JPH0565789A - Excavating tool - Google Patents

Abstract

PURPOSE:To enable a sufficient shearing force to be obtained, and enable excavated scraps to be efficiently avoided. CONSTITUTION:On the center of a device 2, an exhaust hole 7 to be extended in the axial direction is formed, and through blocks 11, penetration holes 18 to be extended in the axial direction and to be opened on the tip end surfaces of the blocks 11 are board. On the device 2, a communicating hole 22 to be communicated with the exhaust hole 7 and the penetration holes 18 is formed. Besides, the cutting edge section 13b of an edge body 13 is turned to a side in the rotational direction of the device 2. Accordingly, when the device 2 is rotated, and excavation is performed, they by the cutting edge section 13b, a sufficient shearing force is worked on the wall surface of an excavated hole, and it is properly worked for excavation with rotation only. Besides, as compressive air is blown out of the penetration holes 18, excavated scraps excavated by the edge bodies 13 erected on the tip end surfaces of the blocks 11 can be efficiently avoided, and the cooling effect of the edge bodies 13 is also increased, and so the edge bodies 13 can be prevented from being abraded or damaged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excavating tool used when excavating the ground or soil in various types of anchor construction, various drilling well construction, various foundation pile hole construction, etc. In addition, the present invention relates to a device capable of efficiently removing excavation waste.

[0002]

2. Description of the Related Art Conventionally, as one of excavating tools for excavating the ground, earth and sand, the one disclosed in Japanese Patent Laid-Open No. 63-11789 is known. This drilling tool is shown in FIGS.
As shown in 0, on the bottom surface of the device 2 which receives the impact force of a hammer (not shown) and the rotational force of the hammer cylinder 1,
Two shaft holes 2a, which are point-symmetric with respect to the center of the device 2,
2b are formed, the block shafts 3a and 3b are fitted into the respective shaft holes 2a and 2b so that the block shafts 3a and 3b are rotatable around the shafts and do not come off, and the diameters of the device 2 are attached to the tip ends of the block shafts 3a and 3b. Blocks 5a and 5b having a substantially semi-circular shape with substantially the same diameter as the above and having a large number of blades 4 planted on the tip surface are provided with their straight end surfaces 6a and 6b facing each other, and the block shaft 3a, At the position of 3b, when the device 2 rotates in the excavation direction, one end of each of the blocks 5a and 5b both protrudes from the outer peripheral surface of the device 2 by a predetermined excavation amount, and at that time, Straight end face 6 of both blocks
The a and 6b are eccentric from the center of the device 2 so that they abut each other.

In the above excavation tool, when the device 2 is rotated in the excavation direction X by the hammer cylinder 1, the blocks 5a and 5b receive excavation resistance and the block shaft 3 moves.
While rotating around a and 3b as an axis, one ends of the straight end surfaces 6a and 6b of the blocks 5a and 5b protrude from the outer peripheral surface of the device 2 by a predetermined amount, and part of the straight end surfaces 6a and 6b abut each other. Rotation of the blocks 5a, 5b is stopped, and in this state, the blocks 5a, 5b receive the rotational force of the device 2, excavate the ground by the blades 4 ..., and further advance the ground by the impact force of the hammer. To do.

At this time, in the earth and sand excavated, the compressed air discharged when the hammer piston falls in the hammer cylinder 1 is blown out from the air holes 8a and 8b provided in the bottom surface of the device 2 to cause the excavation tool. After being separated from the tip, it moves to the inside of the excavation pipe 9 via the discharge groove 9a provided in the device 2, and is further discharged from there.

[0005]

By the way, since the above-mentioned excavating tool excavates by the impact force of impact rather than the rotational force, the blade bodies 4 provided on the blocks 5a, 5b have bottom surfaces of the excavation holes. Generally, it has a curved surface convex toward the side. On the other hand, when excavating rocks,
It is known that cutting by shearing requires less force during digging than crushing by impact force, and a high digging speed can be obtained with a small load.

