JPH03183891A - Excavation bit - Google Patents

Abstract

PURPOSE:To make it possible to efficiently excavate by providing a guide so that the end thereof approaches the rotation center of the excavation bit nearer than the basic end, and projecting excavation hooks to the peripheral surface from a casing to provide so that they are capable of moving along the guide. CONSTITUTION:In an excavation bit provided at the end of a rotary shaft 5, a guide 18 of excavation hooks 7... and 7A... is so provided that the end thereof approaches the rotation center of the excavation bit nearer than the basic end. The excavation hooks 7... and 7A... projected to the peripheral surface from a casing 6 are provided so that they are capable of moving along the guide 18. According to the constitution, the advancement of the excavation hooks 7... and 7A... is prevented, the excavation hooks 7... and 7A... are not closed, so that excavation efficiency can not be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention provides an excavator suitable for excavating hard 214 Wii.
related to events.

(Conventional technology) The final IJJ person is used as an excavator for ground excavation.

We are developing what is shown in Figures 5 and 6L4.

In FIG. 5 and JS6, 5 is a cylindrical rotating shaft rotated by an excavator (not shown), and 6 is a casing inserted into the vertical or horizontal hole to be excavated by inserting the same rotating shaft. , these are generally constructed in an incremental manner.

Inside the rotating shaft 5, a shaft having a screw blade is inserted into the rotating shaft 5.
It may be installed concentrically with.

A ring 8 is fixed to the tip of the rotating shaft 5, and the ring 8 is in sliding contact with the inner circumferential surface of the casing 6 via a bearing (not shown). 9 is a circumferential axis at the center of the tip of the rotating shaft 5; 10.
Reference numeral 11 denotes plates for mounting three excavating claws radially mounted between the rotary shaft 5 and the cylindrical shaft 9 by welding, and one plate lO is a drilling claw 7 for excavating the inside of the casing 6. The other mounting plate 11 is provided with an excavating claw 7A for excavating a portion extending to the outside of the casing 6.
Provided for installation.

On the other hand, several claws are attached to the plate 10 by block 12 or by welding.

The digging claw 7 has a mounting groove 7b on the inner surface, and the mounting groove 7b
b is fitted onto the flock 12 and removably fixed with bolts 13.

For the other installation, a bracket 15 is attached to the plate 11 so as to be rotatable about the shaft 14, the block 12 is attached to the bracket 15, the groove 7b of the digging claw 7A is fitted into the block 12, and the bolt 13 is attached. By fixing the excavating claw 7A at an angle, the excavating claw 7A is attached at an angle in the same manner as described above. During excavation, the excavating claw 7A opens from the position indicated by the two-dot chain line d to the position indicated by the solid line e due to excavation resistance, and closes to the position indicated by the two-dot chain line d when the excavation bit is reversed.

(Problem to be solved by the invention) However, as shown in Fig. 7, when a water pipe is buried with this excavation bit on its side (in this case, the casing 6 becomes a water pipe and is left underground. ), in the path in which the outermost digging claw 7A descends from the upper position, the digging claw 7A
There was a problem in that the excavator A rotates about the shaft 14 as shown by the arrow R due to its own weight, making it difficult to perform excavation smoothly.

In view of these problems, it is an object of the present invention to provide an excavation bit with a structure that enables efficient excavation even in horizontal hole excavation without the outermost excavation claws closing during excavation.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention provides a drilling bit provided at the tip of a rotating shaft of an excavator, in which the guide of the digging claw is moved from the base end to the tip side. The present invention is characterized in that an excavating claw is provided close to the rotation center of the excavating bit and is movable along the guide and protrudes from the casing.

(Function) Since the drilling bit of the unexploited IJJ has the above-mentioned structure,
Even if the digging claw moves forward due to its own weight and attempts to reduce its diameter, the digging surface prevents the digging claw from moving forward and prevents the digging claw from closing.

(Example) Fig. fJJ1 is a partial side sectional view showing one embodiment of the excavation bit according to the present invention, Fig. 2 is a plane view along E-EpJ thereof, and Fig. 3 is a front view of the excavation bit.

In Figures 1 to 11G3, the same reference numerals as in Figures 5UA to 7 indicate the same constituent members. The plates lO for mounting the excavation claws are arranged radially in a cross shape between the ring 8 at the tip of the cylindrical rotary ring 5 and the central cylindrical shaft 9, and each attachment is at the same position in the radial direction of the plate lO. , 3 (H) are installed in the same structure as shown in FIG. 5 and FIG. Provided corresponding to the claw 7 1
Both ends are attached to the plate IO by welding or bolting. This protection plate 3 is located at a location that substantially matches the rotation locus on the outer peripheral side of the digging claw 7. Further, the tip of each protection plate 3 is located at a position slightly retreating from the tip of each digging claw 7.

