JP3497705B2 - Flexible connection pipe - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible connecting pipe used for a diameter-expansion retracting device or the like when laying a cable laying pipe, a water and sewer pipe, a gas pipe, etc. in soil without cutting. . That is, when the pilot pipe laid in the first step of the pipe propulsion method is used as a guide and the propulsion pipe is laid in the second step in the direction opposite to the laying direction of the pilot pipe by the diametric expansion retractor, the pilot pipe and the diametrical retractor are installed. To a connecting pipe suitable for connecting to.

[0002]

2. Description of the Related Art FIGS. 7 and 8 show an example of a pipe laying procedure by a small diameter propulsion method. FIG. 7 shows a step of laying the pilot pipe C from the starting shaft A to the reaching shaft B as the first process. The former pushing device D is installed in the launch stand A, the outer cylinder E1 of the tip device E is extended, and the tip head E2 is perforated in the soil (FIG. 7A). Next, the cylinder of the original pushing device D is extended, and the tip device E and the pilot pipe C are press-fitted by a length corresponding to the digging length of the tip device E while contracting the tip device E (FIG. 7B). Then, by repeatedly performing the perforation and the press-fitting, the pilot pipes C are sequentially added and propelled into the soil. In that case, the tip head E2 is appropriately controlled in direction to lay the pilot pipe C while correcting the deviation in the propulsion direction (FIG. 7C). When the pilot pipe C reaches the reaching shaft B, the tip device E is removed from the reaching shaft B (Fig. 7).
D).

Next, as shown in FIG. 8, as a second step, a propulsion pipe F having a diameter larger than that of the pilot pipe C is laid from the reaching shaft B to the starting shaft A. First, the diameter-expansion retractor G is attached to the leading pilot pipe C (FIG. 8A).

The expansion retraction device G comprises a piston rod G2 which is extended by a single-acting hydraulic cylinder G1.
A pilot pipe C is connected to the tip of G2, and a propulsion pipe F is connected to the rear of the diameter expansion and retraction device G.

Hydraulic oil is supplied from a hydraulic pump on the ground to a single-acting hydraulic cylinder G1 of the radial expansion device G, and a piston rod G2 is supplied.
Extend the soil to dug the soil. The hydraulic oil is supplied from the starting shaft A through the pilot pipe C to the piston cylinder G2.
Via hydraulic hose G4 connected to oil passage G3.
Next, the diametrical expansion retractor G is retracted by the former pushing device D by the former pushing device D using the pilot pipe C as a guide, and the propulsion pipe F connected to the diametrical expansion retractor G is sequentially retracted into the soil. The tipping and the retraction are repeated until the propulsion pipe F is added to reach the starting shaft A.
At this time, in the starting shaft A, the pilot pipe C is sequentially removed and collected by a length corresponding to the retracted length of the propulsion pipe F.

[0006]

However, when the propulsion pipe is pulled in the second step, there is the following problem due to the influence of the installed state of the pilot pipe. Direction control is performed when laying the pilot pipe in the first process, but the laying condition of the pilot pipe is not always linear,
It may be curved. In the second step, the propulsion pipe is pulled in using this pilot pipe as a guide, so if the pilot pipe is installed in a curved state, the expansion retraction device cannot follow this curvature and the operating resistance of the single-acting hydraulic cylinder becomes large. It may be sluggish or may not work at all. This is because the hydraulic cylinder itself has a linear motion structure, so that if the pilot pipe is installed in a curved state, a force in the bending direction acts on the piston rod.

[0007]

In order to solve the above-mentioned problems, the present invention interposes a bendable connecting pipe in the connection between the pilot pipe and the diametrical expansion retractor. That is, the present invention is a hollow-cylindrical flexible connection pipe that connects one connection target and the other connection target, and a spherical receiving member having a connecting device with the one connecting target, and this spherical receiving member. And a spherical shaft that is flexibly fitted to and has a connecting tool with the other connection target.

