JPH0547833Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Field of Application) The present invention relates to underground excavators, and particularly relates to a cutter head support structure of a small diameter tube propulsion machine.

(Conventional technology) Copper pipes, etc. have been buried underground for water supply, sewerage, telephone cables, and other purposes, but this burying machine has a method of burying pipes while digging a horizontal hole. Underground excavators are being used.

However, there are many types of underground excavators depending on the purpose, but the one that can minimize construction pollution such as traffic interruption, vibration, and ground subsidence is a small-diameter pipe excavator that can bury pipes in only a small vertical shaft. Widely used.

For example, as shown in Fig. 2, this small-diameter pipe boring machine has a casing b inside a leading pipe a, a cutter head c at the tip of the casing b, and a screw conveyor d connected to the rear of the head c. Then, the cutter head c is rotated by a drive device (not shown) at the rear, and the direction correction cylinder e provided near the inner circumference of the leading pipe a moves the leading pipe a forward while correcting its excavation direction, and the buried pipe f is inserted from behind. It has a structure that will be buried.

(Problem that the invention attempts to solve) However, in the above structure, the diameter is 120φ.
However, with the increase in buried pipes in recent years, the types of buried pipes with this diameter are limited, so it is desired to install buried pipes with larger diameters. Ta. In order to meet these demands, a model with the same structure but three times as large in diameter has begun to be used. However, when the propulsion force is increased, the conventional structure in which the cutter head is supported by a screw conveyor inside the casing becomes difficult to carry during excavation. This caused the head to wobble, and although this could be used when excavating earth and sand, it became impossible to excavate when excavating gravel.

In view of this, the present invention was devised for the purpose of providing a cutter head structure for a small-diameter pipe excavator that can be used without any problem in gravel excavation without significantly changing the conventional structure.

(Means for solving the problem) A non-rotating casing part consisting of an outer cylinder having approximately the same diameter as the installed pipe and an inner cylinder arranged concentrically with the outer cylinder, and a disk cutter pivotally supported on the front surface. a rotating cutter head consisting of a cutter head and a drum fixed to the rear of the cutter head, and a non-rotating rocker rotatably supported by the front part of the casing part and rotatably supporting the cutter head. and a screw conveyor fixed to the central portion of the cutter head portion and extending rearward through the swinging portion and the central portion of the casing portion, the thrust acting on the cutter head portion and the radial a bearing that supports a load; a rocking body inscribed in the spherical surface of a spherical body fixed to the front part of the inner cylinder of the casing part; and a hollow member fixed to the front part of the rocking body and supporting the bearing on its outer periphery. a direction correction cylinder pivotally supported by the rear part of the rocking body and the casing part, and a front and rear screw conveyor connected to be swingable at the center of curvature of the spherical body. The invention is characterized in that it is comprised of the above-mentioned screw conveyor.

(Function) With this configuration, the cutter head is rotatably supported via a bearing on the swinging part which is swingably supported on the casing part, thereby reliably absorbing the radial load acting on the cutter head. At the same time, the thrust load acting on the cutter head is supported by the casing via the bearing, the swinging section consisting of a hollow member and a swinging body, and the direction correction cylinder, so that the thrust load acting on the cutter head is The direction correction cylinder pivotally supported by the casing part and the swinging part does not act on the screw conveyor, and the direction of the cutter head part can be reliably corrected via the bearing.

(Example) The present invention will be described below with reference to an example shown in FIG.

The cutter head support structure for a small-diameter pipe excavator according to the present invention has a cutter head 1 equipped with a disk cutter 2 on the front and a drum 3 on the rear, with a
A screw conveyor 4 extending backward is fixedly installed,
This screw conveyor 4 is inserted into a casing 5 provided at the rear of the head 1, and the screw conveyor 4 is installed in a small-diameter pipe excavator in which the base 7 of a flap-like earth and sand inlet 6 is placed close to the gauging 5. The front part 4a and the rear part 4b are divided into a front part 4a and a rear part 4b, which are connected so as to be swingable, and a hollow member 8 having the same inner diameter as the casing 5 is provided between the casing 5 and the base part 7 of the earth and sand inlet 6. A bearing 9 capable of supporting thrust and radial loads is provided between the member 8 and the drum 3.

This bearing 9 is designed to receive both thrust load and radial load in order to ensure support of the cutter head 1, and has a fixed side 9a fitted externally to the hollow member 8 and a rotating side 9a fitted internally to the drum 3. The fixed side 9a is connected to the side 9b via a ball 9c, and the fixed side 9a is connected to the hollow member 8 and a bearing holder 11 provided at the base 7 of the earth and sand inlet 6 via a fastening means 12 such as a bolt. It is fixed and movement in the front and back direction is restricted. and the bearing presser 11
A seal member 13 is provided on the circumferential surface between the drum 3 and the drum 3.

