JPH0452835B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a pipe burying device, and particularly to a pipe burying device suitable for burying small diameter pipes.

[Background of the invention]

An apparatus for burying small-diameter pipes, for example, pipes with a diameter of 800 mm or less, is described in Japanese Patent Application Laid-Open No. 57-29797. Next, this pipe embedding device will be explained with reference to FIG. In the figure, this pipe burying device includes a hydraulic cylinder 3 as a propulsion means in a starting shaft 2, and a rotary excavator drive and viscosity imparting liquid supply section 4.
and set up. On the other hand, a rotary excavator 6 is rotatably supported at the front part of the excavator main body 5.
are provided with digging blades 7, 8, stirring blades 9, 10, and an inlet 11 for the viscosity imparting liquid. The front part of a buried pipe 12 having an outer diameter smaller than the outer diameter of the rotary excavator 6 is connected to the rear part of the excavator main body 5, and the rear part of the buried pipe 12 is brought into contact with the hydraulic cylinder 3. The excavating tool rotating shaft and viscosity imparting liquid supply pipe 13 is passed through this buried pipe 12.
Both ends of the rotary excavator 6 are connected to the rotary excavator 6 and the rotary excavator drive unit/viscosity imparting liquid supply unit 4, respectively. A pressure holding frame 15 for holding earth and sand pressure is provided in the annular gap 14 formed between the excavated hole on the side of the starting shaft 2 and the buried pipe 12, and an earth discharge port 16 is provided in the pressure holding frame 15.

Next, the operation of the pipe embedding device constructed as described above will be explained. First, the rotary excavator drive unit and viscosity imparting liquid supply unit 4 is driven to rotate the rotary excavator 6, and the excavator blades 7, 8 of the rotary excavator 6 are rotated.
While excavating the ground 1 with the rotary excavator 6, a viscosity imparting liquid is injected from the injection port 11 of the rotary excavator 6, and the injected viscosity imparting liquid and the excavated soil are transferred to the rotary excavator 6.
A viscous liquid mixed earth and sand 17 is produced by stirring and mixing using stirring blades 9 and 10 . At this time, since the outer diameter of the rotary excavator 6 is larger than the outer diameter of the buried pipe 12,
An annular gap 14 is formed between the excavated hole and the buried pipe 12. For this purpose, the viscous liquid mixed earth and sand 17 generated in the vicinity of the rotary excavator 6 is forced backward by the pressure of the viscosity imparting liquid injected from the injection port 11 and the propulsive force of the hydraulic cylinder 3. The soil is discharged from the discharge port 16 of the pressure holding frame 15 to the starting shaft 2 through the outer circumference of the main body 5 and the annular gap 14 . On the other hand, simultaneously with the above-mentioned excavation of the earth 1, the hydraulic cylinder 3 is extended to propel the buried pipe 12. When the hydraulic cylinder 3 reaches the stroke end, the hydraulic cylinder 3 is retracted and the starting shaft 2
By connecting a new buried pipe 12 inside and repeating the above-described operation, the buried pipes 12 can be successively buried.

In this way, the above-mentioned pipe burying device excavates the ground 1 in the front part of the excavator main body 5 and turns it into viscous liquid mixed earth and sand, so the insertion resistance is reduced and the connection between the excavation hole and the buried pipe 4 is reduced. Since the annular gap 14 between them is filled with earth and sand mixed with viscous liquid, the frictional resistance between the earth 1 and the buried pipe 12 is reduced. Therefore, compared to the conventional consolidation method, the driving force applied to the buried pipe 12 can be reduced, and since the force acting on the buried pipe 12 is small, damage to the buried pipe 12 is extremely reduced, and moreover, the direction This has effects such as improved accuracy.

However, the above-mentioned pipe burying device uses a rotary excavator 6.
The structure is such that the rotation is performed via the rotating shaft 13 from the rotary excavator drive unit and viscosity imparting liquid supply unit 4 installed in the starting shaft 2, so that as the propulsion distance (tube buried length) increases, If the rotating shaft 13 is twisted or the buried pipe 12 is buried in a meandering manner, there are problems such as difficulty in connecting the rotating shaft 13.