Here, in order to suppress the relative rotation between the spherical receiving member and the spherical axis, the spherical receiving member has an inner spherical surface portion and a shaft hole portion integrated with the inner spherical surface portion. An outer spherical surface portion that fits into the inner spherical surface portion, and a shaft portion that is inserted into the shaft hole portion integrally with the outer spherical surface portion, and the cross-sectional shapes of the shaft hole portion and the shaft portion are polygonal. Is desirable.

In this case, the opposite side dimension of the shaft hole portion is larger than the opposite side dimension of the shaft portion, but is preferably smaller than the diagonal dimension of the shaft portion.

Further, it is preferable to provide an elastic dust seal that prevents foreign matter from entering the fitting portion between the spherical receiving member and the spherical shaft.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. 1 is a sectional view of the connecting pipe of the present invention in a straight state, and FIG. 2 is a sectional view of the connecting pipe in a bent state.

The connecting pipe 1 according to the present invention comprises a pilot pipe C (one of the connecting targets) and a piston rod G2 in the expanding device.
It is interposed between the tip end (the other connection target) and is configured to be bendable by including the spherical receiving member 2 and the spherical shaft 3.

The spherical receiving member 2 has a substantially hollow cylindrical shape,
The outer circumference is formed in a polygonal shape, and has an inner spherical surface 2-1 having an inner spherical surface on the inner circumference and a shaft hole 2-2 having a cylindrical surface on the inner circumference integrally with the inner spherical surface 2-1. . On the other hand, the spherical shaft 3 is also of a substantially hollow cylindrical shape, and has an outer spherical surface 3-1 provided at one end and a shaft 3-2 having a polygonal outer periphery continuous with the outer spherical surface 3-1. Equipped. Then, the outer spherical surface portion 3-1 is fitted to the inner spherical surface portion 2-1, and the shaft portion 3-2 is inserted into the shaft hole portion 2-2, so that both spherical surface portions 2-1 and 3-1 The spherical shaft 3 can be bent with respect to the spherical receiving member 2 by sliding (see FIG. 2).

Here, both ends of the connecting pipe 1 are provided with tapered pipes for reducing resistance when traveling through the soil. On the pilot pipe side of the connecting pipe 1, there is a front taper pipe 4 which is externally fitted to the spherical receiving member 2, and on the piston rod side, the shaft portion 3- of the spherical shaft.
A rear taper pipe 5 is fitted on the outside of the pipe 2. Then, the connecting pipe 1 and the piston rod G2 or the pilot pipe C
The front connection tool 6 and the rear connection tool 7 were used for the connection with.

The front connector 6 has a male screw 6-1 at one end,
It has a cylindrical shape with an inner peripheral projection 6-2 at the other end. The spherical receiving member 2 and the pilot pipe C are connected to each other via the tightening nut 8 and the front taper pipe 4. Inner peripheral projection of tightening nut 8
8-1 engage with the outer peripheral projection 2-3 of the spherical receiver, and tighten the female screw 8-2 of the tightening nut with the male screw 4-1 at one end of the front taper pipe.
It is screwed in and joined. Furthermore, the inner peripheral projection 6- of the front connecting tool
2 is engaged with the outer peripheral groove 4-2 at the other end of the front taper pipe,
The pilot pipe C is connected from the spherical receiving member 2 by screwing the female screw at the tip of the pilot pipe into the male screw 6-1 of the front connecting device.

AA of FIG. 1 in such a connecting structure
An arrow view is shown in FIG. The spherical receiver 2 has a polygonal outer shape,
Since the inner peripheral shape of the front taper pipe 4 that is closely fitted to the outer periphery of the front taper pipe 4 is also polygonal, the front taper pipe 4 does not rotate with respect to the spherical receiving member 2. On the other hand, the front taper pipe 4 and the front connector 6 are connected to the outer peripheral groove as described above with reference to FIG.
4-2 and the inner peripheral projection 6-2 are connected by the engagement,
6 is configured to be rotatable.

The rear connecting member 7 is of a cylindrical shape having an internal thread 7-1 at one end and an inner peripheral projection 7-2 at the other end. The connection between the spherical shaft 3 and the piston rod G3 is an inner peripheral projection.
7-2 engage the outer peripheral groove 3-3 of the shaft 3-2, and
Screw the male screw at the end of the piston rod into 7-1.
Then, the spherical shaft 3 and the rear connecting member 7 are connected by the engagement of the outer peripheral groove 3-3 and the inner peripheral protrusion 7-2, and both 3 and 7 are configured to be rotatable.

