JP3577981B2 - Indexable tip - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a throw-away chip having a breaker wall in a breaker groove formed on an upper surface.
[0002]
[Prior art]
Conventionally, as this type of throw-away chip (hereinafter abbreviated as chip), as shown in FIGS. 13 to 16, a breaker groove 2 is formed on an upper surface 1 of a rhombic plate-shaped chip. 2, a first breaker wall 5 standing upright in a true spherical shape from the corner 3 toward the center 4, and a second breaker wall 6 formed from the rear toward the center 4. Are known.
[0003]
[Problems to be solved by the invention]
However, in the chip having such a configuration, the first breaker wall 5 has a true spherical shape, in other words, as shown in FIGS. 14 and 15, the radius of curvature R1 along the bisector L of the corner portion 3 is equal to the radius of curvature R1. Since the relationship between the radius of curvature R2 along the direction perpendicular to the branch line L is R1 = R2, there are the following defects.
That is, if the chips are to be surely cut under the cutting conditions of low cutting depth, the first breaker wall 5 must be brought close to the corner portion 3, and under the cutting conditions of high cutting depth, the chips are scattered due to chip clogging. And an increase in cutting resistance.
[0004]
Conversely, in order to prevent chip clogging and an increase in cutting resistance under high cutting conditions, the first breaker wall 5 must be separated from the corner 3 toward the center 4. Under cutting conditions with low cutting depth, the chip breaking performance is reduced.
Therefore, the range of cutting conditions that can be used with one insert has been narrow.
In addition, there is a problem that the discharge of the chips is unstable because the thin plate-shaped chips come into point contact when they come into contact with the breaker.
[0005]
Further, the central portion 4 of the second breaker wall 6 is recessed toward the bisector L side of the corner portion 3 (see FIG. 13) in order to improve the chip dischargeability, so that the breaker groove 2 is widely secured. (See FIG. 16), chips are curled at the bottom of the breaker groove 2 and flow randomly, making it impossible to control the discharge direction.
In addition, the chips not only curl on the bottom surface of the breaker groove 2 but also get over the second breaker wall 6, so that the braking effect is weak.
[0006]
The present invention has been made in view of the above circumstances, and it is possible to reliably control the direction in which chips are discharged, and to realize a chip that can exhibit excellent chip disposability under a wide range of cutting conditions from low cutting to high cutting. For the purpose of providing.
[0007]
[Means for Solving the Problems]
The present invention has the following features to attain the object mentioned above.
That is, the chip of the present invention has a polygonal plate shape, a cutting edge is formed at the intersection ridge portion between the upper surface and the side surface, and a chip having a breaker groove between a corner portion and a central portion of the upper surface,
In the breaker groove, a curved first breaker wall disposed close to the corner portion side,
The first breaker wall is formed such that a radius of curvature R1 along the bisector of the corner portion and a radius of curvature R2 along a direction intersecting the bisector satisfy R1> R2. With
A second breaker wall disposed closer to the central portion than the first breaker wall,
The second breaker wall has a parallel wall extending parallel to the cutting blade .
[0008]
In this configuration, even if the distance from the tip of the corner portion to the first breaker wall is shortened, it is possible to avoid chip clogging at a high cutting depth and an increase in cutting resistance due to an excessively strong braking effect. The distance from the tip to the first breaker wall can be set short, so that chips can be reliably separated at low cutting depth.
[0009]
In addition, by setting the radius of curvature R2 smaller than R1, the distance from the cutting edge to the first breaker wall can be optimized not only at the time of low cutting but also at the time of high cutting.
For this reason, even at the time of high cutting, chip clogging does not occur, cutting resistance is prevented from increasing, and the direction in which chips are discharged can be reliably controlled.
[0010]
The tip of the present invention further includes a second breaker wall disposed closer to the central portion than the first breaker wall, and the second breaker wall includes a parallel wall extending parallel to the cutting blade. I have.
[0011]
In this configuration, the breaker groove formed between the parallel wall and the cutting blade is not excessively widened, and the parallel wall serves to guide the chip discharging direction.
Further, at the time of high cutting, the chips are curled by the parallel wall and are surely cut.