As a countermeasure to this problem, a method can be considered in which a hydraulic motor or electric motor (with a speed reducer) as a drive device for the rotary excavator 6 is installed inside the excavator main body 5, and the rotary excavator 6 is rotated by this. When applied to a small diameter excavator, it is necessary to arrange the hydraulic motor or electric motor so that the drive shaft of the hydraulic motor or electric motor and the center of rotation of the rotary excavator 6 are concentric with each other in terms of space. However, in reality, there are few cases in which the drive shaft of a hydraulic motor or electric motor is the center, so the passage for supplying the viscosity imparting liquid to the injection port 11 provided at the center of the rotary excavator 6 is It has to be secured in a part other than the drive shaft, that is, in the outside part of the hydraulic motor or electric motor, which makes the structure extremely complicated, and there is a problem that it cannot be applied to an extremely small excavator with an outer diameter of about 200 mφ.

[Purpose of the invention]

An object of the present invention is to prevent twisting of the rotating shaft by installing the driving device of the rotating excavating tool inside the excavating machine main body.
It solves problems such as connection failure, reduces the radial direction of the drive device and can be applied to extremely small diameters, and has a simple structure with a supply passage for the viscosity imparting liquid inside the drive device. Our objective is to provide burial equipment.

[Summary of the invention]

In order to achieve this object, the present invention has a rotary excavator mounted on the front part of the excavation machine main body, an injection port for injecting a viscosity imparting liquid into the excavated earth and sand, and a Connecting the front part of a buried pipe whose outer diameter is smaller than the outer diameter of the rotary excavation tool to the rear part, and bringing the rear part of the buried pipe into contact with a propulsion means installed in the starting shaft to rotate the rotary excavation tool. At the same time, the viscosity-imparting liquid is injected into the excavated soil from the injection port to form a viscous liquid mixed earth and sand, and the viscous liquid mixed earth and sand is transported backward through the outer periphery of the excavation machine body and propelled. In pipe burying equipment,
The driving device of the rotary excavation tool is composed of a hollow hydraulic jack and a screw shaft that is inserted through the hollow part of the hollow hydraulic jack and rotates by the expansion and contraction movement of the hydraulic jack. installed inside the excavator main body so that expansion and contraction are performed along the axial direction of the excavator main body, and the tip of the screw shaft is connected to a rotating excavator,
By providing a passage inside the screw shaft for supplying the viscosity imparting liquid to the injection port, the rotary excavator can be driven from the excavator main body, and the drive device can be made smaller in the radial direction, making it extremely compact. It can also be applied to large diameter ones.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is a longitudinal sectional view of a pipe burying device according to the present invention, and FIG. 2 is a diagram showing its operation. In the figure, the same reference numerals as in Figure 3 are the same.
or something equivalent. In this pipe burying device, the driving device for the rotary excavation tool 6 is composed of a hollow hydraulic jack 18 and a screw shaft 19 that is inserted through the hollow part of the hollow hydraulic jack 18 and rotates by the expansion and contraction movement of the hydraulic jack 18. are doing. The jack body 18a of the hollow hydraulic jack 18 is mounted on the inner wall of the excavator body 5 so that its rod 18b can expand and contract along the axial direction of the excavator body 5. A screw nut 20 is fixed to the tip of the rod 18b. The screw shaft 19 has a thread 19a cut from its middle portion to its rear end, and the screw shaft 19 is threaded into the screw nut 20.
The screw shaft 19 is arranged on the rotational center line of the rotary excavator 6, and the tip of the screw shaft 19 is connected to the back surface of the rotary excavator 6, and the rear end is attached to a bearing 21 provided on the excavator main body 5. is supported by Further, a passage 22 for supplying the viscosity imparting liquid to the injection port 11 is provided inside the screw shaft 19 . The passage 22 is connected to the screw shaft 19
The rear end portion is connected via a swivel joint 23 to a conduit 24 that leads the viscosity imparting liquid from a viscosity imparting liquid supply section (not shown) in the starting shaft.
In addition, 18c and 18d are hollow hydraulic jacks 18.
25 is a sealing material that seals between the excavator main body 5 and the rotary excavator 6, and 26 is a seal between the rotary excavator 6 and the hollow hydraulic jack 1.
This is a sealing material that seals between the jack body 18a of No. 8 and the jack main body 18a.

Next, the operation of this embodiment will be explained.