A hydraulic hose G4 for supplying hydraulic oil to the diameter expanding and retracting device is inserted into the inside of the connecting pipe 1. This hydraulic hose G4 is introduced from the ground into the connection part through the starting shaft and the pilot pipe, and the piston rod G2 is inserted through the connector.
Connected to oilway G3.

By coupling the spherical receiving member 2 and the spherical shaft 3 as described above, relative rotation between the spherical receiving member 2 and the spherical shaft 3 is suppressed, and the hydraulic hose G4 is twisted and cut. Can be prevented. This rotation stopping mechanism will be described with reference to FIGS. 4 is a view taken along the line BB in FIG. 1, and FIG.
FIG. 5A is a sectional view showing a state where the spherical axis is rotated to the left from the state of FIG. 4, and FIG. 5B is a sectional view showing a state where the spherical axis is rotated to the right from the state of FIG.

As shown in FIG. 4, the spherical hole 2 of the spherical receiver is shown.
The cross-sectional shape of 2 and the cross-sectional shape of the shaft portion 3-2 of the spherical axis are polygonal and similar shapes. In this example, the shape is a regular octagon. Here, when the diagonal dimension of the shaft hole portion 2-2 is H, the diagonal dimension is I, the diagonal dimension of the shaft portion 3-2 is J, and the diagonal dimension is K, these are in the relationship of the following equation. . H>J>I> K Therefore, even if the spherical receiving member 2 and the spherical shaft 3 are relatively rotated, as shown in FIG. 5, the corner portion of the shaft portion 3-2 has the shaft hole portion 2-. The rotation is stopped when it comes into contact with the inner peripheral surface of 2. Thereby, the rotation of the spherical receiving member 2 and the spherical shaft 3 in the connecting pipe 1 is suppressed, and the twisting of the hydraulic hose G4 (Figs. 1 and 2) is prevented.

Of course, even if this rotation stopping mechanism is provided, there is no influence on the above-described bending mechanism of the spherical receiving member and the spherical shaft. FIG. 6 shows a view taken along the line CC in FIG. Figure 6
As shown in, even if the spherical shaft 3 is bent with respect to the spherical receiving member 2, the shaft portion 3-2 is eccentric to the shaft hole portion 2-2,
The spherical receiving member 2 and the spherical shaft 3 can be bent within the range of the difference between the diagonal dimension H of 2-2 and the diagonal dimension J of the shaft portion 3-2.

In the present example, a dust seal 9 is provided at the fitting portion between the spherical receiving member 2 and the spherical shaft 3 to prevent foreign matter such as earth and sand from entering (see FIGS. 1 and 2). The dust seal 9 has an annular shape as a whole and a convex cross-section, and is made of an elastic material such as rubber so that it can be deformed following the bending of the spherical receiving member 3 and the spherical shaft 2. . Here, a dust seal 9 is interposed in the space surrounded by the rear taper pipe 5, the tightening nut 8 and the spherical receiving member 2 on the outer periphery of the shaft portion 3-2.

With the connecting pipe having such a structure, when the piston rod of the diametrical expansion retractor and the pilot pipe are connected, the connecting portion itself bends, so that the diametrical expansion device follows the bent installation state of the pilot pipe. Can be made. In that case, it is possible to suppress the excessive bending stress applied to the piston rod. Further, by preventing relative rotation between the spherical receiving member and the spherical shaft, the hydraulic hose that supplies the hydraulic oil to the diameter expansion and retracting device through the inside of the connecting portion is not twisted and cut.

[0024]

As described above, since the connecting pipe of the present invention has a bending function, it can be expanded even if the pilot pipe is installed in a curved state when it is used for connecting the pilot pipe and the diameter expansion and retracting device. The diameter retractor can be made to follow. In particular, by providing the rotation stopping mechanism at the connection portion, it is possible to prevent the hydraulic hose that supplies the hydraulic oil to the expanded diameter retractor from being broken.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a connecting pipe of the present invention in a straight state.

