JPH0433959B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to sewer pipes, gas pipes,
This article relates to a buried pipe boring machine that is a double pipe boring machine used for trenchless burying of cable pipes, etc.

[Prior Art] As shown in Fig. 4, a conventional buried pipe excavator is capable of feeding and retracting an outer pipe drill head 2 and an inner pipe drill head 3 on a bed 1 back and forth using cylinders 1a and 1b, respectively. When the cylinder 1b is operated, the inner pipe drill head 3 slides back and forth with respect to the outer pipe drill head 2, and when the cylinder 1a is operated, the outer pipe drill head 2 and the inner pipe drill head 3 are moved simultaneously. It is designed to slide back and forth.

1c is a guide roller for holding the outer tube 5 on the center line so that it does not swing during drilling, 3a is a chuck for the inner tube, and 2a is the tip of the drill head for the outer tube. In one case, the tip part 2a does not rotate;
In some cases, the outer tube 5 is simply pushed. In the case of rock or gravel, it is necessary to rotate the outer tube 5, so if a chuck is provided on the drill head 2 and the structure is configured to rotate it, the length l of the drill head 2 will become longer, and the length L will also be longer. It had the disadvantage of becoming. However, if the machine length L is long, it is necessary to increase the diameter of the starting pile on which the underground excavator is installed, and in the case of a model in which the outer and inner pipes are rotated for feeding, the starting pile must be increased. An increase in the cost of drilling is inevitable.

Therefore, the outer pipe 5 to be dug and laid with a buried pipe excavator
is about 250mmψ~1000mmψ, and the outer pipe diameter is 400mmψ
If this is the case, even if an attempt is made to cut a joint thread in the joint portion 5c, it will be difficult to cut the thread due to pipe distortion, so welded joints are frequently used, and pipe connections are laborious. Furthermore, regardless of the type of joint, the fewer the number of joints, the better the excavation efficiency will be, and the pipe cost will also be reduced. Therefore, it is possible to use a buried pipe excavator without increasing the length of the machine as much as possible.
There was a desire to develop a buried pipe excavator with long rods (inner and outer pipes).

[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned circumstances, and provides a buried pipe excavation method that allows the use of longer inner and outer pipes than before when the length L is constant. The aim is to provide opportunities for

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention provides a double pipe boring machine having an inner pipe drill head and an outer pipe drill head. It is composed of an upper case that is pivotally supported and holds an outer tube between it and a lower case, and a cylinder that is connected to the upper case and opens and closes the upper case.

Further, the lower case and the upper case have a structure in which a chuck roller that contacts the outer tube is rotatably supported, and a drive device is connected to at least one of the chuck rollers. This is what I did.

[Function] The drill head for the outer tube has an upper case pivotally supported by the lower case in a facing manner to grip the outer tube.A cylinder is connected to the upper case and opens and closes, so the inner and outer tubes are When the upper case 2 is opened with a cylinder, it can be dropped from above in the direction of the arrow as shown in FIG. 3, and the outer tube can be grasped by closing the upper case with the cylinder.
Therefore, since the outer tube can be attached to the outer tube drill head by opening it and dropping it into the head, the length of the outer tube used in the present invention can be reduced to _l2 compared to the conventional outer tube length _l1 . It can be made longer. Although the outer tube drill head 1 in FIG. 3 is shown opening upward and downward, in reality it opens and closes left and right with respect to the axial direction, as will be described later.

When a chuck crawler that contacts the outer tube is rotatably supported on the lower case and upper case,
The outer tube can also be rotated by gripping it. Also, at least one of the chat crawlers
If a drive device is connected to the chuck roller, the gripped outer tube can be rotationally driven by driving the chuck roller with the drive device. Therefore, the outer tube can be rotated and fed.

[Example] An example of the present invention will be described below based on the drawings. In the figure, the same reference numerals are given to the parts corresponding to those in the conventional example, and the explanation of the parts will be omitted.

