JPH108867A - Rotary drilling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently excavate even a soft rock-bed. SOLUTION: Four drilling means 35 are rotatably fitted to a ringlike drilling edge 2 rotated at a front end part of a head excavating pipe. The drilling means 35 is provided with an rotational axis R with the tip side inclined onto the excavating direction side as well as on the inner diameter side of the ring- like drilling edge 2, and a plural rows of drilling tips are fitted to the outer peripheral surface, along the direction of the rotational axis R.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary drilling machine for drilling a ground by rotating a ring-shaped drilling blade.

[0002]

2. Description of the Related Art There is a propulsion burial method as a construction method for burying a vinyl chloride pipe, a steel pipe or the like in the ground. In this method, the top excavation pipe is inserted almost horizontally into the soil from the side wall of the shaft, and excavation is performed. This is to bury the pipe without digging.

[0003] As a general excavation method in this propulsion burial method, a ring-shaped excavator having a plurality of excavating tips in the circumferential direction is arranged in front of a leading excavation pipe, and the ground is rotated by rotating the ring-shaped excavator. Although a structure for excavation is conceivable, this has a drawback that the excavation chips are not bite particularly when excavating the rock, and the chips are idle on the rock, so that efficient excavation cannot be performed. Therefore, in a stratum including such a bedrock, a hammer-type drilling pipe which attaches an air hammer to a leading drilling pipe and crushes the bedrock with the impact force of the hammer to move forward while being rocked is widely used.

[0004]

However, in the above-mentioned hammer type excavation pipe, there is no problem when excavating relatively hard rock in rock, but when excavating soft rock such as sandstone. However, since the compaction action of compacting the crushed pieces rather than the crushing action of the hammer becomes stronger, it becomes difficult to efficiently drill the excavation pipe.

Accordingly, an object of the present invention is to provide a rotary drilling machine capable of efficiently excavating even soft rock.

[0006]

In order to achieve the above object,
According to the present invention, when a ring-shaped excavation blade is rotated to excavate underground, the ring-shaped excavation blade is inclined toward the excavation direction side end, the tip side is inclined toward the inner diameter side of the ring-shaped excavation blade and toward the excavation direction side. An excavating means having a rotating shaft and a drilling tool provided around the rotating shaft was rotatably mounted. The “digging tool” refers to a tool for digging the ground by relative motion with the ground, and includes not only a tip-shaped tool but also a tool having a continuous blade surface such as a straight blade.

[0007] It is desirable to dispose an inner diameter side excavating blade that rotates in a direction opposite to the rotation direction of the ring type excavating blade on the inner side of the ring type excavating blade.

The narrow angle α between the extension of the rotation axis of the digging means and the center axis of the ring-shaped digging blade is preferably 55 °.

[0009] The excavating means is provided with a body in the form of a rotating body about a rotation axis, and a plurality of excavating tips protruding from the outer peripheral surface of the body. Specifically, the base is formed into a disk shape, or the base is formed to have a diameter reduced toward the tip of the rotation shaft, and the excavation chips are arranged at a plurality of positions in the axial direction of the rotation shaft.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIG. However, in the following description,
An example is shown in which the present invention is applied to a pipe burial apparatus used in a propulsion burial method, which is a type of excavation apparatus.

As shown in FIG. 1, this pipe burying device connects a ring-shaped digging blade (2) and an inner peripheral digging blade (3) provided at the tip of a leading drilling pipe (1) (tube body) to each other. Reverse rotation,
While excavating the ground, the leading excavation pipe (1) is pushed forward in the horizontal direction with a hydraulic jack or the like, and a pilot pipe (not shown) connected to its rear end is drawn into the drilled hole in order to bury the pipe. It is what you do.

The leading excavation pipe (1) is formed in a cylindrical shape with a steel pipe or the like. This leading excavation pipe (1) rotatably connects the rotary pipe (6) to the excavation direction side (left side in the drawing) of the fixed pipe (5), and is connected to the excavation direction side of the rotary pipe (6). A drilling head (7) comprising a ring-shaped drilling blade (2) and an inner peripheral side drilling blade (3) is connected, and these fixed pipe (5), rotating pipe (6), and ring-shaped drilling blade (2) are connected. ) And the inner peripheral side excavating blade (3) are coaxially arranged about the central axis (OO).

