JPS6029367Y2 - Composite throw-away tip - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a composite indexable insert in which a polycrystalline material such as cubic boron nitride or diamond is fixed to an alloy made of cemented carbide, steel, ceramic, etc. as a cutting edge.

BACKGROUND ART Conventionally, as this type of indexable tip, a structure as shown in FIGS. 1 and 2, or a structure as shown in FIGS. 3 and 4 is known.

That is, the indexable insert 1 shown in FIGS. 1 and 2 has a seat 3 formed at one corner of the base metal 2, which is a roughly triangular flat plate, and a flat plate forming the cutting edge on the seat 3. The polycrystalline body 4 is placed on a bottom plate 9 so that its scoop surface 5 coincides with the upper surface 6 of the base metal 2 and the nipped surface 7 coincides with the circumferential side surface 8 of the base metal 2.
It is fixed by brazing or the like through the.

In addition, the indexable insert 11 shown in FIGS. 3 and 4 has a seat 13 formed at the corner of a base metal 12, which is a flat plate body having a substantially triangular shape and a trapezoidal cross section, and a cutting edge portion is formed in this seat 13. The flat plate-shaped polycrystalline body 14 is
The base metal 12 is fixed by brazing or the like via a bottom plate 19 so that the ribbed surface 17 coincides with the upper surface 16 of the base metal 12 and the circumferential side surface 18 of the base metal 12.

Incidentally, the tooth surface 5 in the indexable insert 1 shown in FIGS. 1 and 2 is parallel to the bottom surface 10 of the base metal 2, and the angle between the tooth surface 5 and the nib surface 7 is a right angle. and the indexable tip 11 shown in FIG.
The rake surface 15 is parallel to the bottom surface 20 of the base metal 12,
The angle formed by the rake surface 15 and the nib surface 17 is set to a predetermined angle of 90° or less, but when these indexable tips 1 and 11 are attached to an appropriate holder (not shown) and used as a cutting tool. The rake angle and nip angle of the cutting tool are determined by the chip mounting seat formed on the holder used.

However, due to the characteristics of using indexable chips, chip mounting seats are specified by various standards because compatibility between chips or with a holder is important, and the polycrystalline bodies 4 and 14 are In view of the above requirements, they have a certain shape, and the scoop surfaces 5, 15 of the indexable inserts 1, 11 are similar to the bottom surface 10 of the base metal 2° 12.
, 20, the conventional indexable inserts 1 and 11 are defined to have a certain rake angle and nip angle, and the rake angle and nip angle are set to a certain angle according to the workpiece material or cutting conditions. The angle could not be set, and the characteristics of a composite indexable tip could not be fully utilized.

Furthermore, when cutting mild steel or aluminum alloy, for example, long connected chips are produced, and a groove-shaped chip breaker is often used to break these chips into small pieces.

However, it is difficult to form a chip breaker in the polycrystalline material 4.14 of the above-mentioned composite indexable chip. An indexable chip has been proposed in which the tip is raised at the side edge of a polycrystalline body and the wall thus formed is used as a chip breaker.

However, since the polycrystalline material is expensive, it is formed in small pieces.

For this reason, the distance between the chip breaker and the cutting edge becomes excessively narrow, and there is a risk that chips will become clogged between them.

This point has been helped by the fact that indexable inserts such as those described above are used for high-speed cutting and produce a large amount of chips per unit time.

The present invention was developed in view of the above circumstances, and it is possible to set the rake angle and nip angle that match the workpiece material or cutting conditions without using a special holder, and it also prevents chip clogging. The purpose of this invention is to provide a composite indexable tip that will never cause problems.

Embodiments of the present invention will be described below with reference to FIGS. 5 to 7.

In the indexable tip 21 shown in these figures,
The base metal 22 is formed of steel, cemented carbide, ceramic, or the like into a rectangular flat plate with a trapezoidal cross section, and its overall shape is approximately the same as that of a conventional indexable tip.

At one corner of this base metal 22, there is a seat 2 which is inclined from the apex of the corner toward the bottom surface 27 as it goes inward.
3 is formed, and a polycrystalline body 24 as a cutting edge portion is fixed to this seat 23 via a bottom plate 25 by brazing or the like.

This polycrystalline body 24 is made of a polycrystalline sintered body such as diamond or cubic boron nitride, and is formed into a relatively thin flat plate like the polycrystalline body in the conventional composite indexable tip. It is.

Since the seat 23 is inclined, the rake face 26 of the polycrystalline body 24 has a positive rake angle, and the nigure face 28 coincides with the circumferential side surface 29 of the base metal 22. .

