JPH0811008A - Changing type insert with two-stepped breaker projection - Google Patents

Abstract

PURPOSE:To excellently execute the chip treatment even with the small or large depth of cut by slightly erecting a breaker surface, locating another breaker surface higher than a cutting ridge and laying it on the side. CONSTITUTION:Chips are set lower in the small depth of cut, and hit a first breaker surface 3a which is arranged lower than a cutting edge side 4, and this first breaker surface 3a is slightly erected so that the tangential line (x) at the center point may have the inclination of alpha=20-45 deg. relative to the horizontal direction in the perpendicular plane to equally divide a nose part 2, and a large bending stress is applied to the chips, and the chips are curved in a coil spring shape. On the other hand, in the large depth of cut, chips are faced in the horizontal direction or in the slightly upward direction, and hit a second breaker surface 3b located higher than the cutting blade side 4, and this second breaker surface 3b is laid to the side so that the tangential line (y) at the center point may have the inclination beta=10-30 deg. relative to the horizontal direction in the perpendicular plane to equally divide the nose part 2, and the chips are curved in the coil spring shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a replaceable insert used for cutting a material such as metal.

[0002]

2. Description of the Related Art Conventionally, a replaceable insert having a breaker projection formed on a nose portion to bend a chip when cutting a metal material such as a steel material into a spring shape and cut the chip by the bending stress (hereinafter, referred to as (Abbreviated as insert) is used.

[0003] As such a breaker projection insert, one having a simple breaker projection having a substantially hemispherical shape as shown in JP-A-49-32279 is generally used. The substantially hemispherical breaker protrusion can handle both the situation of chips during small cutting that advances as if it sinks after crossing the land and chips during large cutting that advances horizontally or diagonally upward. For example, in the case of small breaker protrusions that do not have such a surface shape, chip processing in small cutting is good, but in chip processing in large cutting, chips cross over breaker projections linearly. If the chip breakage is not good and the breaker protrusion is large, the chips from the small cutting process hit the steep part of the bottom surface of the breaker, which is very large. Cutting resistance is applied to the insert, causing blurring occurs in deficient or working surface of the insert.

Therefore, inserts having breaker protrusions with more complicated surface shapes have been used. As this type of insert 10, an insert having a two-step breaker projection 11 as shown in Japanese Utility Model Laid-Open No. 2-104904 is used. This insert has a projection 11a and a step-up surface 11b as shown in FIGS. Are sequentially formed, the protrusion 11a is higher than the nose tip 12, and the step-up surface 11b formed in parallel along the cutting edge 13 is the nose tip 12.
It was provided with a two-step breaker protrusion 11 formed to be lower.

[0005]

However, even with the conventional two-step breaker projection insert 10 described above, the slope of the step-up surface 11b against which the chips hit during the small cutting process is relatively steep and a large cutting resistance is added to the insert 10. Since the protrusion 11a that causes chipping of the insert 10 and blurring on the machined surface and the chips that hit the chips during the important machining also continues to the top surface that rises steeply, the cutting resistance increases and the corner 11c is chipped. There is a problem that is likely to occur.

Therefore, the insert 10 has a very small chip disposal range.

[0007]

In order to solve the above-mentioned problems, the present invention has a two-step shape having a spherical or elliptical spherical first breaker surface and a second breaker surface on the nose portion of a polygonal insert body. By forming breaker projections, the first breaker surface of the two-step breaker projection is arranged lower than the cutting edge ridge, while the second breaker surface is arranged higher than the cutting edge ridge, so that the chips sink low when making small cuts. Therefore, it hits the first breaker surface which is arranged lower than the cutting edge, and on the other hand, during large cutting, the chips are directed horizontally or slightly obliquely upward so that they hit the second breaker surface.
With the breaker surface standing upright (inclination of the central point tangent of 20 ° to 45 °) so that a large bending stress acts on the chips, the chip is curved in a spiral shape, while the second breaker surface is laid down (center point). The tangential line is tilted at 10 ° to 30 °), and the chip that hits at high speed makes it difficult for the breaker surface to be chipped and the chip to be surely curved in a spiral shape. This provides an insert capable of favorably processing chips in both small and large cuts.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show an insert 1 of this embodiment having a polygonal plate shape. As shown in FIG. 2, the insert 1 has a nose portion 2 having a spherical or elliptical spherical shape.
A two-step breaker protrusion 3 having a breaker surface 3a and a second breaker surface 3b is formed, the first breaker surface 3a being lower than the cutting edge 4 and the second breaker surface 3b being higher than the cutting edge 4. In addition, in the vertical section (the section taken along the line AA) that equally divides the nose portion 2, the central point tangent line x of the first breaker surface 3a of the two-step breaker projection 3 is α = 20 ° to the horizontal direction. The inclination is 45 °, while the tangent line y at the center point of the second breaker surface 3b is β = 10 ° to the horizontal direction
It is configured to have a 30 ° inclination.

Further, as shown in FIGS. 3 to 4, the first breaker surface 3a and the second breaker surface 3b of the two-step breaker protrusion 3 are vertical cross-sections (A-A line) that equally divide the nose portion 2. A vertical cross section (C-C line cross section, which intersects perpendicularly to the cross section)
In the D-D line cross section), the tangent lines x and y at the central points are α = 20 ° to 45 ° and β = 10 ° to 30 with respect to the horizontal direction, respectively.
° It is inclined.