A rotary drive source (10) composed of a hydraulic motor or the like is eccentrically arranged inside the fixed tube (5). A power shaft (11) of the rotary drive source (10) is connected to a mounting shaft (14) of the inner peripheral cutting edge (3) via a pinion (12) and a first intermediate gear (13). On both sides of the first intermediate gear (13), a second intermediate gear (not shown) that meshes with the first intermediate gear (13) is disposed, and the second intermediate gear is provided on the entire inner peripheral surface of the rotary pipe (6). It is in mesh with the internal gear (15) provided. With the above configuration, when the rotary drive source (10) is activated, the ring-shaped digging blade (2) and the inner circumferential digging blade (3) provided at the distal end of the rotary pipe (6) are driven to rotate in opposite directions. Is done.

The ring-shaped digging blade (2) is a rotating pipe (6).
The pedestal (20), which rotates together with the cylindrical base
A plurality of drilling tips (21) are shrink-fitted over the entire circumference of the tip end surface of the, and are exchangeably mounted by means such as brazing or welding. The inner peripheral side excavating blade (3) has a plurality of excavating tips (31) similarly exchangeably mounted on the surface of a main body (30) having a substantially convex spherical surface. It is arranged on the inner diameter side so as to retreat by a predetermined distance from the tip of the excavating blade (2). The above-mentioned convex spherical surface does not mean only a complete spherical curved surface, but also includes a surface approximated by combining a plurality of planes as shown in the figure. The reason why the shape of the inner peripheral side excavation blade (3) is a convex spherical surface is to enable excavation even on the ground containing a large amount of gravel and cobble stones. Any shape that matches the geology can be selected.

As described above, since the ring-shaped excavation blade (2) and the inner peripheral side excavation blade (3) are rotated in the reverse direction, excavation of rock or the like sandwiched between the two blades (2) and (3) is performed. The object is subjected to a shearing force, and the object to be excavated is finely crushed by the shearing force, so that there is no possibility that the crushed pieces are clogged during the transportation in the earth removal device (16). In order to make this shearing effect more effective, the inner surface of the pedestal (20) of the ring-shaped digging blade (2)
A plurality of excavation tips may be attached so as to face the excavation tips (31) of the inner peripheral side excavation blade (3) (not shown).

As shown in FIGS. 1 and 2, four excavation points are provided on the inner surface of the end (front end) of the ring-shaped excavation blade (2) in the direction of excavation, and at circumferentially equally spaced positions. Means (35) are arranged. As the excavating means (35), various types having an excavating function can be used. In the present embodiment, a case where a so-called three-cone bit is generally used is exemplified.

As shown in FIG. 3, the excavating means (35) fits a base (36) formed in a rotating body shape to a support shaft (39) protruding from a tip end of a mounting member (37). It is composed by combining them. A plurality of balls (40) are rotatably interposed between the base (36) and the support shaft (39), whereby the base (36) can rotate about the rotation axis (R). Supported by The base body (36) is formed in a substantially conical shape in which the tip end side of the rotation shaft (R) is reduced in diameter, and its outer peripheral surface has a plurality of rows (three rows in the drawing) of excavation tips (38). ) Is detachably attached. Although not shown, the mounting member (37) has a built-in lubrication mechanism and the like for lubricating the rolling surface of the ball (40).

The base (36) is supported by the support shaft (39) in an inwardly inclined posture such that the tip end side of the rotation shaft (R) is inclined toward the inner diameter side of the leading excavation pipe (1) and toward the excavation direction. At this time, the excavating means (35) is arranged at a position where a part of the base body (36) protrudes further in the excavation direction than the foremost part of the ring-shaped excavating blade (2). Thereby, preliminary excavation by the excavation means (35) can be performed simultaneously with or prior to excavation by the ring-shaped excavation blade (2), and the biting property of the ring-shaped excavation blade (2) can be improved. .