In order to perform the excavation by such shearing, the excavating tool may be rotated, but in the above excavating tool, the blade body 4 ...
Has a convex curved surface toward the bottom side of the drill hole,
Even if the drilling tool was rotated, a sufficient shearing force could not be obtained, and it was not suitable for excavation by only the rotating force.

Further, in the above drilling tool, air holes 8a, 8b for blowing out compressed air are formed on the bottom surface of the device 2, and the block 5a is provided between the air holes 8a, 8b and the drilling surface to be drilled. , 5b, and the air holes 8a, 8b are not provided in the central part of the device 2, that is, near the central part of the excavation hole to be excavated, so that excavation debris is not efficiently removed. There was a drawback.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a drilling tool capable of obtaining a sufficient shearing force and efficiently removing excavation debris.

[0009]

In order to achieve the above object, an excavating tool according to the present invention is provided on a bottom surface of a device that receives a rotational force, in a point symmetry with respect to the center of the device, around a block axis. A block that is rotatably fitted and has a substantially semi-circular shape with the same diameter as the device at the tip of each block shaft and has a large number of blades on the tip surface of each block. Are provided to face each other, the position of the block axis, when the device is rotated in the excavation direction, one end of each of the two blocks both project a predetermined amount of excavation from the outer peripheral surface of the device, and In a drilling tool that is eccentric from the center of the device so that the straight end surfaces of both blocks come into contact with each other,

An exhaust hole extending in the axial direction is formed at the center of the device, and a through hole extending in the axial direction and opening at the tip end surface of the block is formed in the block, and the exhaust hole and the through hole are formed in the device. Is formed, and the cutting edge portion of the blade body is directed toward the rotation direction side of the device.

[0011]

In the excavating tool of the present invention, since the cutting edge portion of the blade body faces the rotation direction side of the device, when the device is rotated and excavation is performed, the cutting edge portion cuts the excavation hole. A sufficient shearing force acts on the wall surface, so that excavation by the rotating force can be effectively performed. In addition, the exhaust hole into which the compressed air flows and the through hole formed in the block and opening to the tip end surface of the block are connected by the communicating hole, and the compressed air is blown out from the through hole, thereby planting the end surface of the block. The drill bits can be efficiently removed by the installed bit.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the excavating tool of the present invention will be described below with reference to FIGS. 1 to 7. The excavating tool shown in these figures is the same as the conventional excavating tool shown in FIGS. Since the excavation part is mainly different, only this part will be described, and description of other configurations will be omitted. Since the excavating tool of this embodiment excavates only by the rotational force, there is no hammer cylinder as in the conventional example, and the device 2 is simply rotatably attached to the lower end of the cylindrical pipe to prevent the device 2 from coming off. The device 2 has a structure in which the device 2 is rotated by a rotary rod or the like. In addition, FIG.
The blade 13 is omitted in FIGS. 6 and 8.

1 to 3 show a first embodiment, in which reference numeral 10 denotes an excavation portion. This excavator 10 is block 1
1 and a block shaft 12 that supports the block 11 as main components. Note that FIG. 3, FIG. 5, and FIG.
In, the blade body 13 is omitted.

The block 11 is a plate having a substantially semicircular shape in a plan view, and an outer peripheral surface of an upper surface thereof has an inclined surface 11a which gradually inclines toward the base end side in the axial direction of the device 2 as it goes outward. Are formed, and a large number of blades 13 are provided on the inclined surface 11a and the upper surface of the block 11. The blade 13 has a substantially L-shaped cross section,
Cross-section L, one end of which is fixed to the tip surface of the block 11 by implantation.
It is composed of a character-shaped protrusion 13a and a cutting edge 13b joined to the other end of the protrusion 13a. This blade 13
Reference character b is a disk-shaped one, and has an integrally laminated structure of a cemented carbide substrate 13c and a polycrystalline diamond layer 13d. Then, each blade 13 has a diamond layer 13d serving as a blade surface directed toward the rotation direction side of the device 2.

