JPH0893375A - Excavating tool - Google Patents

Abstract

PURPOSE: To increase the durability of an excavating tool and improve the excavating efficiency, by fitting a holder at the front end of a cylindrical casing tube to eliminate the scattering of blade position of the excavating cutter and fitting the lower groove of the excavating cutter in the holder and fixing therein. CONSTITUTION: A plurality of recesses 6 are provided at the front end of a cylindrical casing tube 2 and a flat plate holder 5 is fixed to fit the excavating cutter. Holders 5 provided in directions perpendicular to lines extended from the center of casing tube 2 are formed so as to be at the same distance from the center. On the other hand, a cutting blade is attached to the front end of excavating cutter and a fixing groove for setting the excavating cutter at the seat at the lower part thereof is provided to set the fixing groove at the seat of the recess 6 of the casing tube 2. In this case, the protrusion of the cutter blade attached to the holder is set to be 3-12mm from the center of holder. The fitting position of excavating cutter is accurately set. The inner blades and outer blades are slantly and oppositely positioned at the inside and outside respectively. When they are used for the reversed rotation, the inner blades and the outer blades are reversed to the outside and the inside respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drilling tool mounted on a front end of a drilling head of a casing tube of an excavator and used as a cutting blade.

[0002]

2. Description of the Related Art As an example of a detachable excavating blade attached to the front end of an excavating head of an excavator, the one shown in FIG. 6 is conventionally known. The removable drilling blade 1 shown in this figure is
A plurality of excavating blade mounting portions 3 are provided at the tip of the casing tube 2, and the excavating blade 1 is mounted on the mounting portions 3. With the rotation of the casing tube 2, the cutting blade 4 provided at the tip of the excavating blade 1 excavates the ground. The casing tube 2 has a hollow cylindrical shape, and its base end is connected to a drive source of an excavator and is rotationally driven about its own axis to perform excavation.

[0003]

By the way, in the above-mentioned conventional detachable excavating blade 1, when the cutting edge 4 is worn, the excavating blade 1 is pulled out from the mounting portion 3 and replaced. Since the position of the attachment part 3 attached to the blade 2 is not constant and varies, when the new excavating blade 1 is attached, the edge position of the cutting edge 4 becomes more and more uneven, and the extra excavating force is exerted on the protruding cutting edge 4. As a result, the cutting edge 4 is worn out significantly and the tool life is shortened, so that there is a problem in that the excavation efficiency is extremely poor and the excavation blade 1 must be replaced at an early stage. The present invention has been made in view of the above circumstances, and is a case in which the drilling blade 1 is mounted.
Accurately setting the position of the holder 5 within the recess provided in the thing tube to reduce the variation in the position of the cutting edge 4 of the excavating blade 1 to extend the cutting edge life and improve excavation efficiency and excavation. The blade tip shape of the blade 1 is one casing tu
The cutting edge for the inner blade was slanted inward while the cutting edge for the inner blade was slanted inward and the outer blade was slanted outward so that the cutting edge position of the tip cutting blade 4 was displaced from the center position so that it could be replaced according to the application. Since the drilling tool is formed and the cutting edge positions of the respective cutting blades 4 are formed to be symmetrical positions, the required inner diameter or outer diameter can be obtained regardless of which drilling blade is mounted. When it is used for reverse rotation, it can be used by changing the mounting position and mounting the inner and outer blades in opposite directions, so it can be applied to multipurpose construction of forward and reverse rotation with one casing tube. The purpose of the present invention is to provide an excavating tool.

[0004]

DISCLOSURE OF THE INVENTION A drilling tool of the present invention is a parallel plate-shaped holder for mounting a drilling blade 1 in the recesses by providing recesses at a plurality of positions at the tip of a cylindrical casing tube 2. -5 is attached, the mounting position of the holder is accurately set, and the cutting blade 4 of the excavating blade is attached to the holder-5.
Is installed so that there is no variation in the position of
5, a hole 7 for inserting a pin is provided in the central portion, and a lower groove 8 of the excavating blade 1 provided with a cutting blade 4 at the tip is attached to the holder 5 and fixed with a pin. .

[0005]

With the above-described structure, the holder 5 provided in the concave portion of the tip of the casing tube 2 is accurately attached, so that the position of the cutting blade 4 of the excavating blade 1 attached to the holder 5 can be adjusted. It has the advantages of less variation, improved drilling efficiency, and significantly extended tool life.
Further, since the excavating blade 1 is formed according to the purpose, it has an advantage that it can be applied to multipurpose construction.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will now be described in more detail with reference to the drawings. FIGS. 1 to 5 show an embodiment of a drilling tool according to the present invention, which is a cylindrical hollow casing.
A plurality of recesses 6 provided with parallel plate-shaped holders 5 for mounting the excavating blade 1 are provided at the tip of the thin tube 2, and the parallel plate-shaped holders 5 have a cylindrical shape. It is provided at the center of the wall thickness T of the thing tube 2 and is provided at a right angle to the line extending from the center point of the cylindrical casing tube to the outside diameter direction, and each holder. -5 are provided so as to be at the same position from the center point. A hole 7 for inserting a pin is provided at the center of each holder-5. In the method of forming the parallel plate-shaped holder 5, the concave portion 6 may be formed on the tip end surface of the hollow cylindrical casing tube 2 and a flat plate may be attached in the concave portion by welding, or an H-shaped holder. The holder may be preformed and attached by welding. On the other hand, the excavating blade 1 attached to the holder-5
As shown in FIG. 4, the whole is made of a steel shank, a cutting edge 4 made of cemented carbide is provided at the tip thereof, and an engaging groove 8 for attaching to the parallel plate-shaped holder 5 is provided at the lower part thereof. Is provided. A pin insertion hole 9 is provided in the center of the side surface of the engagement groove 8 to prevent the excavation blade 1 mounted on the holder 5 from falling off. Drilling blade 1
The cutting blade 4 is formed by forming the excavating blade 1 for the inner blade and the outer blade by shifting the tip edge portion from the center position. Drilling blade for inner blade 1
The shank portion is inclined inward, and the outer cutter blade 1 is formed by inclining the shank portion outward. The tip edge portion of the cutting blade 4 is provided with the blade edge positions of the inner blade and the outer blade at respective target positions from the center of the engagement groove 8. The cutting blade 4 for the inner blade and the outer blade may be used as a staggered blade or as a single blade, and when used for reverse rotation excavation, install the inner blade and the outer blade in reverse. You can use it. In addition, the protrusion amount of the cutting edge 4 is 3 in order to reduce wear of the holder.
Set in the range of mm to 12 mm.

