor repeatedly moves out of the propulsion head body, as before, earth and sand around the drive shaft may remain between the back part of the tip conductor and the front end of the propulsion head body. As a result, the leading conductor can be smoothly retired into the propulsion head body.

[0006]

As described above, since the leading conductor can smoothly retreat into the propulsion head main body, a propulsion body for a propulsion method with good workability can be provided.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 3 and FIG. 4, a small-diameter (for example, an outer cylindrical surface-shaped propulsion head 1 and a plurality of outer cylindrical surface-shaped propulsion tubes 2), each of which has a cylindrical surface group, each outer surface of which is cylindrical. (Around 100mm or less)
The propulsion body for a propulsion method is constructed in such a way that the pipe group is bent and connected via a joint portion J so that the pipe group is propelled by a pushing device (not shown) while being bent in the soil. Have been.

The propulsion head 1 is fitted inside a tubular propulsion head body 1A such that the propulsion head 1 can be driven to rotate around the axis P along the longitudinal direction of the propulsion head body 1A and to be able to drive in and out of the propulsion direction. A piston portion 12 (an example of a drive shaft) is provided, and a leading conductor 3 having a diameter larger than that of the piston portion 12 is attached to the tip of the piston portion 12, and the leading conductor 3 is moved together with the piston portion 12 around the axis of the head main body 1A. And a telescopic mechanism 5 for operating the tip conductor 3 to move back and forth in the axial direction with respect to the head main body 1A. The leading conductor 3 is fitted into a cylindrical shaft 14 of a piston portion 12 of the leading conductor 3 and a rotating shaft 8 rotatably fitted inside the head main body 1A around an axis.
By being fitted to the cylinder portion 13 of the head main body 1A externally fitted to the piston portion 12, the head body 1A is supported by the head main body 1A so as to be relatively rotatable and relatively movable along the axial direction. The front part of the tip conductor 3 receives the earth pressure as the propulsion pipe 2 is propelled underground, and receives a pressure for turning the propulsion head 1 in a direction in which the earth pressure is received. A surface F is formed, and as shown in FIG. 1, FIG. 2, and FIG. 3, on the back surface portion 3A of the leading conductor 3, the piston portion 12 is driven into the propulsion head main body 1A and retreats while being driven. The earth and sand scraping projections 21 for scraping the earth and sand 20 around the piston portion 12 are provided at three places in the circumferential direction. Although not shown, a known sliding material discharging means for discharging a sliding material for reducing the frictional resistance between the earth and sand and the tube group is provided at the tip of the leading conductor 3.

The turning mechanism 4 includes a propulsion head body 1A.
Spiral groove 6 formed in a part of the inner peripheral surface of
And a spline shaft portion 8a meshing with a spline hole portion 7b formed on the inner surface side of the hydraulic piston 7 with a screwing convex portion 7a screwed into the hydraulic head 7A. Is supplied / discharged to / from a rotating shaft 8 formed on the outer peripheral portion and pressure receiving chambers 10 on both sides of the piston head 7c of the hydraulic piston 7, and the hydraulic piston 7 is reciprocated in the axial direction of the head main body 1A. A pair of pressure oil supply paths 9
A, 9B (see FIG. 4). Inside the rotating shaft 8, apart from the two hydraulic pipes constituting the pressure oil supply passages 9A and 9B, there are formed supply / discharge passages 11 of the pressure oil to the expansion / contraction mechanism 5, which will be described later. The supply / discharge passage 11 and the hydraulic piping are both guided to the rear propulsion pipe 2 via the joint J. In the rotating mechanism 4 configured as described above, the pressurized oil is supplied from the one pressurized oil supply passage 9A (or 9B) to the propulsion head body 1A, and the propelled oil is supplied to the other pressurized oil supply passage 9B (or 9A). When the hydraulic oil is returned from the head main body 1A, the hydraulic piston 7 reciprocates. With this movement, the hydraulic piston 7 that has the screwing convex portion 7a screwed into the spiral groove 6 of the head main body 1A becomes positive. It rotates in the opposite direction, and the rotation shaft 8 rotates in the forward and reverse directions following the rotation, and further, the leading conductor 3 is driven to rotate about the axis P in accordance with the rotation. Note that the tip conductor 3 has at least 36
It is designed to rotate 0 degrees or more.

