JPH1181858A - Small bore pusher - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a bore of a roughly similar diameter to an outer diameter of a buried pipe, push the buried pipe without deteriorating construction efficiency even with a conglomerate bed or soil quality of a high N-value, return a head pipe to a starting vertical shaft, and install the head pipe to an original position after returning the head pipe for enabling pushing or a long distance. SOLUTION: An outer diameter of a head pipe is smaller than an inner diameter of a buried pipe, it can be parted to a front drum and a back drum 4b, and the front drum and the back drum 4b are connected to each other by an oscillation jack 9. An outer diameter of a cutter head 7 provided on a tip of the front drum is smaller than the inner diameter of the buried pipe, and the front drum is oscillated by the oscillation jack 9 in such a way that an outer diameter of a bored track is roughly similar to an outer diameter of the buried pipe. The head pipe and the cutter head 7 are recovered through the buried pipe into a starting vertical shaft.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small-diameter thruster for laying a buried pipe underground.

[0002]

2. Description of the Related Art Conventionally, as a tunnel machine for laying pipes such as sewer pipes, electric wires or communication lines underground,
Mainly small caliber thrusters are used. When laying the pipeline using a small-diameter thruster of this type, a start shaft and an arrival shaft are constructed on a predetermined line on which the pipeline is to be laid, and the start shaft is provided with a small-diameter thruster. A main pushing device is installed. The leading pipe of this small-diameter thruster is propelled from the starting shaft through a pipe following the leading pipe by a main pushing device while rotating a cutter head provided at the tip thereof. In this way, a plurality of tubes follow the leading conduit until the leading conduit reaches the reaching shaft pre-established on the planned laying line, and is composed of a plurality of tubes between the starting shaft and the reaching shaft. Pipelines can be laid.
If the direction of the leading conduit deviates from the planned laying line during propulsion, the direction is controlled by the direction correcting device. After the propulsion, the leading conduit is removed from the reaching shaft.

[0003] The leading conduit is constituted by a device such as a rotary drive unit of a cutter head, a direction correcting device for controlling the direction, an earth discharging device and a position measuring device. Further, the pipe to be buried is succeeded so as to directly or indirectly contact the rear end of the leading pipe, and the buried pipe is contacted with the main pushing device and propelled to form a continuous buried pipe. It is configured to transmit thrust to the leading conduit via the same.

However, in such a small-diameter thruster, the starting shaft and the reaching shaft are indispensable. Therefore, when the reaching shaft cannot be constructed due to the circumstances around the place where the burial tube is laid, the buried tube is not used. There is a problem that it cannot be laid.

As a method for solving such a problem,
In Japanese Utility Model Laid-Open Nos. 4-108682 and 4-108689 proposed by the present applicant, the outer diameter of the leading pipe is made smaller than the inner diameter of the buried pipe, and the leading pipe is collected in the starting shaft through the buried pipe. A small-diameter pipe propulsion device is disclosed.

Japanese Unexamined Patent Publication (Kokai) No. 9-144485 discloses an excavator in which a cutter head is constituted by a plurality of refractible spokes arranged in a radial direction, and an outer peripheral bit is attached to a tip of the spoke. Have been. The length of the spoke is set so that the locus of the outer peripheral bit when the cutter head is rotated is substantially equal to or larger than the outer diameter of the outer cylinder. This excavator is configured to bend the spokes after excavation to avoid interference with the pipe, and to return to the starting shaft through the inside of the pipe.

[0007]

However, Japanese Utility Model Laid-Open No. 4-108682 and Japanese Utility Model Laid-Open No. 4-108689.
In the small-diameter pipe propulsion device disclosed in Japanese Unexamined Patent Publication, since the outer diameter of the leading pipe is smaller than the inner diameter of the buried pipe, the portion outside the inner diameter of the buried pipe is propelled without excavating. As a result, there is a problem that the ground outside the inner diameter of the buried pipe becomes compacted, the propulsion resistance increases, and the construction efficiency decreases. In addition, there is a problem that the propulsion resistance is excessively great when propelling in soil having a high N value, and is not suitable for long-distance propulsion.

In the excavator disclosed in Japanese Patent Application Laid-Open No. 9-144485, since the cutter head is formed of refractible spokes, it is difficult to excavate on the soil having a high N value as described above. There is a problem that it is not suitable for excavation of the reticulate layer and that the structure of the cutter head is very complicated. There is also a problem that the direction is difficult to correct because the spokes are refracted when the direction is corrected.