On the other hand, the portion of the upper surface 30 of the base metal 22 that continues to the polycrystalline body 24 is a sloped surface that is continuous with the scoop surface 26 of the polycrystalline body 24, and the rear end of this sloped surface 32, that is, A rising wall portion 31 is formed at a location spaced apart from the polycrystalline body 24 .

Since the indexable tip 21 configured as described above has a base metal 22 that has almost the same overall shape as a conventional indexable tip, it can be attached to a commonly used holder for cutting tools. However, in this case, since the polycrystalline body 24 is inclined with respect to the bottom surface 27 of the base metal 22, the rake angle and the nip angle do not depend only on the chip mounting seat formed on the holder used. A predetermined angle is determined by the inclination angle of the polycrystalline body 24 with respect to the bottom surface 27 of the base metal 22.

Therefore, even if the holder used, especially its chip mounting seat, is a standardized type, if the angle of inclination of the polycrystalline body 24 with respect to the bottom surface 27 is set to an appropriate degree in advance, the rake angle can be adjusted. The angle can be adjusted to match the target workpiece material or cutting conditions, and as a result, the characteristics of the composite indexable insert can be fully utilized during cutting operations.

In addition, in the throw-away tip 21 having the above configuration, a part of the upper surface 30 of the base metal 22 is formed into an inclined surface 32 that is continuous with the scoop 26 of the polycrystalline body 24.
Although a step occurs on the upper surface 30 of the polycrystalline material 24, since this step, that is, the rising wall portion 31 is spaced apart from the polycrystalline body 24 as described above, the resulting cutting flow is not hindered.

8 to 10 show the main parts of another embodiment of the present invention, in which the same parts as in the above embodiment are given the same reference numerals. The mounting angle of the body 24, that is, the rake angle of the polycrystalline body 24 is set larger, and the polycrystalline body 2 of the inclined surface 32 is
A rising wall portion 31 is formed at a location spaced apart from 4.

Even with a throw-away tip configured in this way,
The same effects as the throw-away tip 21 of the above embodiment can be obtained.

In each of the above embodiments, the polycrystalline material 24 is fixed to only one corner of the base metal 22, but the present invention is not limited to the above embodiments, and may have a structure in which the polycrystalline material is fixed to each of a plurality of corners. In addition, when the polycrystalline body 24 is fixed to the seat 23, there is no particular need to interpose the bottom plate 25 as in the above embodiment, and the polycrystalline body may be fixed by direct pressure.

As explained above, according to the present invention, since the polycrystalline body serving as the cutting edge is inclined with respect to the bottom surface of the alloy and is fixed to the corner of the alloy, the indexable insert is attached to the holder. When used as a cutting tool, the rake angle and nip angle can be adjusted to suit the workpiece material or cutting conditions. In addition to forming an inclined surface that is continuous with the polycrystalline body, we formed a rising wall section on this inclined surface at a location away from the polycrystalline body, so even if the polycrystalline body is formed into extremely small pieces, the rising wall section (chip breaker) ) and the cutting edge can be separated by a sufficient distance, and thereby the chips can be separated by the rising wall without causing chip clogging. Therefore, according to the composite indexable insert of the present invention, It is possible to perform good cutting that takes full advantage of the characteristics.

[Brief explanation of drawings]

Fig. 1 is a front view of a conventional composite indexable insert, Fig. 2 is a side view thereof, Fig. 3 is a front view of another conventional composite indexable insert, Fig. 4 is a side view thereof, and Fig. 5 is a front view of the conventional composite indexable insert. FIG. 6 is a front view of one embodiment of the present invention, FIG. 6 is a side view thereof, FIG. The figure is a view taken along the line ■ in FIG. 8, and FIG. 10 is a view taken along the X-ray arrow in FIG. 21... (Composite) Throwaway tip, 22
...Base metal, 24...Polycrystalline body, 26.
...Screw surface, 27...Bottom surface, 30...
...Top surface, 31...Rising wall portion, 32.
・・・・Slope surface.

Claims (1)

[Scope of utility model registration request] In a composite indexable tip in which a flat polycrystalline body is fixed to at least one corner of the alloy as a cutting edge, the polycrystalline body is fixed at an angle with respect to the bottom surface of the base metal, and the polycrystalline body is fixed to the top surface of the base metal. A portion of the polycrystalline body that follows the polycrystalline body is formed as an inclined surface that is continuous with the rake face of the polycrystalline body, and further, a rising wall portion is formed at a portion of this inclined plane that is spaced apart from the polycrystalline body. Composite throw-away tip.