The inclination angle α of the excavating means (35), that is, the narrow angle α between the extension of the rotation axis (R) of the excavating means (35) and the central axis (OO) of the leading excavating pipe (1) is If it is too small, the excavating means (35) does not rotate during excavation, and if it is too large, sufficient excavating power cannot be exerted.
Since the most preferable inclination angle α varies depending on the geology, the diameter of the buried pipe, and the like, it cannot be said unconditionally, but is preferably about 55 °.

The excavating means (35) is formed by forming an axial cutout at a predetermined position of the pedestal (20) of the ring-shaped excavating blade (2), and fitting and fixing a mounting member (37) to the cutout. , Integrated with the pedestal (20).

In this configuration, the ring-shaped digging blade (2)
Is rotated about a central axis (OO), the excavating means (35) rotates (revolves) integrally with the ring-shaped excavating blade (2), and at this time, the frictional force received from the ground causes
The excavating means (35) rotates around the rotation axis (R).
Accordingly, even if the ring-shaped excavating blade (2) tries to run idle without cutting into the rock, the excavating tip (38) of the excavating means (35) that rotates and revolves around the front peripheral portion of the ring-shaped excavating blade (2). In particular, the ground on the inner diameter side is excavated in a ring shape over a wide range, so that the ring-shaped excavation blade (2) can recover the biting property of the opposing ground. Therefore, even if the target ground is rock, excavation can be performed smoothly and reliably. When the leading excavation pipe (1) is pushed in by a main pushing device (described later), a part of the pushing force is extended through the excavating means (35) in the direction of the inner diameter side extension of the rotation shaft (R) (the leading excavation pipe). Acts on the center side) and moves the opposing ground to the center axis (O-
Compress in the O) direction. Since the opposing ground is easily collapsed by the compression load, the excavation by the ring-shaped excavation blade (2) is performed more efficiently.

As described above, the apparatus of the present invention can excavate even a bedrock and does not have a structure in which crushed pieces are compacted as in a conventional hammer type, so that even a soft bedrock can be smoothly excavated. Excavation becomes possible. Therefore, it becomes possible to excavate in various hard geological layers (gravel layer, boulder layer, soft / hard rock layer, etc.) with one device, and it is possible to greatly reduce the construction cost.

As the excavating means (35), an excavating tool (38) is provided on the outer peripheral surface, and the tip side of the rotation shaft (R) is inclined in the excavation direction side and the inner diameter side of the leading excavation pipe (1). If so, another structure may be used. For example, the base body (36) may be formed in a disk shape and excavation chips may be attached to the outer peripheral surface in a line. As described above, it is more preferable to provide a plurality of rows of excavation tips (38) in the direction of the rotation axis (R) because the excavation area of the excavation means (35) is increased. The base (36) may have any shape as long as the diameter decreases toward the tip end of the rotation shaft, and various shapes such as a conical shape and a semicircular shape are applicable. Also, the number of excavating means is not limited to four, and an arbitrary number can be selected according to various conditions such as geology, borehole diameter, excavation distance, and the like.

Hereinafter, the procedure of propulsion embedding by this device will be described.

First, a starting shaft and a reaching shaft are excavated at both ends of the pipe burying section, and a main pushing device such as a hydraulic jack, a control panel, a pump for supplying high-pressure water, an imaging means, and the like are provided in or near the starting shaft. Install. Next, the head excavation pipe (1) is sequentially pushed and propelled in the horizontal direction by a hydraulic jack or the like, and the pump is started at the same time. The high-pressure water pumped from the pump is jetted to the opposite ground through a water supply pipe (not shown) provided in the head excavation pipe (1). In this way, the rotary drive source (10) in the head drilling pipe (1) is activated while squirting high-pressure water into the drilling part,
The excavation is started by rotating the ring-shaped excavation blade (2) and the inner peripheral side excavation blade (3) in opposite directions. When the leading excavation pipe (1) advances by a predetermined distance, a plurality of pilot pipes (not shown) are sequentially added to the rear end. Double digging blade (2)
Due to (3), the crushed bedrock becomes muddy by mixing with the high-pressure water supplied to the excavation section, and both excavation blades (2)
It flows into the space behind the inner peripheral excavation blade from the gap between (3), and is further started by an auger type earth removal device (16) arranged in series in the leading excavation pipe (1) and the subsequent pilot pipe. It is excavated.

