JPH10128604A - Cutting insert - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely curl chips in cutting and break the same at a suitable length to be stably discharged by making the wavy cutting edge and the upper end part of a wave surface part flat, and forming plural edges intersecting perpendicularly to the cutting edge on the wave surface part. SOLUTION: As a part of a cutting edge 3 is wavy, chips are easy to be bent and wavy in the cross direction at this part, and further a wave surface part 9 is formed in a breaker groove 6 along the wavy cutting edge 3, and the upper end part is made flat, whereby as plural edges 9a intersecting perpendicularly to the cutting edge 3 are provided on the wave surface part 6, the chips are parted to be narrower by the edges 9a. The narrow chips which are bent in the cross direction are brought into contact with a breaker projection 8 to be very easily curled and broken at a suitable length. The narrow chips which are bent in the cross direction are made stable in the discharge direction so as to be handled favorably.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting insert used for cutting metal materials and the like, and particularly suitable for cutting difficult-to-cut materials.

[0002]

2. Description of the Related Art Conventionally, an insert having a shape as shown in FIG. 5 has been proposed. That is, concave and convex portions are formed on three sides of a triangular insert main body 21 in which a screw hole 2H for fixing to a holder (not shown) is formed at the center, in a plan view from the rake face side, in which a straight line is continuous at right angles. There has been provided a cutting insert with a cutting edge 24 consisting of a section.

[0003] Such an uneven cutting blade 24 is configured to break chips finely for a material which is difficult to process chips.

That is, since the chips are cut at the right-angled corners of the projections and become narrow, the chips can be easily curled by contacting breaker projections (not shown), and as a result, the chips are cut into appropriate lengths. In this way, the chips are prevented from being entangled with the holder or the like and causing no harm to the operator.

[0005] As a cutting insert having such an uneven cutting blade, there is a cutting insert in which the cutting blade is formed in a saw blade shape.
This configuration is intended to increase the length of the cutting edge per unit cutting width and sufficiently reduce the stress generated on the entire cutting edge due to resistance during cutting.

[0006]

However, the above prior art has the following problems. That is, as described above, when the cutting edge has a linear uneven shape in plan view from the rake face side,
There is a problem that the strength of the protruding portion is small, and particularly the acute or right-angled corners are easily lost.

[0007] Therefore, even if the cutting force per unit cutting width is reduced by making the shape of a saw blade, the problem that these parts are easily damaged cannot be avoided.

[0008]

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, the present invention relates to a cutting insert particularly suitable for cutting the outer periphery of a shaft made of a difficult-to-cut material such as an iron plate material. By cutting at a long length, it stably discharges and excels in chip disposal capacity, without reducing the cutting edge strength of the cutting edge and reducing cutting resistance,
It is an object of the present invention to provide an efficient and economical cutting insert having a good finish and a long tool life.

[0009]

In order to solve the above-mentioned problems of the prior art, a cutting insert according to the present invention has a breaker projection formed at a central portion in a breaker groove of a nose portion, and further has cutting edges on both sides of the breaker projection. Is formed in a wavy shape in a side view, and a wavefront portion is provided along the wavy cutting edge in the breaker groove, and the upper ends of the wavy cutting edge and the wavefront portion are flattened to form the wave. A plurality of edges perpendicular to the cutting edge are formed on the surface.

[0010]

According to the cutting insert of the present invention, a part of the cutting blade is formed in a wave shape in a side view so as to surely curl the chips generated by the cutting and to stably discharge the chips by cutting the chips at an appropriate length. A wavefront portion was provided along the wavy cutting edge in the breaker groove, and a plurality of edges orthogonal to the cutting edge were formed in the convex portion by flattening the upper end portion of the wavy cutting edge and the wavefront portion. Things.

That is, a part of the cutting edge is formed in a wavy shape when viewed from the side (plan view from the flank), is formed without irregularities when viewed from the rake face side, and is mainly curved and has a stress direction. And the edge portion is not an acute angle or a right-angled corner, so that the strength of the cutting edge is hardly reduced.

Further, since a part of the cutting edge is corrugated, the chip is likely to be curved in the width direction at this portion, and further, a corrugated surface is formed in the breaker groove along the corrugated cutting edge, In addition, by making the upper end portion a flat surface, a plurality of edges orthogonal to the cutting edge are provided in the wavefront portion, so that the chips are finely divided by the edge. Then, the chips that are narrow and curved in the width direction are extremely easily curled on the breaker projections, and as a result, are cut into appropriate lengths. In addition, the chips that are narrow and curved in the width direction as described above are stable in the discharge direction, and are thus satisfactorily processed.

It is preferable that the above-mentioned wavy cutting edge and the wavy surface along the cutting edge are not formed near the tip of the nose of the cutting insert. This is because when these are formed at the tip of the nose, the tip of the nose which is most susceptible to impact during cutting has insufficient strength and may be broken.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIGS. 1 to 3 show a cutting insert 10 according to the present embodiment, and the overall shape of the cutting insert 10 is a rhombus shape in which the cutting edge angle of the nose portion 4 is small, and a portion between the rake face 1 and the flank 2 is provided. The cutting edge 3 is formed on the ridge.

The nose portion 4 has a breaker groove 6 connected to the cutting edge 5 and a breaker projection 8 connected to the seating surface 7 at a central portion of the breaker groove 6.