The present invention has been made in order to solve such a problem, and the present invention excavates a diameter substantially equal to the outer diameter of a buried pipe, and is capable of constructing an excavated pipe even in the case of a rocky layer or a soil having a high N value. The buried pipe can be propelled without reducing the efficiency, the leading pipe and cutter head can be pulled back to the starting shaft, and the previously recovered leading pipe and cutter head can be installed at the position before collection. It is an object of the present invention to provide a small-diameter thruster capable of long-distance propulsion.

[0010]

The small-diameter propulsion device according to the present invention has the following features.
A front pipe having an outer diameter smaller than the inner diameter of a buried pipe buried in the ground and divided into a front trunk and a rear trunk, and a cutter having an outer diameter smaller than the inner diameter of the buried pipe provided at the front trunk tip of the front pipe. A small-diameter thruster having a head, wherein the front body and the rear body are connected by a jack, and the front body is swung by expansion and contraction of the jack, and the outer diameter of the buried pipe is substantially the same as the outer diameter of the buried pipe by the cutter head. Alternatively, the excavation is performed with a slightly larger excavation diameter.

In the present invention, the front trunk and the rear trunk of the front conduit having an outer diameter smaller than the inner diameter of the buried pipe are connected by a jack, and the front trunk is rocked by the expansion and contraction of the jack. The excavation diameter of the cutter head attached to the trunk end is configured to be substantially the same as or slightly larger than the outer diameter of the buried pipe. The outer diameter of the cutter head is smaller than the inner diameter of the buried pipe.

The small-diameter thruster constructed as described above is installed in a starting shaft previously constructed on a planned laying line of a buried pipe, and the cutter head is rotated by the jack from the starting shaft while the cutter head is rotated. The body is rocked, and the cutter head excavates a diameter substantially equal to or slightly larger than the outer diameter of the buried pipe. Next, the buried pipe and the leading conduit are propelled such that the buried pipes are successively added.

After the buried pipe is laid to the predetermined length and the propulsion is completed, the center axis of the cutter head and the center axis of the buried pipe are aligned, and the front pipe and the cutter head are pulled back to the starting shaft. Recover to the starting shaft via the buried pipe.

In the present invention, the front body is swung by the jack while rotating the cutter head, so that a diameter substantially equal to or slightly larger than the outer diameter of the buried pipe can be excavated, thereby increasing the propulsion resistance. Since the buried pipe can be propelled without the need, there is an effect that the applicable soil quality is wide. Further, since the outer diameters of the leading pipe and the cutter head are smaller than the inner diameter of the buried pipe, the leading pipe can be smoothly recovered to the starting shaft through the buried pipe. For this reason, it is possible to recover the leading conduit on which the expensive device is mounted without the need for the reaching shaft, and thus there is an effect that the construction cost can be extremely reduced.

In the present invention, the leading pipe and the cutter head can be pulled back to the starting shaft before the buried pipe to be laid reaches the predetermined length, as described above.
In this way, the leading pipe and the cutter head are collected in the starting shaft, and the disk cutter in front of the cutter head is inspected or replaced. Thereafter, the leading pipe and the cutter head are mounted at a position before being collected, and thrust is applied again to lay the buried pipe. Thus, there is an effect that long-distance propulsion becomes possible without providing an intermediate shaft. There is an effect that the number of shafts can be reduced as compared with the related art, and the construction cost can be extremely reduced.

In the present invention, on the outer periphery of the leading conduit,
It is preferable to provide an outer cylinder whose outer diameter is substantially the same as the outer diameter of the buried pipe. By doing so, the front body can be easily rocked even on the soil layer where the skin easily falls off, and the effect of preventing earth and sand from entering between the front body and the rear body can be prevented. To play.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a specific embodiment of a small-diameter thruster according to the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a small-diameter thruster according to an embodiment of the present invention, FIG. 2 is a side view of a swinging jack, and FIG. A sectional view taken along line A is shown.