Further, the rotating side 9b is positioned between a bearing holder 14 fitted from the rear end of the drum 3 by fastening means 15 such as a bolt. A spherical body 19 having a convex spherical surface is fixed to the outer periphery of the front end of the casing 5, and the inner surface of one side 8a of the hollow member 8 is held in sliding contact with the convex spherical surface of the spherical body 19. It's becoming like that.

Furthermore, a rocking body 20 is provided between the annular member 18 and the casing 5 and is circumscribed to the sliding surface 18a and inscribed to the spherical body 19. Therefore, the oscillating body 20 is fitted between the annular member 18 and the spherical body 19 of the casing 5 on the inside of the guide pipe 17, so that the inside of the guide pipe 17 is kept sealed from the outside.

Further, the rocking body 20 has a bolt 21 of the piston rod of the direction correction cylinder 10 at the rear end.
etc., and the hollow member 8 is pivoted at the front end.
It is fixed to the rear end of the body with a bolt 22 or the like.

Then, the outer surface of this hollow member 8 and the drum 3
A sealing member 23 is provided between the inner surface and the outer surface to seal the outer surface.

The screw conveyor 4 is divided into a front part 4a and a rear part 4b at the center of curvature of the spherical body 19, and each end of the screw conveyor 4 is divided into a front part 4a and a rear part 4b. It is formed into a universal joint and is swingably connected by a pin 16.

At the rear of the cutter head 1 is a leading pipe 17 on the outer periphery.
It has the casing 5 and a screw conveyor at the rear part 4b that is inserted into the casing 5. On the outer periphery of the casing 5, there is a plurality of direction correction cylinders 1 for correcting the excavation direction.
0 is swingably provided in the middle part.

Therefore, when the cutter head 1 swings around the pin 16 between the screw conveyors 4a and 4b, the swinging body 20 swings around the annular member 1.
8 and the spherical body 19, and the direction correction cylinder 10 corrects the direction accordingly.

Next, to operate this cutter head 1, thrust applied by a rear driving device (not shown) is transmitted to the cutter head 1 through the leading pipe 17, and rotational force is transmitted to the cutter head 1 through the screw conveyors 4a and 4b. The cutter head 1 rotates together with the drum 3 and the front and rear screw conveyors 4a and 4b, and is supported by a bearing 9 and a hollow member 8 and swings vertically and horizontally around a pin 16 within a certain angle range. be able to.

In this embodiment, the bearing uses balls, but a bush type bearing may also be used.

(Effects of the invention) Since the invention is configured as explained above, the cutter head during excavation is reliably supported by the bearing, the swinging member consisting of the hollow member and the swinging body, and the direction correction cylinder, which promotes the excavation. It does not wobble due to reaction force and can withstand large loads, making it possible to crush large-diameter gravel.

Furthermore, by preventing wobbling during excavation and propulsion, propulsion accuracy can be dramatically improved.

Further, in the present invention, it is possible to correct the direction of the cutter head itself, which is a rotating body, by expanding and contracting the direction correction cylinder, and the direction correction effect appears immediately, improving construction accuracy.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a cutter support structure for a small diameter tube propulsion device according to the present invention, and FIG. 2 is a side sectional view of a cutter support structure for a conventional small diameter tube propulsion device. 1...Katsuta head, 2...Disk cutlet,
3...Drum, 4...Screw conveyor, 4a
...Front screw conveyor, 4b... Rear screw conveyor, 5... Casing, 6... Sediment inlet, 7... Base, 8... Hollow member, 8a...
On one side, 10... direction correction cylinder, 16... pin.

Claims (1)

[Scope of utility model registration request] A non-rotating casing part consisting of an outer cylinder with approximately the same diameter as the installed pipe and an inner cylinder arranged concentrically with the outer cylinder, a cutter head with a disk cutter pivoted on the front, and a cutter head fixed to the rear of the cutter head. a rotating cutter head consisting of a drum, a non-rotating swinging part which is pivotably supported on the front part of the casing part and rotatably supports the cutter head, and a central part of the cutter head. In a small-diameter tube propulsion machine that is fixed and includes the swinging part and a screw conveyor extending rearward through a central portion of the casing part, a cutter head part is rotatably supported with respect to the swinging part, and
a bearing that supports the thrust and radial load acting on the cutter head; a rocking body inscribed in the spherical part of a spherical body fixed to the front part of the inner cylinder of the casing; and a rocking body fixed to the front part of the rocking body; The swinging section includes a hollow member that supports a bearing on its outer periphery, a direction correction cylinder pivotally supported by the rear part of the swinging body and the casing section, and the swinging section is swingably connected at the center of curvature of the spherical body. 1. A cutter head support structure for a small-diameter tube propulsion machine, characterized in that it is comprised of a front and a rear screw conveyor.