As shown in the side view of FIG. 2, the cutting insert 10 has a part of the cutting blade 3 for surely curling chips generated by the cutting and stably discharging the chips by cutting the chips at an appropriate length. Is formed in a wavy shape in a side view, and a wavefront portion 9 is provided along the wavy cutting edge in the breaker groove 6 as shown in the enlarged view of FIG. 3 and the cross-sectional view of FIG. The cutting edge 3 and a plurality of edges 9 orthogonal to the cutting edge 3 are formed on the wavefront 9 by flattening the upper end portions of the wavefront 9.
a part of the cutting blade 3 is formed in a wavy shape in a side view (plan view from a flank), is formed without irregularities when viewed from the rake face 1 side, and has a mainly curved shape. In addition, the stress direction is dispersed, and the edge portion is not an acute angle or a right angle corner, so that the strength of the cutting edge of the cutting edge 3 is hardly reduced.

Further, since a part of the cutting edge 3 is wavy, the chip tends to be curved in the width direction at this part.
A plurality of edges 9a orthogonal to the cutting edge 3 are provided in the wavefront portion 9 by forming a wave surface portion 9 in the breaker groove 6 along the wavy cutting edge 3 and flattening the upper end portion thereof. Therefore, the chips are finely divided by the edge 9a. Then, the chips that are narrow and curved in the width direction are extremely easily curled on the breaker projections, and as a result, are cut into appropriate lengths. In addition, the chips that are narrow and curved in the width direction as described above are stable in the discharge direction, and are thus satisfactorily processed.

The width w of the flat surface 9b of the wavefront portion 9
If (see FIG. 3) is less than 0.3 mm, the chips may not be divided into small pieces and may be formed in a wavy shape, and the processing of the chips may not be performed sufficiently satisfactorily. Even in the case of a large chip, there is a possibility that the chips are similarly not divided finely and are formed in a wavy shape, and the processing of the chips is not sufficiently performed.

If the height difference g (see FIG. 2) of the cutting edge at the wavy portion of the cutting edge 3 is less than 0.05 mm, the chips are not divided into small pieces, are formed in a wavy shape, and the processing of the chips is sufficient. There is a possibility that the cutting is not performed satisfactorily, and if it is larger than 0.2 mm, the strength of the cutting edge portion of the cutting blade 3 is insufficient and there is a possibility that the cutting edge 3 may be broken.

The present invention is not limited to the above-described embodiment, but can be in any form without departing from the object of the invention.

[0021]

EXAMPLE 1 In the cutting insert 10 shown in FIGS.
The width w of the flat surface 9b of the wavefront portion 9 is 0.6 mm, and the height g of the cutting edge at the wavy portion of the cutting edge 3 is 0.14.
mm, a processing test was performed under the following cutting conditions, and the results were visually evaluated.

Cutting conditions V = 150 m / min d = 1 to 4 mm (variable) f = 0.3 mm / rev Work material: FC25 sleeve material Tool shape: DNMG150412 Cutting fluid: Yes On the other hand, as a comparative example, a wave front portion A machining test similar to that described above was performed using a cutting insert having the same shape as that of the above-described example product except that the flat surface 9b was not provided on 9.

[0023] As a result, while the above-mentioned example product had good chip treatment, the comparative example product had a tendency for chips to be discharged while being extended.

Embodiment 2 In the cutting insert 10 shown in FIGS.
A cutting insert 10 having a height difference g of the cutting edge 3 of 0.14 mm and a width w of the flat surface 9b as shown in Table 1 was prepared, and a processing test was performed under the same cutting conditions as in Example 1. And the results were observed with the naked eye. Table 1 shows the results.

[0025]

[Table 1]

From the above results, it was found that the width w of the flat surface 9b is preferably in the range of 0.3 to 1.0 mm.

Embodiment 3 In the cutting insert 10 shown in FIGS.
A cutting insert 10 having a height difference g of the cutting edge 3 as shown in Table 1 and a width w of the flat surface 9b of 0.6 mm was prepared, and a machining test was performed under the same cutting conditions as in Example 1. And the results were observed with the naked eye. Table 2 shows the results.

[0028]

[Table 2]

From the above results, it was found that the height difference g of the flat surface 9b was preferably in the range of 0.05 to 0.3 mm.

[0030]

As described above, in the cutting insert of the present invention, a breaker projection is formed at a central portion in the breaker groove of the nose portion, and a part of the cutting edge is formed in a wavy shape in a side view. A wavefront portion is provided along the wavy cutting edge in the breaker groove, and a plurality of edges orthogonal to the cutting edge are formed on the wavefront portion by flattening the upper ends of the wavy cutting edge and the wavefront portion. Due to the formation, the chips generated by cutting are surely curled, and are cut at an appropriate length to stably discharge and excel in chip processing performance, while maintaining the cutting edge strength of the cutting edge and reducing cutting resistance. In addition, it has excellent effects such as good finish, long tool life, efficiency and economy.

[Brief description of the drawings]

FIG. 1 is a top view of a cutting insert of the present invention.

FIG. 2 is a side view of the cutting insert of FIG. 1;

FIG. 3 is an enlarged view of a region A in FIG. 1;

FIG. 4 is a sectional view taken along line XX of FIG. 3;

FIG. 5 is a plan view of a conventional cutting insert.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Cutting insert 1 Rake surface 2 Flank 3 Cutting edge 4 Nose part 5 Cutting edge 6 Breaker groove 7 Seating surface 8 Breaker projection 9 Wave surface part 9a Edge 9b Flat surface g Height difference w Width

Claims (1)

[Claims] 1. A cutting insert having a cutting edge formed at a ridge between a rake face and a flank and a breaker projection formed at a central portion of a nose portion in a breaker groove. A part of the blade is formed in a wavy shape in a side view, and a wavefront portion is provided along the wavy cutting edge in the breaker groove, and the upper end portion of the wavy cutting edge and the wavefront portion is flattened. A cutting insert with multiple edges perpendicular to the cutting edge formed on the wavefront.