JPH056003Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rotary cutter in which diamond chips formed from a diamond tool material are arranged so as to extend substantially parallel to the flank face of each blade tip, and particularly to the structure of the cutting edge portion of the diamond cutter.

As shown in FIGS. 1 and 2, a rotary cutter 1 using a diamond chip 2 consisting of a diamond layer 4 and a cemented carbide layer 5 and having the diamond layer 4 on the entire surface of the rake is conventionally used. Are known. In the diamond tool material providing the diamond chip 2, the diamond layer is backed by a cemented carbide layer having the same surface area as the diamond layer under high temperature and high pressure. In order to use this as a cutting edge, the diamond tool material is cut into a rectangular shape as shown by the solid line in FIG.
The tip is then polished as shown by the broken line and fixed to the blade body 3 by brazing or screwing. When bonding with solder, since the wax does not get on the diamond layer 4, the lining of the cemented carbide layer 5 and the cutter body B
(Figure 2).

In this case, since the diamond layer 4 is very fragile, the cemented carbide layer 5 is always bonded to each cutting edge so as to reinforce the diamond layer 4. Taking a rotary cutting tool as an example, the diamond chip material 6 has a diamond layer 4 on the entire rake face.
is soldered. Therefore, the diamond layer 4
is fixed so as to extend entirely parallel to the rake face of the cutter body 3, that is, in the radial direction of the cutter (FIG. 2).

However, when manufactured using this method,
As shown in FIG. 2, all of the rake faces are joined so that the diamond layer 4 is formed, and a diamond tool material in which the diamond layer 4 is present over a wide area must be used.

As a result, it had the disadvantage of being extremely expensive. Moreover, even though the life of the diamond cutting edge is approximately 100 times longer than that of cemented carbide, the life of the diamond cutting edge is completely amortized due to fatigue of the blade body and the brazed layer due to use. It has the disadvantage that it breaks before it can be used, so even though expensive diamonds were used, the blade had to be thrown away while the diamond still had a useful life.

The inventor of the present invention has developed a new device as shown in FIG. 4 aimed at solving these drawbacks (Utility Model Application No. 14804/1983). In other words, the invention was developed based on the fact that the breakage of the blade body and brazed layer due to fatigue roughly coincides with the period during which a diamond cutting edge can be used after being re-polished several times. By using only the minimum necessary amount of extremely expensive diamond tool material, the cutting tool has the same cutting performance as conventional products, but is cheaper and has a diamond cutting edge.

However, in this tool, which has a diamond layer 7 having a roughly triangular cross section at the tip end, the diamond tool material is first coated with a diamond layer 7 on the upper surface and a cemented carbide layer 8 below, as shown by the solid line in FIG. Diamond chip material 9
Then, approximately half of the diamond layer 7 of the material 9 was dropped diagonally at an angle α as shown by the broken line in FIG. 5, to form a diamond chip 10 as shown in FIG.

For this reason, the polishing work of cutting the diamond chip material 9 and removing the diamond layer 7 from there to the broken line area in FIG. 5 was labor intensive. In order to eliminate such drawbacks, the present invention aims to provide a rotary cutter as described above that facilitates processing of diamond layers by reducing the volume dropped during polishing and significantly reducing the polishing time. do.

The present invention will be described below.

Figure 6 shows a conventionally known diamond tool material 20.
It is. 22 is a diamond layer, and 24 is a cemented carbide layer. In the present invention, the diamond tip material 26 is formed by cutting the diamond tool material 20 obliquely at an inclination angle α. By cutting in this manner, the work of dropping the diamond layer 7 to the angle α in the prior art design shown in FIG. 5 is completely unnecessary. FIG. 7 shows an example of a cutting blade to which a diamond chip 28 made of the diamond chip material 26 formed in this manner is attached.

According to the invention, the diamond layer 22 extends parallel to the flank surface of the cutting edge and has approximately the same thickness. Therefore, more volume of the diamond layer 22 remains on the cutting edge than in the case shown in FIG. 4, and if the cutting angle α shown in FIG. Polishing time is shortened, and the wear of the grinding wheel is also reduced. In addition, as shown in FIG. 7, the diamond layer 22 can be mounted so that a radially inward portion of the back surface 32 facing the rake surface 30 is supported by the cutter body 34.

As described above, in the present invention, the workability of the diamond layer 22 is significantly easier than in the prior invention, and the labor required for polishing work can be greatly reduced.

The diamond chip material according to the present invention can be applied not only to circular saw cutters, routers, and bits, but also to various cutlery for all purposes, and can be said to be extremely useful. As mentioned above, the present invention significantly simplifies the work of polishing the cutting edge compared to the earlier invention, and in addition, compared to conventional diamond-tipped cutters, diamond tool materials can be used more sparingly. Its cutting performance is exactly the same as that of blades made using conventional designs, and its long life means that even with a small number of re-sharpenings, the number of machining operations can be sufficiently increased. This can be said to be a useful idea.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a known rotary cutting tool, FIG. 2 is an enlarged view of the cutting end of a known diamond cutting tool,
Fig. 3 is a diagram showing the shape of a known tip material cut from a diamond tool material, and Fig. 4 is a diagram similar to Fig. 2 of the diamond cutter of the earlier application, which was invented by the same inventor as the inventor of the present invention. , Fig. 5 is a diagram showing the shape of the diamond chip material constituting the diamond cutting tool of Fig. 4, Fig. 6 is a diagram showing the diamond tool material forming the cutting tool of the present invention and the diamond chip material formed from it, FIG. 7 is a view similar to FIGS. 2 and 4 in which a diamond chip made of the diamond chip material of FIG. 6 is attached. Explanation of symbols, 20...Diamond tool material,
22...Diamond layer, 24...Cemented carbide layer,
26...Diamond chip material, 28...Diamond chip, 30...Rake face, 32...Back surface, 34...Blade body, α...Cutting angle.

Claims (1)

[Claims for Utility Model Registration] A rotary cutter consisting of a cutter body 34 that rotates by attaching the center portion to a rotating shaft, and a plurality of diamond chips 28 held on the outer peripheral edge portion of the rotating cutter body 34. The diamond chip 28 is composed of a diamond layer 22 located radially outward of the rotary cutter, and a cemented carbide layer 24 located radially inward, and the diamond layer 22 includes: It constitutes the entire flank surface over the entire blade thickness of the cutter, extends generally parallel to the flank surface and has the same thickness, and forms a radially inner part of the back surface 32 of the diamond layer 22. The part is the cutter body 34 of the rotary cutter.
A rotating blade characterized by being held by.