Further, as shown in FIG. 3, an exhaust hole 17 extending in the axial direction is formed in the center of the device 2.
The exhaust hole 17 is opened in the base end surface of the device 2,
Compressed air is introduced from this opening by a compressor provided above the pipe to which the device 2 is attached. On the other hand, each of the blocks 11 is formed with a through hole 18 which extends in the axial direction and opens at the tip surface of the block 11.

Further, the device 2 is formed with a hole 19 extending orthogonally to the tip of the exhaust hole 17, and extends from both ends of the hole 19 toward the tip of the device 2.
Further, a hole 20 penetrating the block 12 is formed. These holes 20 and the through holes 18 have the same coaxial diameter and are connected at the boundary surface 21 between the block 11 and the device 2. Then, the holes 19 and 20 are
A communication hole 22 that connects the exhaust hole 17 and the through hole 18 is formed.

In the excavating tool as described above, when the device 2 is rotated in the arrow X direction, the block shaft 12 and the block 11 are integrally rotated with the device 2 in the same direction. When the block 11 rotates in the excavation direction, the block 11 rotates about the block shaft 12 due to excavation resistance, one end of the straight upper end surface of the block 11 projects from the outer peripheral surface of the device 2, and this portion functions as an outer peripheral blade.

When the block 11 rotates,
The right upper end surfaces 11a of the blocks 11 come into contact with each other, and they function as stoppers to restrict further rotation of the blocks 11. In this state, the block 11 receives the rotational force of the device 2 and excavates the ground by the blade 13.

At this time, the air compressed by the compressor or the like flows in from the exhaust hole 17 and blows out from the through hole through the communication hole 22 to remove the excavated chips.
Since this through hole is formed in the block 11 and opens at the tip end surface of the block, and is located near the center of the excavation hole, it was excavated by the blade 13 planted at the tip end surface of these blocks 11. Since excavation debris can be removed efficiently, and the cooling effect of the blade body 13 is increased as compared with the conventional case, wear and loss of the blade body 13 can be prevented.

Further, since the diamond layer 13d of the cutting edge portion 13b of the blade body 13 faces the rotation direction side of the device 2, when the device 2 is rotated and excavated, the diamond layer 13d excavates a drill hole. Since a sufficient shearing force acts on the wall surface of the, the excavation only by rotation can obtain a high excavation speed with a small load.

4 and 5 show a second embodiment. On the straight end surface 11b of the block 11 shown in these figures, a notch 25 is formed by notching this portion into a semi-cylindrical shape. These cutouts 25 have the same radius, and the device 2 rotates in the excavation direction so that the block 11
One end of the straight end surface 11b of the device projects from the outer peripheral surface of the device 2, and when the blocks 11 stop rotating due to a part of the straight end surface 11b contacting each other, the through holes 26 are formed so as to face each other. To form. The through hole 26 penetrates the block 11 on the rotation axis of the device 2 and opens at the tip surface of the block 11.

Further, the device 2 is formed with a communication hole 27 which connects the exhaust hole 17 and the through hole 26. The structure of the blade 13 is the same as that of the first embodiment. Also in the excavating tool of this embodiment, the through hole 26 is formed in the block 11 and the block 1 is formed as in the first embodiment.
Since it is opened at the tip surface of No. 1 and is located in the vicinity of the central portion of the excavation hole, it is possible to efficiently remove the excavated debris excavated by the blade body 13 planted at the tip surface of these blocks 11. At the same time, the cooling effect of the blade body 13 is increased as compared with the conventional case, so that the blade body 13 can be prevented from being worn or broken. Further, it is needless to say that a high excavation speed can be obtained with a small load even when excavating only by rotation.