By the above operation, the head drilling pipe (1)
When the top excavation pipe (1) reaches the reaching shaft, if it is removed, a pipeline composed of a pilot pipe can be formed between both shafts without cutting the ground. Further, after that, a buried pipe such as a vinyl chloride pipe is connected to the leading pilot pipe in place of the leading drilling pipe (1), and the hydraulic jack provided in the starting shaft is reversely activated to pull the buried pipe by the pilot pipe. Start. Thereafter, each time one pilot pipe is pulled, a new pilot pipe is added to the rear end of the previous pilot pipe in order until the front end of the earliest buried pipe reaches the start pit. And a conduit formed of a buried pipe is formed. This conduit is
For example, it can be used as a pipeline for passing water / sewage, communication, or power cables directly under roads, tracks, embankments, rivers, and the like.

In this embodiment, a case has been described in which a pilot pipe and a buried pipe are sequentially added to the rear end of the leading excavation pipe (1) to form a pipeline in the ground, but the apparatus of the present invention uses a buried pipe. Without being limited thereto, the present invention can be similarly applied to a drilling device for merely drilling a ground. In addition, a rotary drive source (10) is arranged in the leading excavation pipe (1), and only the ring-shaped excavation blade is rotated to make other subsequent pipes (pilot pipe, buried pipe, etc.) non-rotating. The present invention can be similarly applied to a structure in which a rotary drive source is arranged in a starting shaft, and the entire pipe body is rotated to rotate a ring-shaped excavation blade.

[0028]

As described above, according to the apparatus of the present invention, the ground to be excavated can be excavated even with the bedrock, and since it is not a structure in which the crushed pieces are compacted as in the conventional hammer type, even the soft bedrock can be excavated. It becomes possible to excavate smoothly. Therefore, with this single device, it becomes possible to cope with the ground where various strata such as a gravel layer, a boulder layer, and a soft / hard rock layer are mixed.
Construction efficiency can be greatly improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a pipe burying apparatus to which the present invention is applied.

FIG. 2 is a front view of the pipe burying device.

FIG. 3 is an enlarged sectional view of a digging means used in the pipe burying device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Top excavation pipe 2 Ring-shaped excavation blade 3 Inner peripheral side excavation blade 5 Swinging mechanism 7 Excavation head 10 Rotary drive source 35 Excavation means 36 Base 38 Excavation tool (excavation tip) O-O Central axis R Rotation axis 23 Conversion means 24 Pressing member 25 Guide surface 26 Rolling means

Claims (6)

[Claims] 1. A digging in the ground by rotating a ring-shaped digging blade, wherein the tip of the ring-shaped digging blade is on the inner side of the ring-shaped digging blade and on the side of the digging direction. A rotary drilling device, wherein a drilling means having a tilted rotation shaft and a drilling tool provided around the rotation shaft is rotatably mounted. 2. The rotary drilling device according to claim 1, wherein an inner diameter side excavating blade that rotates in a direction opposite to a rotation direction of the ring-shaped excavating blade is disposed on an inner diameter side of the ring-shaped excavating blade. 3. The narrow angle α between the extension of the rotation axis of the excavating means and the central axis of the ring-shaped excavating blade is 55 °.
A rotary drilling device as described. 4. The excavating means comprises a body in the form of a rotating body about a rotation axis, and a plurality of excavating chips protruding from an outer peripheral surface of the body. A rotary drilling device according to any one of the preceding claims. 5. The rotary drilling device according to claim 4, wherein the base is disk-shaped. 6. The rotary drilling apparatus according to claim 4, wherein the diameter of the base is reduced toward the tip of the rotation shaft, and the excavation chips are arranged at a plurality of positions in the axial direction of the rotation shaft.