As shown in Fig. 4, each mounting block 12 is welded to the plate 1O in an inclined manner so that it precedes the base or tip excavation part in the rotational direction X during excavation, as shown in Fig. 4. It is installed by

Further, the excavating claw 7 has a mounting groove 7b on its inner surface, and the mounting groove 7b is fitted into the block 12 and detachably fixed with a bolt 13. Therefore, the excavating claw 7 is attached such that the center line S of the excavating claw 7 as viewed from the side surface is such that the attached portion precedes the tip when the excavating claw 7 is rotated. The inclination angle θ of the center line S is set to be greater than 0 degrees, and preferably to 45 degrees or less. More preferably, in FIG.
c is a carbide tip fixed to the excavation part, and the carbide tip 7c is attached at any angle suitable for excavation), or the excavation claw 7 is attached so that it is backward in the rotation direction. .

Therefore, in the present invention, the excavating claw 7A for excavating the outside of the casing 6 is attached as follows. Installation is on board 1
0, weld a pair of brackets 16, 17 so that the bracket 17 on the bit tip side is closer to the center of rotation than the bracket 16 on the rotating shaft 5 side, and weld these brackets 16, 17 to
A rectangular guide 18 is installed between them, a rectangular tube 19 is slidably fitted to the rectangular guide 18, an arm 20 is welded to the excavating claw 7A to the rectangular tube 19, and a block 12 is attached to the arm 20. Weld the drilling claw 7A to the block 12 and attach the bolt 1 to the block 12.
3, it is removably attached.

When the excavating claw 7A comes into contact with the excavating surface, the rectangular tube 19 moves along the rectangular guide 18 in the direction of the arrow in FIG. The claw 7A partially protrudes outward from the casing 6, making it possible to excavate the outside. On the other hand, when the digging bit is pulled out as shown by arrow B in FIG. It can be moved back to the D position inside 6, and it can be pulled out. Further, during excavation, the excavating claw 7A bites into the excavated surface and is prevented from moving forward, so that the excavating claw 7A will not be retracted from the casing 6 during excavation.

In addition, as in this embodiment, if the protection plate 3 of each excavation claw 7 is placed along the rotational circumferential direction on the outer circumferential side of each excavation claw 7, if the protection plate 3 of the excavation claw 7 is sunk, a part of the inner circumference may be damaged due to cracks in the bedrock or its own weight. Even if it tries to protrude, it is blocked by the protection plate 3, so that the digging claw 7 is prevented from breaking due to being pressed against the protruding rock.

Further, the excavating claw 7.7A of this embodiment is installed in an inclined structure as shown in FIG. 3, but this is an inclination in the opposite direction to the conventional one. With conventional inclined structures, when excavating sandy rock,
Due to the elasticity of the digging claw and its support, digging of the digging claw,
Either the digging claws 7, 7, and 7 would have repeatedly bounced up, resulting in a decrease in work efficiency, or if the slope was in the opposite direction as in this embodiment, the digging claws 7,
7A does not dig in, the elasticity of the digging claw 7.7A causes the digging claw 7.7A to bite into the excavation surface 4 made of hard rock.
j! This prevents repeated upturns and enables smooth excavation.

The excavating claws 7, 7A may be constructed so that their outer peripheral surfaces are arcuate, or
It is preferable to form it into a twisted shape and attach it as disclosed in Japanese Patent No. 189292. Furthermore, it goes without saying that the structure of the mounting of the digging claws 7, 7A is not limited to the above-mentioned embodiment, and can be modified in various ways.

(Effects of the Invention) According to the present invention, the guide of the excavation claw is provided closer to the tip side or the rotation center side of the excavation bit than the base end thereof,
Since the excavation claw is attached to protrude from the outer periphery of the casing so as to be movable along the guide, even if the excavation claw tries to move forward due to its own weight, the forward movement of the excavation claw is blocked by the excavation surface, and the excavation claw is prevented from moving forward. The claws do not close, making it possible to excavate efficiently.

[Brief explanation of drawings]

IF diagram shows a part 1fr +- (B side view, FIG. 2 is a sectional view taken along line E-E, FIG. 3 is a front view of the excavation bit, and FIG. is a side view showing the state of horizontal hole drilling in this embodiment, FIG. 5 is a front view showing the drilling bit that has been developed before completion, Country 6 is a side sectional view thereof, and FIG. 7 is its problem. It is a partial front view explaining 1: fi* rock mass, 3: protection plate, 5: cylindrical rotation shaft, 6:
Casing, 7.7A: Drilling pawl, 8: Ring, 9: Cylindrical shaft, lO: Mounting is on plate, 12: Nail installation is professional, ・2 and so on 3: Boreto, 16.17: Bracket and 182 Square guide, diagonal tube, 20: Mounted on arm

Claims (1)

[Claims] In an excavation bit provided at the tip of a rotating shaft of an excavator, a guide for the excavation claw is provided so that the tip side is closer to the rotation center side of the excavation bit than the base end thereof, and the casing is movable along the guide. A digging bit characterized by having a digging claw that protrudes further toward the outer periphery.