JPS5914402A - Single crystal diamond tool - Google Patents

Abstract

PURPOSE:To make machining easier, give a longer tool life, and reduce the time required for regrinding by utilizing the anisotropy of diamond when forming a single crystal diamond tool. CONSTITUTION:A single crystal diamond is held on a tool shank in such a way that a crystal face, which is inclined in the direction of a face (110) from a face (100) at an angle alpha deg. of 12 deg., is used as the face, a face (010) side is used for the front flank, and the face (110) side becomes the bottom of the shank. Thus, when the machining is made, in forming the face, from the shank side toward the fron flank side, the machining efficiency is improved about 1.5 times more than in the case of using the conventional longitudinal edge tool which has provided easy machining of faces, while a slick surface is also provided.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a single crystal diamond cutting tool.

In conventional single-crystal diamond cutting tools, the rake face of the cutting tool is a (110) plane, or a plane that is crystallographically equivalent to the (11o) plane, and the front curved surface is a crystallographically equivalent plane to the (100) plane. A vertical cutting tool formed by using the surface perpendicular to the rake face among the surfaces that become circular, and making the rake face's easy-to-process direction (the direction in which wear resistance decreases) and the chip outflow direction coincide. and (110) or (11) on the rake face.
o).

Using a surface that is superior to the crystallographic surface, (11
0) Use a surface that is perpendicular to the rake face among the surfaces that are crystallographically similar to the surface, so that the direction in which the rake face is easy to machine and the direction in which chips flow are perpendicular to each other within the rake face. There was a molded horizontal blade bit.

Due to the directionality of vertical cutting tools, the wear of the rake face is significant and the life of the cutting tool is short, whereas horizontal cutting tools, on the other hand, have a longer lifespan than vertical cutting tools due to their orientation and are often used exclusively. ing.

However, even when using a horizontal cutting tool, it is very difficult to form the tool, the tool life is not very long, and it takes a long time to re-sharpen the tool.

In view of the above-mentioned drawbacks, the present invention was developed based on a clear understanding of the anisotropy of diamond machining, and was developed to enable easier machining when forming a cutting tool, to extend the life of the tool, and to reduce the need for re-sharpening. First, in order to fully understand the present invention, the anisotropy of processing single crystal diamond will be explained with reference to the drawings.

Figure 1 shows the range from the (1o○) plane, the (100) plane and the crystallographically equivalent plane to the (110) plane and the (110) plane and the crystallographically equivalent plane. , which shows the anisotropy of processing in each crystal plane of diamond, with (100) on the horizontal axis.
The angle from the plane or the (10o) plane and the crystallographically superior plane, and the amount of processing are shown on the vertical axis. Figure 2 shows the crystal planes of diamond. In FIG. 1, 1 is a machining characteristic diagram in the direction of arrow B shown in FIG. 2; 1 and 2 are machining characteristic diagrams in the direction of arrow A; and 3 is a machining characteristic diagram in the direction of arrows A and C. As is clear from the figure, the processing amount of each crystal plane exhibits characteristics that vary significantly depending on the direction of processing, and the (100) plane,
Or, from a crystallographically equivalent plane to the (1ω) plane, (11o
) plane, the plane is 5 in the direction of the (110) plane and the crystallographically superior plane.
For crystal planes forming an angle of 17° to 17°, the machining amount in the direction of arrow B in Fig. 2 (Fig. 1, machining characteristic diagram 1) is the (11o) plane, which is the rake face of a conventional vertical cutting tool, or , (11o
) plane and the crystallographically superior plane in the direction in which it is easy to process (Fig. 1, machining characteristic diagram 3). This is explained in 5 above.
It is shown that when a crystal plane forming an angle of 17 degrees is used as the rake surface of a cutting tool and the cutting surface is machined in the direction of arrow B shown in FIG. 2, the surface can be finished more easily and with higher accuracy than before. However, in the crystal plane forming an angle of 5° to 17°, the amount of machining in the direction of the arrow in Figure 2 (machining characteristic line 2 in Figure 1) is the same as the rake face of a conventional horizontal cutting tool (
It is smaller than the amount of processing in the difficult-to-process direction (Fig. 1, processing characteristic diagrams 1 and 2) of the 110) plane or the crystallographically equivalent plane to the (11o) plane. This means that when the crystal plane forming an angle of 50 to 17 degrees is used as the rake face of the cutting tool, and the direction of the arrow shown in Fig. 2 is the direction of chip flow, the wear resistance of the rake face is better than that of the conventional one. It shows that

An embodiment of the present invention will be described in detail below with reference to FIGS. 3 and 4. FIG. 3 shows a top view of the cutting tool, where 4 is a single crystal diamond cutting tool, and 5 is a shank portion that holds the cutting edge of the cutting tool. The tip of the cutting edge is not rounded and is slightly angled, with a front cutting edge angle of 200 degrees and a side edge angle of 0 degrees. FIG. 4 shows an enlarged view of the tip of the cutting edge of the cutting tool, and 6 is a cross section along the WW line (a cross section perpendicular to the rake face), and the forward angle is 10°.