[0012]
Further, in the chip having the above configuration ,
A third breaker wall disposed between the pair of second breaker walls , disposed on the bisector side of the second breaker wall ,
The third breaker wall, the extending to gradually away from the cutting edge, and be formed to be higher than the first and second breaker wall as it goes from the corner portion side to the central portion Is also good.
[0013]
In this configuration, a two-stage breaker is formed by the first breaker wall and the third breaker wall, and by the second breaker wall and the third breaker wall.
For this reason, even if the chips surmount the first breaker wall or the second breaker wall, the chips are curled and separated by the third breaker wall higher than these breaker walls.
[0014]
Further, since the height of the second breaker wall can be reduced by forming the two-stage breaker, it is possible to effectively prevent an increase in cutting resistance due to the second breaker wall.
Furthermore, since the third breaker wall extends inclining toward the bisector of the corner portion rather than in a direction parallel to the cutting edge, it is possible to effectively prevent an increase in cutting resistance due to the third breaker wall at high cutting depth.
Still further, in the chip having the above configuration, the second breaker wall is disposed closer to the central portion than the parallel wall, and the inclined wall extends so as to be gradually separated from the cutting edge toward the central portion. With
The angle α between the oblique wall and the cutting edge may be set so that α> β when the angle between the cutting edge and the third breaker wall is β.
In this configuration, a wide breaker groove is secured between the oblique wall and the cutting blade, so that good chip discharge performance can be maintained.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a first embodiment of a chip according to the present invention will be described with reference to FIGS.
1 is a perspective view of a chip according to the present embodiment, FIG. 2 is a plan view of the chip, FIG. 3 is an enlarged view of a main part of FIG. 2, FIG. 4 is a sectional view taken along line XX of FIG. 2 is a sectional view taken along line BB, FIG. 6 is a sectional view taken along line AA in FIG. 2, FIG. 7 is a sectional view taken along line CC in FIG. 2, and FIG. 8 is a sectional view taken along line DD in FIG.
[0016]
The chip of the present embodiment has a rhombic plate shape, and a cutting edge 13 is formed at an intersection ridge line between the upper surface 11 and the side surface 12.
A breaker groove 16 is formed between the corner portion 14 and the central portion 15 of the upper surface 11 so as to be recessed from the periphery toward the lower surface side. In the breaker groove 16, first, second, and second breakers are provided. Three breaker walls 21, 22, 23 are formed.
[0017]
As shown in FIGS. 1 to 3, the first breaker wall 21 is arranged closest to the corner portion 14 compared to the other breaker walls 22 and 23.
As shown in FIGS. 5 and 6, the width is gradually increased from the corner portion 14 to the central portion 15, and has a heart shape as shown in FIG. 2 in plan view.
[0018]
Further, as shown in FIGS. 4 and 5, the curvature radius R1 of the corner portion 14 along the bisector L and the curvature radius R2 of the corner portion 14 along the direction perpendicular to the bisector L are R1> R2. It is formed so that it becomes.
That is, the wall surface along the bisector L rises with a gentler gradient than the wall surface along the direction orthogonal to the bisector L.
[0019]
On the other hand, both the second breaker wall 22 and the third breaker wall 23 are arranged behind the first breaker wall 21, that is, on the side of the central portion 15, and the height of each breaker wall 21, 22, 23 is As shown in FIG. 7, the first breaker wall 21, the second breaker wall 22, and the third breaker wall 23 are formed so as to be gradually higher in this order.
Note that reference numeral H1 in FIG. 7 indicates a difference in height between the first breaker wall 21 and the second breaker wall 22, and H2 indicates a difference in height between the second breaker wall 22 and the third breaker wall 23.
[0020]
The second breaker wall 22 is formed in a pair so as to be symmetrical with respect to the bisector L, and includes a parallel wall 22a extending in parallel with the cutting edge 13 and an oblique wall 22b connected to the rear of the parallel wall 22a. .
The oblique wall 22b extends so as to gradually separate from the cutting edge 13 as it goes backward, and the angle α between the cutting edge 13 and the cutting edge 13 and the third breaker wall 23 is β. In this case, it is preferable to set α> β.
[0021]
The third breaker wall 23 has a substantially triangular shape in a plan view, and is sandwiched between the second breaker walls 22 that form a bisector L side of the second breaker wall 22, that is, the second breaker wall 22. It is arranged behind one breaker wall 21.