The small-diameter thruster 1 of this embodiment comprises an outer cylinder 3 having an outer diameter substantially the same as the outer diameter of the buried pipe 2 and a leading pipe 4 having an outer diameter smaller than the inner diameter of the buried pipe 2. ing. The front conduit 4 is divided into a front trunk 4a and a rear trunk 4b, and an earth discharging device 5 composed of a screw conveyor extends at the tunnel axis inside the front conduit 4. A cutter head 7 having a plurality of disk cutters 6 is provided at the front end of the front conduit 4 on the front surface. The cutter head 7 is fastened to a rotation driving unit 8 inside the front conduit 4 so as to be rotatable, and has an outer diameter smaller than the inner diameter of the buried pipe and is disposed on the tip side from the outer cylinder 3. It is configured. Further, the front trunk 4a and the rear trunk 4
b are connected by four swinging jacks 9 (FIG. 2), and the front body 4a is moved by the swinging jacks 9 to the rear body 4b.
Rocked against. In addition, the discharging device 5 is provided with a bent portion 5a corresponding to the division position of the front trunk 4a and the rear trunk 4b so as to swing in accordance with the swing of the front conduit 4. In addition, an earth and sand seal 3 a is provided at a tip between the tip conduit 4 and the outer cylinder 3. A vertical rib (rolling stopper) is provided on the side surface of the swing jack 9 on the side of the rear trunk 4b.
(Not shown) is provided to prevent the rotation of the cutter head 7 from being transmitted to the front trunk 4a when the cutter head 7 is rotated by this vertical rib, thereby preventing the front trunk 4a from rotating with respect to the rear trunk 4b. Has been.

Further, a thrust transmitting member 10 is provided at the rear end side of the front conduit 4, and this thrust transmitting member 10 is provided at a plurality of positions at the front end of the buried pipe 2 and the rear end of the front conduit 4 (rear trunk 4b). Bolt 11. At the rear end (starting shaft) of the buried pipe 2, a main pushing device (not shown) is installed, and the thrust transmitting member 10 receives the thrust given from the main pushing device via the buried pipe 2. The power is transmitted to the outer cylinder 3 and the leading conduit 4. Further, as shown in FIG. 3, the thrust transmitting member 10 has a ring-shaped division structure that is smaller than the inner diameter of the buried pipe 2 and that can be divided in the circumferential direction. Further, a plurality of swing reaction force receiving members 12 that are in contact with the rear trunk 4b of the front conduit 4 are provided inside the outer cylinder 3. As shown in the sectional view taken along the line BB of FIG. 1 in FIG.
And the disk cutter 6 is arranged so as not to interfere when the cutter head 7 is pulled back.

In the small-diameter thruster 1 constructed as described above, first, the cutter head 7 is aligned with the center axis of the outer cylinder 3 as shown in FIG. While rotating the head 7, the center of the cutter head 7 is shifted upward by controlling the amount of expansion and contraction of the four rocking jacks 9 (FIG. 5B). Is substantially equal to the outer diameter of the outer cylinder 3. Thus, as shown in FIG. 6, a schematic diagram of the relationship between the amount of extension of the swing jack 9 and the swing rotation position (1/4 rotation) of the cutter head 7 (the disk cutter 6 is not shown) is shown. The extension amount of the cutter head 9 is adjusted, and the center axis of the cutter head 7 is gradually shifted in the swing rotation direction so as to swing so that the center of the cutter head 7 rotates around the center axis of the outer cylinder 3. By excavating the cutter head 7 in such a manner that the center axis of the cutter head 7 is shifted, the outermost periphery of the excavation trajectory of the cutter head 7 is made substantially the same as or slightly larger than the outer periphery of the outer cylinder 3.

As described above, the outer cylinder 3 is controlled by the cutter head 7.
A tunnel of approximately the same diameter as the outer diameter of the
The outer cylinder 3 is propelled by the thrust transmission device 10 by obtaining a propulsion reaction force. Next, a new buried pipe 2 is added to the rear end of the buried pipe 2. Thus, the above-described operation is repeated to the propulsion position of the small-diameter excavator 1, and the buried pipe 2 is laid.

After the propulsion operation by the small-diameter thruster 1 is completed, the swinging jack 9 is all contracted so that the center axis of the cutter head 7 and the center axis of the outer cylinder 3 coincide (FIG. 5).
(A)). On the other hand, the thrust transmission device 10 includes a bolt 11
Is removed, disassembled to be smaller than the inner diameter of the buried pipe 2, and collected into the starting shaft. Thereafter, the leading pipe 4 becomes independent from the buried pipe 2 and the outer cylinder 3, and the main body of the leading pipe 4 (including a device inside the leading pipe 4 such as the earth removal device 5) and the cutter head 7 are pulled back. At this time, since the disk cutter 6 on the front face of the cutter head 7 is arranged so as not to interfere with the swing reaction force receiving member 12 as described above (FIG. 4), the main body of the front conduit 4 and the cutter head 7 is smoothly recovered through the outer cylinder 3 and the buried pipe 2 to the starting shaft.