6 and 7 show a third embodiment. On the straight end surface 11b of the block 11 shown in these figures, notch portions 28a, 29a formed by notching this portion in a semi-cylindrical shape.
Are formed so as to be separated from each other by a predetermined distance and are gradually inclined toward the device 2, and the other straight end face 11b is similarly cut out in a semi-cylindrical shape. The notches 28b and 29b are formed so as to be separated from each other by a predetermined distance and are inclined so as to gradually approach each other toward the device 2. These notches 28a,
28b and 29a, 29b are of the same radius,
The device 2 rotates in the excavation direction, one end of the straight end surface 11b of the block 11 projects from the outer peripheral surface of the device 2, and parts of the straight end surface 11b come into contact with each other to stop the rotation of the block 11. At this time, the through holes 3 face each other.
0, 31 are formed. Then, the through holes 30 and 31 penetrate the block 11 through a site symmetrical with respect to the rotation axis of the device 2 and open at the tip surface of the block 11.

Further, the device 2 is formed with a communication hole 32 which connects the exhaust hole 17 and the through holes 30 and 31. The structure of the blade 13 is the same as that of the first embodiment. Also in the excavating tool of this embodiment, the same effect as that of the first embodiment can be obtained.

[0025]

As described above, according to the excavating tool of the present invention, since the cutting edge portion of the blade body faces the rotation direction side of the device, when excavating by rotating the device, A sufficient shearing force acts on the wall surface of the drill hole by the cutting edge portion. Therefore, it is suitable for excavation only by rotation.

Further, since the exhaust hole into which the compressed air flows and the through hole formed in the block and opening to the tip end surface of the block are connected by the communication hole, the compressed air is blown out from the through hole. Since excavated chips excavated by the bit planted on the tip surface of the bit can be efficiently removed, and the cooling effect of the bit is increased as compared with the conventional case, wear and breakage of the bit can be prevented.

[Brief description of drawings]

FIG. 1 is a bottom view of a drilling tool according to a first embodiment of the present invention.

FIG. 2 is a bottom view of the excavating tool according to the first embodiment of the present invention.

FIG. 3 is a half-section view of a device with blocks attached.

FIG. 4 is a bottom view of the excavating tool according to the second embodiment of the present invention.

FIG. 5 is a half-section view of a device with blocks attached.

FIG. 6 is a bottom view of the excavating tool according to the third embodiment of the present invention.

FIG. 7 is a half-section view of the device with blocks attached.

FIG. 8 is a sectional view of a main part of a conventional excavating tool.

FIG. 9 is a bottom view of a conventional excavating tool in a reduced diameter state of an excavating portion.

FIG. 10 is a bottom view showing the diameter-expanded state of the excavation portion of the conventional excavation tool.

[Explanation of symbols]

 2 device 10 excavation part 11 block 12 block shaft 13 blade body 13b cutting edge part 13c cemented carbide substrate 13d diamond layer 17 exhaust hole 18, 26, 30, 31 through hole 22, 27, 32 communicating hole

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasushi Kihara 1-297 Kitabukurocho, Omiya City, Saitama Prefecture Mitsubishi Materials Corporation Central Research Laboratory

Claims (1)

[Claims] 1. A bottom surface of a device that receives a rotational force is rotatably fitted around a block shaft in a point-symmetrical manner with respect to the center of the device, and the device is attached to the tip end of each block shaft. A block having a substantially semi-circular shape with the same diameter as the diameter and provided with a large number of blades on the tip surface is provided with the respective straight end surfaces facing each other, and the position of the block shaft is set in the excavating direction by the device. When rotated, one end of each of the two blocks is projected from the outer peripheral surface of the device by a predetermined amount of excavation, and at that time, the straight end surfaces of both blocks are eccentric from the center of the device. In the drilling tool, the exhaust hole extending in the axial direction is formed at the center of the device, and the through hole opening in the tip end surface of the block is formed in the block. The exhaust hole and the through hole to form a communication hole communicating with the chair, and further,
An excavating tool, wherein a cutting edge portion of the blade body is directed toward a rotation direction side of the device.