The insert 1 thus constructed has the following features. That is, since the chips sink low when making a small cut, they hit the first breaker surface 3a that is arranged lower than the cutting edge 4, but this first breaker surface 3a
In a vertical cross section (a cross section taken along the line AA) that equally divides the nose portion 2, the central point tangent line x is α = 20 ° to 4 with respect to the horizontal direction.
Since it is made to stand upright with an inclination of 5 °, a large bending stress acts on the chips, causing them to bend in a spiral shape. On the other hand, at the time of large cutting, the chips are directed horizontally or slightly upward, so the second breaker surface 3b positioned higher than the cutting edge 4
In the vertical cross section (cross section A-A line) that equally divides the nose portion 2 on the second breaker surface 3b, the central point tangent line y has an inclination of β = 10 ° to 30 ° with respect to the horizontal direction. As a result, chips that strike at high speed are less likely to cause defects, and the chips are curved in a spiral shape. As a result, chips can be favorably processed in both small cuts and large cuts, and the processing range of chips is dramatically increased.

It should be noted that the inclination α of the central point tangent line x of the first breaker surface 3a with respect to the horizontal direction in a vertical cross section (cross section taken along the line AA) that equally divides the nose portion 2 of the first breaker surface 3a.
(Hereinafter, referred to as the inclination angle α of the first breaker surface 3a) is 2
If it is smaller than 0 °, the bending stress acting on the chips is small and the chips do not bend in a spiral shape. On the other hand, if it is larger than 45 °, the shock of chip collision may cause chipping of the first breaker surface 3a. If the inclination β of the central point tangent line y of the second breaker surface 3b with respect to the horizontal direction (hereinafter referred to as the inclination angle β of the second breaker surface 3b) is less than 10 °, the bending stress acting on the chips is small and the chips are the spring. Not curved in a circle, the other 3
If it is larger than 0 °, the shock of chip collision may cause the first breaker surface 3a to be chipped.

Embodiment 1 In the insert 1 shown in FIGS. 1 to 4, the insert of the present invention in which the inclination angle β of the second breaker surface 3b is 20 ° and the inclination angle α of the first breaker surface 3a is as shown in Table 1. Created 1.

[0013]

[Table 1]

Using these inserts 1, the alloy steel SCM435 was cut for 8 minutes under the following conditions, and the state of the inserts 1 was observed. Table 1 shows the results. V = 250 m / min d = 2 mm f = 0.45 mm / rev Wet processing As is clear from Table 1, when the inclination angle α of the first breaker surface 3a is less than 20 °, the bending stress acting on the chips is small and the chips are small. It was found that the first breaker surface 3a may be chipped due to the shock of chip collision if it is not bent in a spiral shape and is larger than 45 °.

Embodiment 2 In the insert 1 shown in FIGS. 1 to 4, the insert of the present invention in which the inclination angle α of the first breaker surface 3a is 30 ° and the inclination angle β of the second breaker surface 3b is as shown in Table 2. Created 1.

[0016]

[Table 2]

Using these inserts 1, the alloy steel SCM435 was cut under the conditions of Example 1 for 8 minutes, and the state of the inserts 1 was observed. Table 1 shows the results. As is clear from Table 2, the inclination angle β of the second breaker surface 3b is 1
It has been found that if the angle is smaller than 0 °, the bending stress acting on the chips is small and the chips do not curve in a spring shape, whereas if the angle is larger than 30 °, the first breaker surface 3a may be chipped due to the shock of chip collision.

[0018]

According to the insert of the present invention, the nose portion of the polygonal insert body is formed with a two-step breaker protrusion having a spherical or elliptical spherical first breaker surface and a second breaker surface. 1 With the breaker surface standing upright (inclination of the central point tangent 20 ° to 45 °), a large bending stress acts on the chips so that the sinking chips at the time of small cutting are curved in a spiral shape. Place the second breaker surface higher than the cutting edge and lay it down (center point tangent line 10
The inclination of ° ~ 30 °) at a high speed at the time of large cutting, the chip that hits horizontally or slightly diagonally upward does not chip the breaker surface and the chip is curved in a spiral shape. Good chip control can be performed in both cuts and large cuts.

[Brief description of drawings]

FIG. 1 is a plan view of a replaceable insert with a two-step breaker protrusion according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a sectional view taken along line CC of FIG.

FIG. 4 is a sectional view taken along the line DD of FIG.

FIG. 5 is a plan view of a conventional replaceable insert with a two-step breaker protrusion.

6 is a cross-sectional view taken along the line EE of FIG.

[Explanation of symbols]

 1 (Exchangeable) Insert 2 Nose Part 3a First Breaker Surface 3b Second Breaker Surface 3 Breaker Projection 4 Cutting Edge x, y Center Point Tangent α, β Inclination Angle

Claims (1)

[Claims] 1. An insert, wherein a nose portion of a polygonal insert body is formed with a two-step breaker protrusion having a spherical or elliptical spherical first breaker surface and a second breaker surface, wherein The breaker surface is arranged lower than the cutting edge, while the second breaker surface is arranged higher than the cutting edge, and in the vertical cross section that equally divides the nose portion, the center point tangent line of the first breaker surface of the two-step projection is arranged. Has an inclination of α = 20 ° to 45 ° with respect to the horizontal direction, while the central point tangent line of the second breaker surface has an inclination of β = 10 ° to 30 ° with respect to the horizontal direction. Interchangeable projection insert.