Accordingly, even if a reaching shaft is not required, many devices such as the rotary drive unit 8, the oscillating jack 9 and the earth discharging device 5 in the front conduit 4 and the cutter head 7 can be collected, so that the cost can be reduced. This has the effect that it can be achieved. Further, since the outer diameter of the cutter head 7 is substantially the same as the outer diameter of the outer cylinder 3, the buried pipe 2 and the outer cylinder 3 can be easily propelled even if the soil has a high N value, The effect is that the applied soil is wide.

In this embodiment, after the propulsion, the leading pipe 4 is pulled back. However, even during the propulsion, the leading pipe 4 and the cutter head 7 can be pulled back to the starting shaft. When the leading pipe 4 and the cutter head 7 are collected in the starting shaft during the propulsion, the disk cutter 6 on the front surface of the cutter head 7 is inspected or replaced in the starting shaft, and then the leading pipe 4 and the cutter head 7 are collected. Head 7
And the thrust transmitting device 10 is mounted at a position before being collected, and the propulsion operation is performed again. Thus, since the wear of the disk cutter 6 can be avoided, there is an effect that long-distance propulsion can be performed without providing an intermediate shaft.

In this embodiment, four rocking jacks 9
Is used, but the present invention is not limited to this, and any number may be used as long as the swing power and swing amount are sufficient.

In this embodiment, the swing reaction force receiving member 12
Are provided three per lap, but not limited to this,
It is sufficient if at least two are provided. However, it is necessary to arrange the reaction force receiving member 12 so as not to interfere with the disk cutter 6 when the front conduit 4 is pulled back.

In this embodiment, the outer cylinder 3 is provided, but the outer cylinder 3 may not be provided if the front conduit 4 such as a hard rock layer is a rockable stratum.

FIG. 7 is a schematic perspective view of a small-diameter thruster according to another embodiment of the present invention. In the small-diameter thruster 21 of this embodiment, four lattice jacks (oscillation means) 22 are provided between the front trunk 4a and the rear trunk 4b of the front conduit 4 so as to form a parallel link structure. . The other structure is the same as that of the present embodiment, and will not be described. The extension amount of the lattice jack 22 is controlled in the same manner as in FIG.
Front body 4a so as to be substantially the same as or slightly larger than the outer diameter of
Can be swung. Therefore, the same operation and effect as the above embodiment can be obtained. Furthermore, by using the parallel link structure, the rotation of the front body with respect to the rear body can be suppressed, so that a rolling stopper is not required and the structure is simplified, and the swinging of the front body 4a can be performed easily and accurately. There is also an effect that control can be performed.

In the present embodiment, the lattice jack 22 having four parallel link structures is used. However, the present invention is not limited to this.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a small-diameter thruster according to an embodiment of the present invention.

FIG. 2 is a side view of the swing jack according to the embodiment.

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is a sectional view taken along line BB of FIG. 1;

FIG. 5 is a front view (a) of the cutter head before swinging according to the present embodiment and a front view (b) of the cutter head when swinging upward.

FIG. 6 is a schematic diagram showing the relationship between the amount of extension of the swing jack and the swing rotation position of the cutter head according to the present embodiment.

FIG. 7 is a schematic perspective view of another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Small-diameter propulsion machine 2 Buried pipe 3 Outer cylinder 4 Front pipe 4a Front trunk 4b Rear trunk 5 Discharge device 5a Bending part 6 Disk cutter 7 Cutter head 8 Rotation drive part 9 Rocking jack 10 Thrust transmitting member 11 Bolt 12 Rocking Reaction force receiving member

Claims (2)

[Claims] 1. A front pipe having an outer diameter smaller than an inner diameter of a buried pipe buried in the ground and divided into a front trunk and a rear trunk, and a front pipe having a front pipe with a front pipe having an inner diameter smaller than an inner diameter of a buried pipe provided at a front end of the front trunk. A small-diameter propulsion device including a cutter head having a small outer diameter, wherein the front body and the rear body are connected by a jack, and the front body is rocked by expansion and contraction of the jack, so that the cutter head allows a buried pipe to be formed. A small-diameter thruster characterized by digging with a digging diameter approximately the same as or slightly larger than the outer diameter. 2. The small-diameter thruster according to claim 1, wherein an outer cylinder having an outer diameter substantially equal to an outer diameter of the buried pipe is provided on an outer periphery of the front pipe.