JPH04193404A - Diamond bite and manufacture method thereof - Google Patents

Abstract

PURPOSE:To enable sharpening of a cutting edge while a chip is fixed to a shank by embedding a diamond chip leaving its cutting face in a metallic sintered body fixed on the front end surface of the shank, while said diamond chip has a trapezoidal cross section with its both sides in a tapered shape and its width increasing gradually from the front end to the rear. CONSTITUTION:A diamond chip C is formed in such a manner that its both sides 1 are formed tapered, its width is gradually increased from the front end to the rear, and the cross section except a flank 2 portion of the front end is formed into a trapezoid. Next, the chip C is put into a molding dies, wholly wrapped up in sintered metal powder, heated and pressurized, so as to form a metallic sintered body M in which the chip C is embedded. Then, the metallic sintered body M is fixed by brazing to a mounting area 3 formed in a step on the front end area of a shank S. Then, the cutting-out process of the front end area of the shank S is performed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a diamond cutting tool (industrial application field), which has a cutting edge made of diamond and is used for various precision finishing machining, sawing concave machining, mirror finishing machining, etc. (hereinafter simply referred to as a cutting tool) and its manufacturing method.

[Conventional technology]

In a conventional cutting tool, in order to secure a diamond tip (hereinafter simply referred to as a tip) to the shank, insert the tip 23 into the insertion hole 22 formed at the tip of the shank 21, caulk around it, and then tighten the roller. There are two methods: attaching the tip 23 to the upper surface of the tip of the shank 21 (see FIG. 9), and pressing the tip 23, which has been brazed and fixed to the upper surface of the tip of the shank 21, with a holding lid 24 (see FIG. 10). The chips were polished and sharpened using a grinding device 11, and the sharpened chips were then fixed to the shank by one of the methods described above. For this reason,
Even if you accurately set the rake angle, relief angle, and other angles of the cutting tool using a polishing device and sharpen the insert, the insert is extremely small relative to the shank, so it may be difficult to attach the insert to the shank. A misalignment occurs. Therefore,
It is difficult to obtain the set bite angle when the tip is fixed to the shank. For this reason, even if each angle of the cutting tool, such as the rake angle, is accurate in the chip state,
If the tool is fixed to the shank, the angle of the tool will vary slightly, making it difficult to produce a large number of tools with exactly the same angle. As a result, the angle of each cutting tool differs slightly, and strictly speaking, the same processing cannot be performed using different cutting tools.

The reason why the tip that has been sharpened is stuck to the shank is because the adhesion strength of the tip to the shank is low, or because of the position of the tip to the shank. This is due to the inability to perform blade machining.

[Problems that the invention attempts to solve]

The main object of the present invention is to increase the adhesion strength of the tip to the shank so that the cutting tool can be machined with the tip fixed to the shank.

[Means to solve the problem]

The means adopted by the present invention to solve this problem is to fix a metal sintered body to the upper surface side of the tip of the shank, and both side surfaces are formed into a tapered shape, and from the tip to the rear end. The width of the chip gradually increases and the cross section of the chip is trapezoidal, and almost the entire part of the chip is buried in the metal sintered body except for the rake face.

[Action of the invention]

The cross section of the tip is trapezoidal, and the tip is held by the metal sintered body, creating a structure that prevents the tip from slipping out of the metal sintered body, increasing the adhesion strength of the tip to the shank. do. This, together with the fact that the tip is fixed to the upper surface of the tip of the shank, allows the cutting tool to be machined with a cutting edge while the tip is fixed to the shank. Therefore, it is possible to provide each cutting tool angle such as a rake angle on the cutting edge of the cutting tool as set. As a result, when manufacturing a large number of cutting tools, the angles of the cutting edge of each cutting tool can be made the same, and strict uniformity of machining can be achieved using different cutting tools.

〔Example〕

Hereinafter, the present invention will be explained in more detail by giving an example in which the present invention is applied to a direct cutting tool.

As shown in FIGS. 1 to 3, the tip C used in the cutting tool according to the present invention has a width that gradually becomes wider from the tip to the rear end, and both sides L thereof are tapered. The cross section is trapezoidal except for the flank 2 at the tip.

The chip C, which has been previously formed into the shape described above, is placed in a mold (
When heated and pressurized with the entire chip C wrapped in sintered metal powder, the entire chip C was buried as shown in Figure 4. A metal sintered body M is obtained. The upper surface side of the tip of the shank S is formed with a step-shaped installation part 3 in which the metal sintered body M can be installed, and the metal sintered body M in which the entire chip C is buried is installed in the shank S. 3 and fixed by brazing (Fig. 5). In this state, the tip of the shank S is machined, and the tip C is machined with a cutting edge based on this shank S. , the desired bite B is obtained (Fig. 6).

