JPH04115808A - Throw-away chip - Google Patents

Abstract

PURPOSE:To effectively discharge produced chips without being blocked, by changing the inclination angles of first and second inclined faces which are turned into a negative condition from a positive position in the nose section, moderately in a direction away from the nose section. CONSTITUTION:A nose section 14 is formed therein with a positively inclined surface 16 having a positive inclination angle theta of 5 to 16 deg., a first negatively inclined surface 17a, continuous to the former, having a negative inclination angle 4theta1 of about 36 to 44 deg. and a second negatively inclined surface 17b having a negative inclination angle theta11 of about 45 to 55 deg., these inclined surfaces 17a, 17b being continuous through the intermediary of a flat surface 17. The inclined angles theta1, theta11 are moderately changed in a direction away from the nose section 4. Thread-like chips produced from the cutting edge of the nose section pass over under abrasion, at first, the positively inclined surface, and then impinge upon the first inclined surface so as to be fragmented. Further, they pass over the flat surface under abrasion and impinge upon the second inclined surface so as to be finely fragmented.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to an indexable insert for cutting metals, etc. More specifically, it relates to an indexable insert for cutting metal, etc., and more specifically, it This invention relates to a grooved indexable insert that can effectively dispose of chips when the cutting situation changes to end face cutting.

[Prior art] Conventionally, in tips for cutting metal, etc., grooves have been formed around the entire circumference of the tip or at desired positions in order to finely crush the chips generated during cutting to improve workability and safety. is used.

It has also been proposed that small protrusions or depressions are provided in the nose portion of the groove so that filamentous chips generated during minute cuts are crushed by colliding with the small protrusions or depressions or by passing the car through them. has been done.

[Problems to be Solved by the Invention] However, when cutting with a chip with small protrusions or depressions formed near the nose of the chip, when cutting with a small depth of cut at low rotation and low feed, the cutting edge of the nose part The thread-like chips that are generated are relatively quiet and successfully reach the small protrusions and depressions near the nozzle and are broken up, but if this is a minute cut and the cutting is performed at high speed and high feed rate, the chips will jump around. Since the chips are generated in such a state, the chips do not reach the small protrusions and depressions mentioned above, resulting in long thread-like chips that have extremely poor workability and safety.

In addition, when the cutting condition changes from peripheral cutting, in which cutting is mainly performed by the nose of the chip, to end face cutting, which is performed by the nose and the straight cutting edge, small protrusions or depressions may be created in the grooves or areas described above. Otherwise, the chips may become clogged, resulting in damage to the cutting edge or damage to the rigid material.

[Purpose of the Invention] The present invention was made to solve the above-mentioned problems, and it is possible to improve workability and safety by finely crushing chips generated during cutting even when performing high-speed rotation back cutting with a minute depth of cut. The objective is to provide an indexable insert with extremely good cutting efficiency that can effectively discharge generated chips without clogging even when the cutting condition changes from peripheral cutting to end face cutting. be.

[Means for Solving the Problems] The present invention solves the aforementioned problems by the means described below.

In other words, the flank and rake surfaces of a plate-shaped, polygonal chip form a cutting edge, and the rear side of this cutting blade has a positive edge that continues to the flat surface provided at the center of the chip. A slope and a negative slope are provided, and furthermore, at the nose portion, a first slope and a second slope, which are negative following the positive slope, have a flat surface and are continuous with the flat surface, This is a throw-away tip in which the inclination angles of the first slope and the second slope, which are negative, gradually change as they move away from the nozzle portion.

[Operation of the Invention] Since the present invention is configured as described above, in the case of high-speed rotation and high-feed cutting with a minute depth of cut, curled thread-like chips generated from the cutting edge of the nose portion are First, the vehicle is passed through a positive slope, then it is crushed or extremely easily crushed by colliding with a negative first slope, and then it is crushed into fine pieces by being rubbed on a flat surface and colliding with a negative second slope. .

In addition, since the rake face continuous with the cutting edge has a positive slope, the cutting resistance is greatly reduced and machinability is significantly improved. Therefore, gentle chips can be generated by high-speed rotation and high-feed cutting at minute depths of cut. The above-mentioned action can be performed extremely smoothly by preventing chips from flying around.

In addition, since the inclination angles of the negative first slope and the second slope were gradually changed in the direction away from the nose part, the cutting situation changed from peripheral cutting to end face cutting, that is, from the cutting edge at the nose part to the straight cutting edge. Even when cutting, it is possible to generate chips that are easily discharged, allowing good cutting to be performed without causing chip clogging.

[Embodiment] The present invention will be described in detail below with reference to the attached drawings.

