JPH0762982A - Cutter bit for shield excavator - Google Patents

Abstract

PURPOSE:To prevent the abrasion of a cutter bit and stabilize the working face ground. CONSTITUTION:A cutter bit main body 1 protruded from the cutter head 3 of a shield excavator A is made of a hard porous material such as an air- permeable ceramic material. A lubricant is fed to the cutter bit main body 1 through a communicating path 8 provided on the cutter head 3 from the inside of the shield excavator A, the cutter bit main body 1 is impregnated with the lubricant, and the lubricant is injected to the working face ground from the surface of the cutter bit main body 1. The excavated sediment and the lubricant are uniformly mixed, the whole working face ground is stabilized, the surfaces of cutting edges 2 fixed to the cutter bit main body 1 are covered with the lubricant, and the abrasion of the cutting edges 2 brought into most violent contact with the working face ground is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved cutter bit projecting from a rotary cutter head of a shield excavator.

[0002]

2. Description of the Related Art When excavating a tunnel with a shield excavator, it is necessary to supply a lubricant such as muddy water between the face and the cutter head in order to stabilize the face ground and reduce the excavation resistance. It is being appreciated. As such a lubricant supply means, a lubricant spray pipe is fixedly provided on the outer peripheral portion of a shield cylinder in which a cutter head is rotatably disposed in the front end opening, and the spray pipe is provided at the central portion of the face face. Generally, a means for supplying a lubricant or a means for forming a lubricant supply hole at the center of the rotary shaft of the cutter head and ejecting the lubricant from the center of the front end of the cutter head through the supply hole is generally adopted.

[0003]

However, according to the above-mentioned lubricant supply means, the lubricant is supplied from only one part of the center or the outer periphery of the cutter head. There is a problem that the mixing with the soil and sand is likely to become uneven, which hinders the retention of the face face and the wear of the drill bit becomes severe.

Therefore, for example, Japanese Patent Laid-Open No. 53-7232
As described in Japanese Patent Publication No. 7, a plurality of lubricant introducing passages radially extending from the front end of a lubricant supplying hole provided at the center of the rotating shaft are provided in the cutter head, and the tip of each lubricant introducing passage is provided. Has developed a lubricant supply means configured to eject the lubricant toward the face of the face. According to this means, it is possible to evenly mix the excavated soil and the lubricant and to stabilize the face face, but the lubricant is supplied between the bit for excavating the face ground and the face of the blade. However, there is a problem in that the bit is still worn out and cannot be used for a long time. An object of the present invention is to provide a cutter bit for a shield excavator that can completely solve such problems.

[0005]

In order to achieve the above object, a cutter bit of a shield excavator according to the present invention is provided on a front surface of a cutter head rotatably arranged at a front end of the shield excavator. In the existing cutter bit, the cutter bit main body is made of a hard porous material, the cutting blade body is fixed to the tip end of the cutter bit main body, and the cutter bit main body is provided on the shield excavator side. It has a structure that communicates with the passage.

As described in claim 2, a hollow passage or a hollow chamber is provided in the cutter bit main body,
The lubricant supply passage may be connected to the hollow passage or the hollow chamber.

[0007]

[Function] When excavating the face ground by propelling the shield excavator and rotating the cutter head, when the lubricant is supplied to the cutter bit from the inside of the machine through the lubricant supply passage, the cutter bit is mainly composed of the porous material. Since it is formed, the lubricating material impregnates the entire cutter bit, and the surface of the cutter bit becomes wet with the lubricating material in a film state, which significantly reduces the wear of the cutting edge that makes the most intense contact with the excavated ground. The life of the cutter bit is improved.

Further, the lubricant exuding from the surface of the cutter bit is poured between the cutter head and the excavated ground,
Spread over the entire face and mix evenly with the excavated soil,
The face surface is stabilized and smooth and efficient excavation is possible.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will now be described with reference to the drawings. In FIGS. 1 and 2, reference numeral 1 is a hard material such as a ceramic material having a gas permeability or a sintered metal, and a myriad of fine particles communicating with each other inside. Mainly composed of a cutter bit formed of a porous material having voids, the tip surface 1a is inclined obliquely upward from the tip edge of the inner side surface 1b to the tip edge of the outer side surface 1c, and the tip surface 1a and the outside The cutting edge 2 is embedded and fixed to the common edge portion having an acute angle with the side surface 1c, and the acute cutting edge is projected forward.

As shown in FIGS. 3 and 4, this cutter bit main body 1 has a large number of protrusions in front of a cutter head 3 rotatably arranged at the open end of the shield cylinder 11 of the shield excavator A. It is stuck to. The cutter head 3 has spokes 3a radially extending from the tip of a rotary shaft 4 integrally fixed to the center of the cutter head 3, and a circular frame fixed between the outer ends of the spokes 3a. The cutter bit base material 1 is composed of parts 3b, and each spoke part 3a
Are arranged at appropriate intervals in the longitudinal direction of the spokes 3a on both sides of the front surface of the.

The cutter bit is attached to the spokes 3a by mounting a pedestal 5 on the bottom of the cutter bit main body 1.
Is fixed by welding or the like, and the pedestal 5 is fixed to the front surface of the spoke portion 3a. The cutter bit main bodies 1 and 1 arranged on both sides of the spoke portion 3a are the cutting blades 2 of each other.
Is directed diagonally outward.