Both sides 1 of the chip C are tapered, and
The width gradually increases from the tip to the rear,
Since its cross section is trapezoidal, the chip C is shaped so as to be held by the metal sintered body M, and is almost entirely buried in the metal sintered body M. The shape of the tip C itself has a retaining structure, and when the metal sintered body M is fixed to the tip of the shank S, it is possible to fix only the tip to the upper surface side of the tip of the shank by brazing or the like. The adhesion strength of the tip C to the shank S is significantly increased compared to the above. As a result, after fixing the tip C to the shank S, the tip C is fixed with respect to the shank S.
It is possible to perform cutting edge processing. Therefore, the various angles of the cutting edge of the cutting tool can be processed as set, and when manufacturing a large number of cutting tools, the various angles of the cutting edge and the cutting edge can be made exactly the same.

In the above embodiment, the tip of the shank S is cut out so that the rake face 4 of the chip C is approximately one inch higher than the upper surface 5 of the shank S, and thereby the rake face side of the chip C is polished. There is no buffer between the machine and the machine, so cutting on the rake face side can be done without any problems.

Furthermore, according to the present invention, cutting can be performed on the tip C with the tip C fixed to the shank S, so that both the rake face 4 and the flank face 2 of the cutting tool can be cut as shown in FIG. Can be processed on two sides. That is, when machining with a blade, the entire surface is first roughened, and then only a small area of the tip is re-machined to obtain the desired bite angle.

By processing each surface of the cutting edge of the cutting tool in two steps in this manner, only the small area of the tip can be intensively processed with low grinding resistance, and a sharp cutting edge can be formed.

In the above embodiments, the present invention was explained using a splitting tool as an example, but the present invention can be applied to other tools as long as the tip is fixed to the upper surface of the tip of the shank. .

〔Effect of the invention〕

The cutting tool according to the present invention has a metal sintered body fixed to the upper surface side of the tip of the shank, and both side surfaces are formed in a tapered shape, and the width gradually increases from the tip to the rear end. , the chip has a trapezoidal cross section and is almost entirely buried in the metal sintered body except for the rake face, so that the strength of the chip to the shank is increased and the chip can be attached to the shank easily. Finishing and cutting can be carried out in the fixed state. Therefore, each bite angle provided on the cutting edge of the cutting tool can be precisely and easily processed as set. As a result, the cutting tool angles of the cutting edges of a large number of cutting tools can be made exactly the same, and uniformity of machining with different cutting tools can be realized.

Furthermore, since the cutting process can be performed with the tip fixed to the shank, the tip of the cutting edge can be machined on two sides, making it possible to form a sharp cutting edge.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIGS. 1 to 8 are diagrams for explaining the present invention, and FIG. 1 shows the chip C used in the cutting tool of the present invention.
, FIG. 2 is a front view, FIG. 3 is a right side view, and FIGS. 4 and 5 are center views before and after the metal sintered body M is installed at the tip of the shank S. Longitudinal cross-sectional view, Figure 6 (
A) and (B) are a plan view and a central vertical cross-sectional view of the tip of the cutting tool B after cutting, respectively. Figure 7 is an enlarged cross-sectional view of FIG. 8 is a cross-sectional view of the cutting edge portion where the tip portion is machined on two sides. FIG. 9 and FIG. 1θ are respectively central vertical cross-sectional views of the tip of a cutting tool in which a tip 23 is fixed to a shank 21 by a conventional method. The explanations of the symbols of the main parts constituting the present invention are as follows. B: Diamond bite C: Diamond tip M: Metal sintered body S: Shank 1: Side surface of the tip 2: Flank surface of the tip (blade section) 3: Installation part of the shank 4: Rake surface of the tip (blade section) 5: top of shank

Claims (4)

[Claims] (1) A metal sintered body is fixed to the upper surface of the tip of the shank, and both sides are tapered, and the width gradually increases from the tip to the rear end, so that the cross section is A diamond cutting tool characterized in that almost the entire trapezoidal diamond tip except the rake face is embedded in the metal sintered body. (2) Claim 1 characterized in that the rake face of the diamond tip is slightly higher than the upper surface of the shank.
Diamond bite described in. (3) The diamond cutting tool according to claim 1, wherein the tip of the diamond tip is machined on two sides. (4) The diamond chips are molded into sintered metal with both end faces tapered, the width gradually increasing from the tip to the rear end, and a trapezoidal cross section. The diamond tip is wrapped in powder, heated and pressurized to form a metal sintered body in which almost the entire diamond tip is buried except for the rake side, and the metal sintered body is brazed onto the upper surface of the tip of the shank. A method for manufacturing a diamond cutting tool, characterized in that after the diamond tip is fixed, the shank is machined and the diamond tip is sharpened based on the shank.