Fig. 1 is an explanatory diagram of an outer pipe drill head showing an embodiment of the present invention, Fig. 2 is a partial sectional view illustrating a chuck crawler and its driving device, and Fig. 3 is an explanatory diagram of an embodiment of the invention. It is a front view of the underground pipe excavation machine shown. 1A and 1B show a drill head 2 for an outer tube, which is a feature of the present invention, and the drill head 2 slides on a bed 1 by the operation of a cylinder 1a (FIG. 3). 2b is a lower case, on which the lower chuck crawler 2c shown in FIG. It is adapted to be held in contact with the lower chuck roller 2c. 2d is an upper chuck crawler, and FIG. 1A shows a case where the upper chuck crawler 2d is closed, and FIG. As shown in FIGS. 1A and 1B, the upper chuck roller 2d is opened and closed by opening cylinders 2f and 2f attached to the left and right sides of the lower case 2b via the upper cases 2e and 2e. As shown in FIG. 1A, when the upper chuck roller 2d is closed, the outer tube is strongly tightened by the upper and lower four chuck crawlers. The outer diameter surface of the lower chuck roller 2c, as shown in FIG. A protrusion is formed. Figure 1 C to H show various shapes of this protrusion.
c and 2c are installed so that the helical protrusions are symmetrical. D is a linear protrusion parallel to the axis, and E is a linear protrusion parallel to the axis D, and linear grooves parallel to the circumferential direction are further machined to form a lattice-like chevron protrusion. The shape of the protrusion is appropriately selected depending on the material, diameter, load, etc. of the outer tube. FIG. 2 is a diagram illustrating the drive device of the lower chuck roller 2c, in which the roller shaft 2g, to which the lower chuck crawler 2c is fixed with a key, is pivotally supported at both ends by the lower case 2b via bearings 2h, 2h. At the same time, an oil motor 6 is attached to one end. By driving the oil motor 6, the lower chuck roller 2c rotates. Second
Although not shown in the lower chuck roller 2c in the figure, the above-mentioned protrusions are engraved.

Also, the upper chuck crawlers 2d, 2d shown in Fig. 1A and B are the lower chuck crawlers 2d shown in Fig. 2.
It may have the same configuration as c, or it may have a free structure in which the outer circumferential surface of the roller is made into a smooth cylindrical shape and the oil motor 6 is not attached. The structure of the upper chuck crawlers 2d, 2d is selected depending on the rotational force required by the outer tube. If a strong rotational force is required, the structure of the lower chuck crawlers 2c, 2d is selected depending on the rotational force required by the outer tube.
c and the upper chuck crawlers 2d, 2d are drive types, and if there is no need for a very strong rotational force,
It is preferable that only the lower chuck crawlers 2c, 2c are of the drive type.

The buried pipe excavating machine of the present invention has the above-mentioned conventional drill head 2 except for the outer pipe drill head 2 shown in FIGS. 1A and 1B.
The structure is the same as that shown in the drawings, and has already been explained in the conventional example.

To work using the buried pipe excavation machine of the present invention,
The outer pipe drill head 2 and the inner pipe drill head 3 are fed to the position indicated by the chain line at the left end in Fig. 3, and when the drilling for two pipes is completed, the open cylinders 2f, 2f are shortened as shown in Fig. 1, and the upper Open the chuck rollers 2d, 2d, release the grip on the outer tube 5, and remove the outer tube drill head 2 and the inner tube drill head 3.
Move it to the position indicated by the solid line on the right end, and drop the set inner and outer tubes 4 and 5 from above in the direction of the arrow.