The telescoping mechanism 5 is a bottomed cylindrical piston unit integrally formed with the leading conductor 3 so as to be slidably fitted to the rotating shaft 8 of the rotating mechanism 4 in the axial direction. 12
And a pressure for supplying pressure oil to a cylinder portion 13 of the head main body 1 </ b> A containing the piston portion and a supply / discharge passage 11 formed in the rotation shaft 8 to the internal space of the cylinder portion 13. And a fluid supply device (not shown). The telescopic mechanism 5 is provided with pressure receiving surfaces 12a and 14a on both the bottom of the cylindrical hole of the piston portion 12 and the rear end surface in the traveling direction of the piston portion 12, respectively.
Pressure chamber 1 between the end surface and the inner surface of cylinder portion 13
5 and 16 are formed. And, the two pressure chambers 15,
For 16, a communication passage 17 is provided to allow the flow of the pressure fluid from the pressure fluid supply device side. That is, the spline portion 8b formed on the outer peripheral surface of the rotation shaft 8 and the outer peripheral surface on the rear side in the propulsion direction from the place where the spline portion 8b is formed are formed in the cylindrical hole 14 of the piston portion 12.
The communication path 17 is formed slightly larger so as to form a gap that allows the flow of pressure oil.
Is composed. The telescopic mechanism 5 has the pressure chambers 15 and 16 only on the side where the leading conductor 3 is pushed out, and the pushing force of the subsequent propulsion pipe 2 moves in the direction in which the leading conductor 3 is pulled into the cylinder portion 13. It is configured to do so.

When the tube group is made to travel straight by using the propulsion body having the above structure, the hydraulic piston 7 is reciprocated by continuously sucking and discharging the pressure oil through the pressure oil supply passages 9A and 9B.
The reciprocating movement pushes the propulsion pipe 2 while rotating the rotation shaft 8, that is, the leading conductor 3. In addition, the piston part 1
2 retreats while being driven and rotated into the propulsion head body 1A, the earth and sand 20 around the piston portion 12 is scraped out by the sediment scraping-out projections 21, and the leading conductor 3 moves out of the propulsion head body 1A. Is repeated, the earth and sand around the drive shaft do not remain between the back surface 3A of the leading conductor and the end of the propulsion head body 1A. When the direction is corrected using the propulsion body, the propulsion pipe 2 is pushed in with the pressure receiving surface F facing the side opposite to the side to be turned without rotating the tip conductor 3 as described above. Go. Then, the propulsion direction of the propulsion head 1 is turned in the opposite direction to the pressure receiving surface F by receiving the earth pressure on the pressure receiving surface F, and the propulsion head 1 turns.

[Another embodiment] The projection 21 for scraping out the earth and sand
Is not limited to three, and three or less or three or more may be formed.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is a side view showing a distal end side of a propulsion head of a propulsion body.

FIG. 2 is a front view of the back portion of the tip conductor.

FIG. 3 is a sectional view of a propulsion head of the propulsion body.

FIG. 4 is a sectional view of a propulsion pipe and a propulsion head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Propulsion head 1 Head main body 2 Propulsion pipe 3 Lead conductor 3A Back part of lead conductor 12 Drive shaft 20 Earth and sand 21 Projection for earth and sand scraping

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Takashi Togawa 1-1-1, Hama, Amagasaki-shi, Hyogo Inside Kubota Technology Development Laboratory Co., Ltd. (58) Field surveyed (Int. Cl. ⁶ , DB name) E21D 9 / 06 311

Claims (1)

(57) [Claims] 1. A plurality of propulsion tubes (2) are flexibly connected to each other, and a propulsion head (1) for excavating earth and sand is flexibly connected to a tip propulsion tube (2). To form the propulsion head (1), a tubular propulsion head main body (1A) and a drive shaft internally fitted to the propulsion head main body (1A) so as to be driven to rotate and protrude and retreat in the propulsion direction. (12), and a propulsion body for a propulsion method, wherein a tip conductor (3) having a larger diameter than the drive shaft (12) is attached to a tip of the drive shaft (12). )
Retreats while driving and rotating in the propulsion head body (1A), the earth and sand (2) around the drive shaft (12).
A propulsion body for a propulsion method, wherein a projection (21) for scraping out earth and sand that scrapes out (0) is provided on the back surface (3A) of the tip conductor (3).