7 is an XX-line cross section (a cross section perpendicular to the rake face);
The forward angle forms an angle of 1o0. 5.8 is the YY line cross section (
The cross section is perpendicular to the side cutting edge and perpendicular to the rake face, and the side angle is 30°.

9 is a ZZ line cross section (a cross section perpendicular to the front cutting edge and perpendicular to the rake face), and the forward angle is oo. The bite rake angle is OO.

When forming this single-crystal diamond cutting tool, the rake face is a crystal plane that is inclined at an angle of 12 degrees from the (100) plane to the (110) plane, with the (010) plane being the forward curved plane. , (1oo) plane side was held in the shank part so that the lower surface of the bite shank. When forming the rake face in this way, if the processing direction is from the shank side to the forward facing side,
Machining efficiency was improved by 1.5 times compared to the conventional vertical cutting tool, which was easy to machine the rake face, and mirror surfaces could be obtained more easily. Taking the machining direction from the shank side to the forward curved surface side means machining in the B direction in Figure 2, and the machining direction is the (1oO) plane or (1oo) plane in the machining characteristic diagram 1 in Figure 1. The angle from the crystallographically superior plane is 1
This corresponds to the case of 2°, where the wear resistance is the lowest.

In addition, when an aluminum cylinder was machined using a single-crystal diamond cutting tool formed in this way, it was found that the time required for crater wear to occur on the rake face of a conventional horizontal cutting tool, which has excellent wear resistance, was It was approximately three times as long, indicating a significant improvement in the tool life. In this case, the flow direction of the chips is direction D in Fig. 2, and the angle from the crystallographically equivalent plane to the (100) plane or (1oo) plane in machining characteristic diagram 2 in Fig. 1 is This corresponds to the case of No. 120, where the wear resistance is the highest.

In addition, in this single-crystal diamond cutting tool, the rake face is 00 to 5 degrees from the (1oo) plane to the (110) plane, and 1
When the angle is set in the range of 7° to 450°, the wear resistance during chip flow is excellent, but when forming the rake face, the angle between 0° and
In the range of 6 degrees, it takes 2 to 7 times as long as in the case of 12 degrees in this example, and in the range of 17 degrees to 46 degrees, it takes 2 to 30 times longer.
It takes twice as much time and is not practical in terms of cost. 00 more
In the range of ~5°, the abrasion resistance is also reduced to 1/12 of the okara as compared to 12° in this example, and the tool life is impractical.

In addition, in this example, the rake face of the cutting tool is (100
Although a plane forming an angle of 12° from the (110) plane in the direction of the (110) plane is used, a plane in the range of 5 to 170 may also be used.

In this example, the (110) plane is still smaller than the (100) plane.
The rake surface is a surface that is 12° in the direction of the surface, the (010) side is formed with a bent surface, and the (1QO) side is the lower surface of the bite shank. It is only necessary that the positional relationship between the lower surface and each surface is crystallographically superior to that of this embodiment.

According to the present invention, the lifespan of the cutting tool is 2 times longer than that of the conventional cutting tool.
The length is more than twice as long, and the rake face can be machined more efficiently, making it possible to provide an inexpensive cutting tool.

[Brief explanation of drawings]

Figure 1 shows the (10Q) plane or (1
From the 00) plane and the crystallographically superior plane, the (110) plane is (
Fig. 2 is an explanatory diagram of a diamond crystal, and Fig. 3 is a single-crystal diamond cutting tool according to an embodiment of the present invention. Cross-sectional view of Figure 4 (A), (B), (C), (
5) and (E) are enlarged cross-sectional views of the cutting edge of the same single-crystal diamond cutting tool. 4... Single crystal diamond bite, 5...
...Shank part. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 2 * 111 < 100 Grapes Figure 3

Claims (1)

[Claims] From the (100) plane of the diamond single crystal plane, (11o
) The surface forming an angle of 5° to 17° in the direction of the cutting tool is the rake surface of the cutting tool, and the (olo) surface is formed with a forwardly bent surface.
100) Single-crystal diamond bit with the bottom side of the bit shank.