JPS591105A - Throwaway tip - Google Patents

Abstract

PURPOSE:To reduce cutting resistance and prevent the smoothness of a machined surface from falling, by straightening the cutting edges of a throwaway tip seeing perpendicularly to both its sides and by providing protrusions and recesses on at least the rising surface of a chip breaker along the cutting edges. CONSTITUTION:A chip breaker 34 is provided with protrusions and recesses as waves along cutting edges 31 at all sides of the chip breaker. As a result, the area of contact of the chip and the breaker 34, particularly of the chip and the rising surface of the breaker, is reduced so that cutting resistance is diminished. Since the cutting edges 31 have straight portions 31a as seen perpendicularly to both the sides, a machine surface is not formed with a projection and a recess. The machine surface is thus prevented from deteriorating.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an indexable insert in which a chip breaker groove is formed along a cutting edge.

In general, many indexable inserts have a chip breaker groove formed along the cutting edge to forcibly curl and break off chips to improve their processing performance. As this type of slow-aqua chips, the ones shown in FIGS. 1 to 3 or 5 to 7, for example, are conventionally known.

The indexable tip l shown in FIGS. 1 to 3 is
A chip deflection force 1112 having a uniform cross section and a descending surface 12a and a rising direction 12b is formed along the cutting edge ti. When cutting is performed using such an indexable insert l, as shown in Fig. 4,
The chips T generated by the cutting blade 11 and extending along the descending surface 12a are forcibly curled by coming into contact with the rising surface 12b, thereby making it possible to break the chips T into small pieces.

However, in such an indexable insert l, the chip breaker @12 has a uniform cross section, and the cutting edge 1
1, the entire width of the chip T comes into contact with the rising surface 12b of the chip breaker s12 at the same time, which increases the cutting resistance and ultimately reduces the life of the indexable chip 1. Moreover, there were problems such as the need to lower the conditions for turning off the gas. .

On the other hand, the indexable insert 2 shown in FIGS. 5 to 7 has a chip breaker groove 22 along the cutting edge 21 in which the severity and width of the chip breaker groove 22 change in a wavy manner toward the direction in which it extends. At the same time, a groove portion 238 is formed in a portion of the chip top surface (chip bottom surface) 23 corresponding to the deepest part of the chip breaker groove 22 to change the level difference CI at each location between the chip top surface 23 and the chip breaker groove 22. This reduces the contact area of chips with the chip breaker groove 22, thereby reducing cutting resistance.

However, in this indexable insert 2, the depth of the chip breaker groove 22 is changed in a wavy manner, and the side view shape of the cutting edge 21 is made wavy, as shown in FIG. If a clearance angle α is given to the chip side surface 24, a difference of % will occur in the cutting depth of each part of the cutting edge 21 into the workpiece W. For this reason, for example, when chamfering is performed using the straight portion 21a of the cutting blade 210, there is a problem in that unevenness occurs on the cut surface, which worsens the cut surface by n degrees.

This invention was made in order to solve the above-mentioned problems, and an object of the present invention is to provide an indexable insert that can reduce cutting resistance and prevent deterioration of illuminance on the cutting surface. do.

The feature of this invention is that while the side view shape of the cutting blade is linear, at least the main upright iNi of the chip breaker groove is formed with an uneven surface portion having an uneven cross-sectional shape 27i on the cutting blade. It's on point nine.

Hereinafter, one embodiment of the present invention will be explained with reference to FIGS. 9 to 15.
Explain by referring to the diagram. FIG. 9 is a front view of the indexable tip according to the present invention, and FIG. 1O is a side view thereof from below. Note that the triangular throw-away tip 3 shown in these figures has the same configuration on both upper and lower end surfaces, so only the upper end surface will be explained below, and the lower end surface will be explained with the same structure as the upper end surface. The same reference numerals are given, and the explanation thereof will be omitted.

A cutting edge 31 is formed on the periphery of the upper end surface of the throw 7-way tip 3. The cutting edge 31 is composed of a straight portion 31a and a nose portion 31b, and has a straight shape when viewed from the side. Further, a chip upper surface 32 that protrudes slightly upward from the cutting edge 31 is formed at the center of the same end surface. Between the upper surface 32 of the chip and the cutting edge 31, a narrow land portion 33, a chip breaker groove 34, and a groove 34 are formed in order from the cutting edge 31 side to the top rfjI32 side of the chip.
It is formed along 1.

The # side of this chip breaker groove 34 has an I4'F surface 34a that slopes downward from the land 33 toward the groove bottom, and a rising surface 34b that rises from the groove bottom toward the chip top surface 32.
It has Then, on the groove surface of such a chip breaker groove 34, a plurality of four parts 35 are formed so as to be smoothly continuous with each other's closest parts 9 in the direction of the chip breaker groove 34. . These recesses 35 are all of the same shape and size, and are constructed along a part of an imaginary inverted body with the pitcher direction facing the cutting blade 31.