The pedestal 5 and the spoke portions 3a are provided with a lubricant injection hole 6 which communicates with the central portion of the bottom surface of the cutter bit main body 1, and the lubricant injection hole 6 of each cutter bit main body 1 is formed.
Is connected to the lubricant supply passage side provided inside the shield excavator A. That is, the lubricant supply passage 7 is provided at the center of rotation of the rotary shaft 4 of the cutter head 3, and the front end of the lubricant supply passage 7 is passed through the lubricant supply communication passage 8 arranged in the spoke portion 3a of the cutter head 3. It is communicated with the lubricant injection hole 6. The supply start end side of the lubricant supply passage 7 is connected to and communicates with a lubricant supply source (not shown) arranged in the shield excavator A. Reference numeral 9 denotes a partition wall stretched in the shield cylinder 11, which rotatably supports the rotary shaft 4 of the cutter head 3.

Now, the cutter head 3 of the shield excavator A
And excavating the face ground by propelling the shield excavator A with a propulsion jack (not shown) and bentonite through the supply passage 7 from the lubricant supply source,
When the lubricant such as muddy water is supplied, the lubricant penetrates into all the cutter bit main bodies 1 from the injection hole 6 through the communication passage 8 provided in the spoke portion 3a.

At this time, since the cutter bit main body 1 is made of a porous material, the lubricant impregnates the entire cutter bit base material and leaks from the entire surface, and the entire surface including the cutting edge 2 is formed into a film. It flows out between the face of the face and the cutter head 3 while keeping it wet. Further, since the cutter bit main body 1 is provided so as to project at appropriate intervals in the length direction of the spoke portion 3a of the cutter head 3, the lubricant flowing out of the cutter bit main body 1 diffuses over the entire face of the face. It mixes evenly with the excavated earth and sand to stabilize the cutting face and reduce excavation resistance by the cutter head 3, and the surface of the cutting blade 2 of the cutter bit main body 1 is covered with the lubricant in a film shape to form a cutter bit. It reduces the wear and tear of the.

5 and 6 show another embodiment of the present invention, in which a groove-shaped hollow passage 9 is formed in the cutter bit main body 1 so as to reach an appropriate height from the bottom surface. The central portion of the base end is made to communicate with the lubricant injection hole 6, and the lubricant supplied to the injection hole 6 as described above fills the hollow passage 9 and the porous material from the passage 9 It penetrates into the cutter bit main body 1 and pours out from the exposed surface of the cutter bit main body 1 toward the cutting face ground side in the same manner as above.

FIG. 7 shows still another embodiment of the present invention, in which a hollow chamber 9a having an appropriate size is formed inside the cutter bit main body 1 and the hollow chamber 9a is formed through the lubricant injection hole 6.
The hollow passage 9a is formed by forming an intermediate passage 10 communicating with 9a. Once the lubricant is filled in the hollow chamber 9a, the lubricant penetrates into the cutter bit main body 1 and is exposed from the exposed surface of the cutter bit main body 1 in the same manner as above. It is to be poured toward the ground face side.

[0017]

As described above, according to the cutter bit of the shield excavator of the present invention, in the cutter bit protruding from the front surface of the cutter head rotatably disposed at the front end of the shield excavator, The main body of the cutter bit is made of a hard porous material, a cutting blade is fixed to the tip of the main body of the cutter bit, and the main body of the cutter bit is communicated with a lubricant supply passage provided on the shield excavator side. Therefore, while the lubricant supplied to the cutter bit from the inside of the machine through the lubricant supply passage is impregnated into the entire cutter bit main body made of a porous material, it is smoothly poured from the main surface of the cutter bit between the cutter head and the cutting ground. In addition, since the cutter bit has a large number of protrusions in the inner and outer radial directions on the front surface of the cutter head,
The lubricant flowing out from these cutter bits can be diffused over the entire surface of the face of the face and mixed evenly with the excavated soil, and the face of the face of the face can be stably and efficiently excavated.

Further, the lubricant exuding from the surface of the cutter bit makes the surface of the bit base material wet in the form of a film, so that the wear of the cutting edge which comes into the most violent contact with the excavated ground can be significantly reduced, and the cutter can be remarkably reduced. The life of the bit is improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a cutter bit attached to a cutter head,

2 is an enlarged plan view of FIG.

FIG. 3 is a simplified vertical sectional side view of a shield cylinder portion of the shield excavator,

FIG. 4 is a front view thereof,

FIG. 5 is a longitudinal sectional view showing another embodiment of the present invention,

FIG. 6 is an enlarged plan view of FIG.

FIG. 7 is a vertical sectional view showing still another embodiment of the present invention.

[Explanation of symbols]

 A Shield excavator 1 Mainly cutter bit 2 Cutting edge 3 Cutter head 6 Lubricant injection hole 7 Lubricant supply passage 8 Communication passage

Claims (2)

[Claims] 1. A cutter bit projecting from a front surface of a cutter head rotatably arranged at a front end of a shield excavator, wherein the cutter bit main body is formed of a hard porous material and the cutter bit main body is formed. A cutter bit for a shield excavator, characterized in that a cutting blade is fixed to the tip end of the, and the cutter bit main body is communicated with a lubricant supply passage provided on the shield excavator side. 2. A cutter for a shield excavator according to claim 1, wherein a hollow passage or a hollow chamber is provided in the cutter bit main body, and the lubricant supply passage is communicated with the hollow passage or the hollow chamber. bit.