Next, as shown in FIG. 1A, the open cylinder 2
Extend f and 2f and install the upper chuck crawler 2.
d, 2d are closed, and the open cylinders 2f, 2 are closed.
When hydraulic pressure is applied to f, the lower chuck crawler 2
c, 2c and the upper chuck rollers 2d, 2d, the protruding tip on the outer periphery of the driven roller is the outer pipe 5.
The drill head for outer tube 2 strongly presses against the smooth outer circumferential surface of the drill head and bites into the surface, so it grips the outer tube securely.
It becomes possible to transmit force from the outer tube 5 to the outer tube 5. Next, with this outer pipe drill head 2 gripping the outer pipe, the cylinder 1b is hydraulically actuated, and the inner pipe drill head 3 is moved to the left from the position shown in the third figure to connect the socket joints 4a and 4b. . In this case, the chuck 3a is closed and grips the inner tube 4. Next, actuate the cylinder 1a to move the outer pipe drill head 2 to the left (in this case, the inner pipe drill head also moves), with the tip of the outer pipe 5a and the rear end of the outer pipe 5b in contact with each other. The abutted joint portions 5c are welded and connected. This joint portion 5c may be a threaded joint instead of a welded joint, but in that case, a clamp for gripping the outer tube 5b is required near the guide roller 1c and on the drill head side. Furthermore, as the diameter of the outer tube increases, it becomes more expensive to thread the joint, so welded joints are often used. Next, drill head 2 for the outer pipe
When the oil motor of the drill head 3 for the inner tube is driven to rotate the outer tube 5 and the inner tube 4 and the cylinder 1a is operated at the same time, the drill head 2 for the outer tube and the drill head 3 for the inner tube move forward to the left, and the outer tube 5 is rotated. and inner tube 4 at the same time. The rod tip 1d of the cylinder 1b of the inner pipe drill head 3 is connected to the outer pipe drill head 2, and is configured to move back and forth with the outer pipe drill head 2. When the drill head 2 is fed to the position indicated by the chain line by the rotation and feeding of the inner and outer tubes, the grip on the outer tube 5 is released again as described above and the same operation is repeated.
This involves continuous excavation.

The illustrated embodiment is a case in which the outer pipe is fed while being rotated, but there is also a type of buried pipe excavator that only feeds the outer pipe without rotating it. In the case of this type, the chuck rollers 2c and 2d are not necessary, and the structure may be such that the gripping is performed simply by the lower case 2b and the upper case 2e. In this case, the recess 2j of the lower case 2b and the upper case 2
It is also possible to fix an abutting member on the abutting surface of e to the outer tube 5 so as not to damage the outer tube 5 when gripping.

Comparing the buried pipe digging machine of the present invention (shown in the third figure) with the conventional buried pipe digging machine (shown in the fourth figure) having a chuck that grips and rotates the outer pipe, it is found that, for example, when the machine length L is the same, the former can be used. The rod length l ₂ can use rods (inner and outer tubes 4 and 5) that are nearly twice the latter rod length l ₁ .

[Effects of the Invention] As explained in detail above, the buried pipe excavation machine of the present invention has a long usable rod length (inner and outer pipes), reduces the number of rod connections, and extends the distance that can be excavated with one rod. The rod length is increased, dramatically improving excavation efficiency, and the number of joints is reduced, reducing the cost required for the rod.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of a drill head for an outer pipe showing an embodiment of the present invention, in which A shows the case when the upper chuck roller is closed, B shows when the upper chuck crawler opens, and H to H show the drill head for an outer pipe. Fig. 2 is a partial cross-sectional view illustrating the chuck crawler and its driving device, and Fig. 3 is a front view of a buried pipe excavation machine showing an embodiment of the present invention. , FIG. 4 is a front view of a conventional buried pipe excavator. 1...Bed, 1a, 1b...Cylinder, 1
c...Guide roller, 1d...Rod tip, 2
...Drill head for outer pipe, 2a... Tip part, 2b
...Lower case, 2c...Lower chuck roller, 2d...Upper chuck crawler, 2e...Upper case, 2f...Opening cylinder, 2g...
...Roller shaft, 2h...Bearing, 2j
...Recessed portion, 3...Drill head for inner pipe, 3a...
Chuck, 4...Inner pipe, 5, 5a, 5b...Outer pipe, 5c...Joint part, 6...Oil motor.

Claims (1)

[Scope of Claims] 1. A drill head for an outer pipe in a double pipe boring machine having a drill head for an inner pipe and a drill head for an outer pipe is gripped between a lower case and a lower case that is pivotally supported to face the lower case. A buried pipe excavator comprising an upper case and a cylinder connected to the upper case to open and close the upper case. 2. The buried pipe excavator according to claim 1, wherein a chuck crawler that contacts the outer pipe is rotatably supported by the lower case and the upper case. 3. The buried pipe excavator according to claim 2, wherein a drive device is connected to at least one of the chuck crawlers.