[0007]

As described above, the excavating tool of the present invention has a parallel plate-shaped holder for mounting the excavating blade 1 by providing a plurality of concave portions 6 at the tip of the cylindrical casing tube 2. -5 is attached to the cylindrical casing tube 2
Holders provided at positions orthogonal to the line extending from the center point of the holder are formed so as to be at the same position from the center point, and a hole 7 for inserting a pin is provided at the center of the holder.
On the other hand, a cutting blade 4 is provided at the tip of the excavating blade 1, and an engaging groove 8 for mounting the seating portion 5 is provided at the lower portion thereof.
In addition, a hole 9 for inserting a pin is provided in the center of the side surface of the engaging groove 8, and the engaging groove 8 of the excavating blade 1 is attached to the seating portion 5 of the recess 6 of the cylindrical casing tube 2. Since the excavation tool fixed with the retaining pin is formed, the attachment position of the excavation blade 1 attached to the front end of the cylindrical casing tube 2 is accurately set, so that the variation in attachment is eliminated. With the advantage that the life is greatly extended, the excavating blade 1 to be attached is attached to the excavating blade for the inner blade and the excavating blade for the outer blade from the center position of the holder to the inner blade to the inner side and the outer blade to the outer side at the target positions, respectively. Since it is inclined, it has an advantage that when used for reverse rotation, the inner blade can be inverted and the outer blade can be inverted.

[Brief description of drawings]

FIG. 1 is a front view of a cylindrical casing tube equipped with a drilling tool according to the present invention.

FIG. 2 is a front view of a recess in which a parallel plate-shaped holder is provided at the front end of the casing tube.

FIG. 3 is a side view in which a cutting blade is attached to the front end of the casing tube.

FIG. 4 is a side sectional view in which a drilling blade having a cutting blade is mounted inside a parallel plate-shaped holder at the front end of the casing tube.

FIG. 5 is a bottom cross-sectional view in which a drilling blade having a cutting blade is attached to the outside of a parallel plate-shaped holder at the front end of the casing tube.

FIG. 6 is a side view showing a conventional cutting blade attached to the front end of the casing tube.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Excavation blade 2 Cylindrical casing tube 3 Attachment part 4 Cutting edge 5 Parallel plate-shaped holder 6 Recessed part 7 Pin hole provided in the center part of the seating part 8 Engagement groove provided in the lower part of the excavation blade 9 A pin hole provided at the center of the side surface of the engaging groove of the drilling blade.

Claims (6)

[Claims] 1. Parallel plate-shaped holders for mounting excavating blades are respectively installed in recesses provided at a plurality of positions at the tip of a cylindrical casing tube, and the holders extend radially from a center point. It is provided at a position perpendicular to the line and at the center of the wall thickness of the casing tube.A hole for inserting a pin is provided at the center of the holder, while a cutting edge is provided at the tip of the excavating blade. A holder for the cylindrical casing tube is provided in the lower part of which an engaging groove for mounting on the holder is provided, and a hole for inserting a pin is provided in the center thereof.
An excavating tool, characterized in that the engaging groove of the excavating blade is attached to and fixed by a pin for retaining. 2. The excavating tool according to claim 1, wherein the cutting edge portions of the excavating blades mounted on the flat plate-shaped holder provided on the cylindrical casing tube are arranged in a staggered pattern. 3. A drilling blade mounted on a flat plate-shaped holder provided on a cylindrical casing tube, wherein an inner blade or an outer blade is installed at an arbitrary position. Drilling tool. 4. An inner blade inner diameter and an outer blade outer diameter constituted by an excavating blade mounted on a flat plate-shaped holder provided on a cylindrical casing tube are required even if the excavating blade is arbitrarily mounted. The excavating tool according to claim 1, wherein the holder is installed so as to obtain an inner diameter of the inner blade and an outer diameter of the outer blade. 5. An excavating blade mounted on a flat holder provided on a cylindrical casing tube has a shank portion provided with a cutting blade, the inner blade is inclined inward, and the outer blade is inclined outward. The excavating tool according to claim 1, claim 2, claim 3, or claim 4. 6. A protrusion amount of a cutting edge of an excavating blade mounted on a flat plate-shaped holder provided on a cylindrical casing tube,
The excavating tool according to any one of claims 1 and 2, 3 and 4, wherein the center position of the flat plate holder is set within a range of 3 mm to 12 mm.