FIG. 2 is a cross-sectional view of the connecting pipe of the present invention in a bent state.

FIG. 3 is a view taken along the line AA in FIG.

FIG. 4 is a view taken along the line BB in FIG.

5A is a cross-sectional view showing a state where the spherical axis is rotated to the left from the state of FIG. 4, and FIG. 5B is a cross-sectional view showing a state where the spherical axis is rotated to the right from the state of FIG. is there.

FIG. 6 is a view on arrow CC in FIG.

FIG. 7 is an explanatory view of the first process using the tip device for pipe propulsion in the pipe laying process of the compaction-free soil-removal method, where (A) is when the tip device is extended, (B) is when the original pushing device is extended, C) shows the direction control of the tip device, and (D) shows the completion of the pilot pipe installation.

FIG. 8 is an explanatory view of a second step using the diameter expanding and retracting device in the pipe laying process of the compaction-free soil discharging method, (A) when the diameter expanding and retracting device is installed, and (B) when the diameter expanding and retracting device is retracted. , (C) shows the tip of the diameter expansion retractor, and (D) shows the diameter expansion actuator retracted.

[Explanation of symbols]

1 Connection tube 2 Spherical bracket 2-1 Inner spherical surface 2-2 Shaft hole 2-3 Outer peripheral projection 3 Spherical shaft 3-1 Outer spherical surface 3-2 Shaft 3-3 Outer peripheral groove 4
Front taper pipe 4-1 Male screw 4-2 Outer peripheral groove 5 Rear taper pipe 6 Front connector 6-1 Male screw 6-2 Inner peripheral protrusion 7 Rear connector 7-1 Female screw 7-2 Inner peripheral protrusion 8 Tightening nut 9 Dust seal A Starting shaft B Reaching shaft C
Pilot pipe E Tip device E1 Outer cylinder E2 Tip head F Propulsion tube G Expansion retractor G1 Single acting hydraulic cylinder G2 Piston rod G3 Oil passage
G4 hydraulic hose

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Akio Takashi 1 Taya-cho, Sakae-ku, Yokohama Sumitomo Electric Industries, Ltd. Yokohama Works (72) Inventor Hiroshi Irie 3-19-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Nihon Telegraph and Telephone Corporation (72) Inventor Akira Sawaguchi 3-19-2 Nishishinjuku, Shinjuku-ku, Tokyo Japan Telegraph and Telephone Corporation (72) Inventor Junichi Shirakawa 3-18-10 Moto-Asakusa, Taito-ku, Tokyo Inside Airek Giken Co., Ltd. (72) Inventor Kimihiro Maeda 3-18-10 Motoasakusa, Taito-ku, Tokyo Inside Airek Giken Co., Ltd. (56) Bibliography 4-22588 (JP, U) ( 58) Fields investigated (Int.Cl. ⁷ , DB name) E21D 9/06 E21D 9/08

Claims (3)

(57) [Claims] 1. A hollow cylindrical flexible connection tube connecting the one connection object and the other connection object, the connector of said one of the connection object, and a spherical receptacle leading to this connector, a spherical shaft Ru fitted freely bent the spherical receptacle, and a connector with the other connection object connected to the spherical shaft
The spherical receiving member includes an inner spherical surface portion and an axial hole integrated with the inner spherical surface portion.
And a spherical axis having an outer spherical portion fitted to the inner spherical portion and an outer spherical portion
A shaft part that is inserted into the shaft hole part integrally with the spherical part, and the cross-sectional shapes of the shaft hole part and the shaft part are polygonal.
To prevent relative rotation between the spherical support and the spherical axis.
A flexible connection tube characterized by being configured into . 2. The opposite side dimension of the shaft hole section is different from the opposite side dimension of the shaft section.
The flexible connection pipe according to claim 1, wherein the flexible connection pipe is larger than the diagonal portion but smaller than a diagonal dimension of the shaft portion . 3. A foreign matter is caught in a fitting portion between the spherical surface receiving member and the spherical shaft.
Equipped with an elastic dust seal to prevent entry
The flexible connection pipe according to claim 1, wherein