As shown in FIG. 1, when the rod 18b of the hollow hydraulic jack 18 is in the most contracted state, when hydraulic pressure is supplied from a hydraulic source (not shown) to the extension side port 18d, the hydraulic pressure increases as shown in FIG. The rod 18b of the jack 18 is extended. When the screw nut 20 moves due to the extension of the rod 18b,
A screw shaft 19 screwed into this rotates. Rotational torque (kgf-) generated on the screw shaft 19 by the rod thrust of the hollow hydraulic jack 18
cm) is expressed by the following formula.

T=Fa・l/2π・η Where, Fa: Axial load (kgf) l: Screw shaft lead (cm) η: Screw efficiency The rotation of the screw shaft 19 directly becomes the rotation of the rotary drilling tool 6. The rotary excavator 6 continues to rotate in the same direction until the extension of the rod 18b of the hollow hydraulic jack 18 reaches the stroke end. Then, when the rod 18b extends to the stroke end, a directional control valve (not shown) is switched to supply pressure oil to the contraction side port 1 of the hollow hydraulic jack 18.
8, the rod 18b contracts, the screw shaft 19 rotates in the opposite direction to that when it is extended, and the rotary excavator 6 also rotates in the opposite direction. In this way, by repeating the expansion and contraction operations of the hollow hydraulic jack 18, the rotary excavator 6 excavates the ground 1 while rotating forward and backward. Further, in the above operation, the viscosity imparting liquid is supplied to the injection port 11 through the passage 22 in the screw shaft 19.

Therefore, in this embodiment, since the drive device for the rotary excavator 6 is installed inside the excavator main body 5, the third
The problems of the pipe burying device shown in the figure, such as the twisting of the rotating shaft and the inability to connect the rotating shaft, can be solved. In addition, since the drive device is composed of the hollow hydraulic jack 18 and the screw shaft 19, the outer diameter of the drive device itself can be reduced to the outer diameter of the hollow hydraulic jack 18, and the outer diameter of the excavator can be as small as about 200 mφ. It can also be applied to caliber ones. Furthermore, since the supply passage for the viscosity imparting liquid is provided within the screw shaft 19, the structure is also simple.

〔Effect of the invention〕

As explained above, according to the present invention, since the driving device of the rotary excavator is installed inside the excavator main body, the conventional problems such as twisting of the rotary shaft and inability to connect can be solved. Furthermore, since the drive device is composed of a hollow hydraulic jack and a screw shaft, the outer diameter of the drive device itself can be reduced to the outer diameter of the hollow hydraulic jack, and it can be applied to a device with an extremely small diameter. Furthermore, since the supply passage for the viscosity imparting liquid is provided within the screw shaft, the structure can be simplified.

[Brief explanation of drawings]

1 and 2 show one embodiment of the present invention, FIG. 1 is a longitudinal cross-sectional view of a pipe burying device according to the present invention, and FIG.
The figure shows its operation diagram, and FIG. 3 is a longitudinal cross-sectional view showing a conventional pipe burying device. 2...Starting shaft, 3...Hydraulic cylinder, 5...
Excavator body, 6...Rotary excavation tool, 11...Inlet, 14...Buried pipe, 18...Hollow hydraulic jack, 18a...Jack body, 18b...Rod, 19...Screw shaft, 20... Screw nut, 22... Passage for supplying viscosity imparting liquid.

Claims (1)

[Claims] 1 A rotary excavator is attached to the front part of the excavator body, an injection port for injecting a viscosity imparting liquid into excavated soil is provided on the rotary excavator, and the outer diameter of the rotary excavator is set at the rear of the excavator body. The front part of the buried pipe smaller than the diameter is connected, the rear part of the buried pipe is brought into contact with the propulsion means installed in the starting shaft, and the rotary excavation tool is rotated to excavate the ground, and at the same time A pipe burying device that injects a viscosity imparting liquid into excavated soil from an inlet to form a viscous liquid mixed earth and sand, and propels the viscous liquid mixed earth and sand while transferring it backward through the outer periphery of the excavation machine body. The drive device is composed of a hollow hydraulic jack and a screw shaft that is inserted through the hollow part of the hollow hydraulic jack and rotates by the expansion and contraction movement of the hydraulic jack. The screw shaft is installed inside the excavator main body so as to be carried out along the axial direction of the screw shaft, and the tip of the screw shaft is connected to a rotary excavator, and the viscosity imparting liquid is supplied to the injection port inside the screw shaft. A pipe burying device characterized by providing a passage.