Therefore, as shown in FIGS. 11 to 14, the recess 3
5 has a depth that gradually becomes shallower as it goes from the center toward the chip breaker groove 34, and in the continuous part of the chip breaker groove 34,
It is designed to match the groove surface of No. 4. Moreover, do these recesses 35 touch the land portion 33 at one end in the pitcher direction? The chip breaker s34 extends from the other end or rising portion 34b to the chip upper surface 32, and therefore, as shown in FIG. It has a roughly wavy shape. Note that by forming such a recess 35, the rising surface 3 of the chip breaker groove 34
The joint portion between the chip 4b and the top surface 32 of the chip also has a wavy shape.

However, when cutting is performed using such an indexable insert 3, since the cross-sectional shape of the groove surface of the chip breaker groove 34 along the cutting edge 31 is # or approximately wavy, chips and chips are separated. The cutting resistance can be reduced by reducing the contact area with the breaker groove 34, especially the contact area with the upright surface 34b. In addition, since the straight portion 31a has a straight shape in side view, when cutting is performed using the straight portion 31a, there will be no unevenness on the cut surface of the workpiece, thereby preventing deterioration of the cut surface. I can do it.

Figure 16 shows another embodiment of this invention.
In this throw-away tip 3, the nose portion 31
A protrusion 36 is provided at the joint between the four adjacent parts 35 in b.
was formed. The protrusion 36 may be formed at a location other than the recess 35 of the chip breaker groove 34, or may be formed so as to be continuous with the chip upper surface 32. Note that the other configurations are the same as those of the above embodiment, so the same reference numerals are given to the same ladder parts and the explanation thereof will be omitted.

In this way, the chip disposal range can be expanded for use with low depth of cut and low feed.

In addition, in the above embodiment, the throw-away tip 3
The upper and lower ends of the ρ 5, the chip breaker $34, the four parts 35, etc., which have the same configuration on both the upper and lower end faces, may be configured differently on the upper and lower end faces. Further, the cutting edge may be formed only on one end surface of the indexable tip.

In the above embodiment, the recesses 35 have the same shape and size; however, they may have different shapes and sizes.

Further, in this case, the recess 35 on the nose portion 31b side is replaced by the straight portion 3.
The width of the chip breaker @34 is increased from the nose part 3113 side to the center part of the straight part 31a while making the joint part between the chip breaker groove 34 and the chip top surface 32 into a wavy shape. It may also be made to gradually become larger as it approaches . Note that, of course, this may be reversed.

Furthermore, in the embodiment described above, by forming the recessed portion 35, the cross-sectional shape along the cutting edge of the chip breaker s34 is made wave-like. The location where the broken four parts 35 or the convex parts are formed is the rising face 34, since the main cause of the increase in cutting resistance is the still contact between the chips and the rising face 34b.
It may be only a part of the rising surface 34b, or only a part of the rising surface 34b. Note that the cross-sectional shape of the chip breaker groove 34 along the cutting edge may be a simple uneven shape.
4. 1 good.

Furthermore, the shape of the indexable tip is not limited to a triangular shape, but may be a regular polygon, a rhombus, a parallelogram, or a round, and may be either a negative tip or a positive tip. Note that the land portion 33 may not be formed.

As explained above, according to the indexable insert of the present invention, the cutting edge has a linear shape in side view, while at least the rising surface of the chip breaker groove has a cross-sectional shape along the cutting edge or an uneven shape. Since the uneven surface portion is formed, it is possible to reduce the contact area of chips with the chip breaker groove surface, thereby reducing cutting resistance, and furthermore, it is possible to prevent deterioration of the cut surface. In addition, by reducing the cutting resistance, cutting conditions can be raised to improve production efficiency υN
Effects such as being able to improve lives can be obtained.

[Brief explanation of the drawing]

Figures 1 to 3 show an example of a conventional indexable insert, with Figure 1 being a front view, Figure 2 being a side view from below, and Figure 3 being the II+-■ Junya of Figure 1. 4 is a diagram showing the cutting process using the indexable insert shown in FIGS. 1 to 3, and FIGS. 5 to 7 show other examples of the conventional indexable insert, and FIG. is a front view of the same, Fig. 6 is a side view from below, Fig. 7 is a cross-sectional view of the I-Vll line in Fig. 5, and Fig. 8 is based on the indexable tip shown in Figs. 5 to 7. 9 to 15 show an embodiment of the present invention, FIG. 9 is a front view thereof, FIG. 1O is a 111j side view from below, and FIGS. The figures are respectively shown in Figure 9 (7))l-XL'All-X1[,X1ll
-X (II.
A cross-sectional view along the V-xV line, FIG.
・Throwaway tip, 31・・Cutting blade, 34・・
・Chip breaker groove, 34b・・Rising surface, 35・・
・Concavity. Applicant Mitsubishi Metals Co., Ltd. Agent Patent Attorney Masatake Shiga "'1 Figure 15 3 Figure 16

Claims (1)

[Claims] In an indexable insert in which a chip breaker groove is formed on the peripheral edge and along a cutting edge, the cutting edge is linear in side view, and the cutting edge is formed at least inward from the cutting edge side of the chip breaker groove. 2. A throw-away tip, characterized in that a surface that gradually rises toward the cutting edge is formed with an uneven surface portion having a cross-sectional shape along the cutting edge or an uneven shape.