The figures show an indexable tip according to the present invention, in which Figure 1 is a front view, Figure 2 is a side view of Figure 1, and Figure 3 is a side view of Figure 1.
FIG. 4 is a cross-sectional view of FIG. 3, and FIG.
Figure (b) is a sectional view taken along line B-B in Figure 3, and Figure 4 (C) is a cross-sectional view of the third
4(d) is a sectional view taken along line DD in FIG. 3, and FIG. 4(e) is a sectional view taken along line EE in FIG. 3.

A plate-shaped, triangular tip 1 has a cutting edge 13 consisting of a flank face 11 and a rake face 12, and a nose part 14 provided at a predetermined radius is formed at a part of the corner. A mounting hole 10 is provided in the center, and the center portion including the mounting hole 10 has a height W higher than the round cutting edge 13.
There is a flat surface 15 at .

Continuing with the cutting edge 13, the nose portion (A-A cross section in Fig. 3) has an inclination angle θ of 5° to 16° (preferably 8° to 8°).
A positive slope 16 with an inclination angle θl of 36° to 44° (preferably 38° to 42°, 40° in the example) follows this slope 16. A negative second slope 17b is provided with an inclination angle θ1□ of 45° to 55° (preferably 47° to 53°, 50° in the embodiment).
It has a plane 17 and is continuous with the slope 17b.

Further, at the starting point of the linear cutting edge 13a (cross section B-B in FIG. 3), a positive slope 16 having the same inclination angle θ as described above and a negative first slope 17a form a flat surface 17. It is continuous.

The point where the chip is sectioned along C-C is the straight cutting edge 1.
Continuing from 3a, there is a positive slope 16 having the above-mentioned inclination angle θ, followed by a slope 16 of 26° to 35″ (preferably 28° to 33°).
, in the example is 30°) Negative slope 17 having an inclination angle θ11□
C is formed, and the section of the chip taken along the line DD has a positive slope 16 having the above-mentioned inclination angle θ and a slope of 16° to 29°.
° (preferably 18° to 28°, 25° in the embodiment) and a negative slope 17e having an inclination angle θ', and the E-E cross section at the center of the chip is the above-mentioned D-D cross section. are formed with approximately the same inclination angle, and each positive slope 1
The length of 6 is the shortest at the B-B section (11) <, D-D
The negative slope 17e is formed to be longest at the cross-sectional point (1') and has a wavy shape, and the inclination angles θ1, θ11, θ1 of the negative first slope 17a and the negative second slope 17b are
, □ gradually change its angle as it moves away from the nose portion 14.

Note that this angle may be changed gradually in a polygonal line with a certain angle as it moves away from the nose part, or it may be changed gently in a curved line from the center of the nose part. good.

Furthermore, although the embodiment has been described with respect to a triangular chip, this can also be used for a polygonal chip such as a quadrangle, a rectangle, or a rhombus.

[Effects of the Invention] Fix the tip of the present invention to a bite shank, attach it to a machine tool, and test it.

The test conditions at that time were: Work material: 5Cr420H1 Cutting speed: 200 m/min, Feed: 0.3 mm/rev,
Depth of cut: 0°5mm (outer circumference cutting).

The results of the above tests indicate that finely crushed chips with high processability were generated in peripheral cutting.

In addition, when transitioning from peripheral cutting to end face cutting, the cutting edge of the insert was 4.72 mm, but the chips generated at this time were also curled and easily discharged, and the cutting edge caused by chip clogging was There was no breakage or damage to the rigid material.

[BRIEF DESCRIPTION OF THE DRAWINGS] The figures show an indexable tip according to the present invention, in which FIG. 1 is a front view, FIG. 2 is a side view of FIG.
FIG. 4 is a cross-sectional view of FIG. 3, and FIG.
Figure (b) is a sectional view taken along line B-B in Figure 3, and Figure 4 (c) is a cross-sectional view of Figure 3.
4(d) is a sectional view taken along line DD in FIG. 3, and FIG. 4(e) is a sectional view taken along line EE in FIG. 3. 1---Throwaway tip 11-11 flank 1
2---Rake face 13・13a---All blades 14-m
-Nose 15-m-Flat surface 16--Slope 17a
-m-first slope 17b--second slope 17cm-- slope diagram [61 (b)] and σ (d)

Claims (1)

[Claims] (1) A tip for cutting metal, etc., which is plate-shaped and polygonal, and has a cutting edge composed of a flank face and a rake face, and a cutting edge is provided at the center of the tip on the rear side of the cutting edge. A positive slope and a negative slope are provided which are continuous to the flat surface, and furthermore, at the nose part, following the positive slope, a negative first slope and a negative second slope are provided. 1. A throw-away tip characterized in that the first negative slope and the second negative slope are continuous with the surface, and the inclination angles of the negative first slope and the negative second slope gradually change as they move away from the nose part.