Moreover, the wall surface extends so as to gradually separate from the cutting edge 13 from the front (the corner portion 14 side) to the rear side (the center portion 15 side), and the angle β formed with the cutting edge 13 is 0 <β ≦ θ / 2 is set.
Incidentally, θ is the angle of the corner portion 14.
[0022]
As described above, the third breaker wall 23 is formed so as to be higher than the first breaker wall 21 and the second breaker wall 22. Therefore, this chip includes the first breaker wall 21 and the third breaker wall. A two-stage breaker is formed by the wall 23, and a two-stage breaker is also formed separately by the second breaker wall 22 and the third breaker wall 23.
[0023]
According to the chip having the above configuration, the radius of curvature R1 of the first breaker wall 21 along the bisector L and the radius of curvature R2 of the first breaker wall 21 in the direction perpendicular to the bisector L are R1> Since it is formed so as to be R2, even if the distance from the tip of the corner portion 14 to the first breaker wall 21 is shortened, chip clogging and increase in cutting resistance at high cutting due to too strong braking effect can be prevented. Can be avoided.
For this reason, the distance from the tip of the corner portion 14 to the first breaker wall 21 can be set short, and the chip separation at the time of low cutting can be reliably performed.
[0024]
By setting the radius of curvature R2 smaller than R1, not only the distance from the cutting edge 13 at the time of low cutting to the first breaker wall 21 can be optimized, but also the distance from the cutting edge 13 at the time of high cutting The distance to one breaker wall 21 can also be optimized.
Therefore, even at the time of high cutting, chip clogging does not occur, cutting resistance can be prevented from increasing, and the direction in which chips are discharged can be reliably controlled.
[0025]
Further, since a part of the second breaker wall 22, that is, the parallel wall 22a is formed parallel to the cutting edge 13, the spread of the breaker groove 16 formed between the parallel wall 22a and the cutting edge 13 is suppressed. can do.
For this reason, even at the time of a high cut, the chips can be curled by the parallel wall 22a and reliably cut.
[0026]
In addition, since the parallel wall 22a plays a role of guiding the chip discharging direction, the chip discharging direction can also be controlled. .
In addition, while preventing the chip breaker groove 16 between the parallel wall 22a and the cutting edge 13 from being excessively widened, and ensuring a good chip separation property, the inclined wall 22b is gradually separated from the cutting edge 13 as going backward. Since the wide breaker groove 16 is secured between the oblique wall 22b and the cutting blade 13, good chip discharge performance can be maintained.
[0027]
Furthermore, in the chip of the present embodiment, a two-stage breaker formed by the first breaker wall 21 and the third breaker wall 23 and a two-stage breaker formed by the second breaker wall 22 and the third breaker wall 23 are formed. Therefore, even if the chips have passed over the first or second breaker wall 22, the chips can be curled and separated by the third breaker wall 23 higher than these breaker walls.
[0028]
In addition, by configuring such a two-stage breaker, the height of the second breaker wall 22 can be reduced, so that an increase in cutting resistance due to the second breaker wall 22 can be effectively prevented.
Further, since the third breaker wall 23 extends inclining toward the bisector L of the corner portion 14 from a direction parallel to the cutting edge 13, the cutting resistance by the third breaker wall 23 at the time of high cutting increases. Can also be effectively prevented.
[0029]
From the above, in the chip of the present embodiment, the chip discharge direction can be reliably controlled, and excellent chip disposability can be exhibited under a wide range of cutting conditions from low cutting to high cutting. .
[0030]
Next, a chip according to a second embodiment of the present invention will be described with reference to FIGS.
9 is a plan view of the chip as viewed from above, FIG. 10 is a view in the direction of arrow A in FIG. 9, FIG. 11 is a view in the direction of arrow B in FIG. 9, and FIG. 12 is a bottom view of the chip as viewed from the bottom.
[0031]
The chip of the present embodiment has an equilateral triangular plate shape, the size of the third breaker wall 23 is relatively small with respect to the first breaker wall 21, and the first breaker wall 21 has a plurality of wall surfaces 21a. , 21b, and the breaker wall corresponding to the second breaker wall 22 in FIG. 2 is composed of only the parallel wall 31 extending in parallel with the cutting edge 13 and is different from the chip shown in FIG.
[0032]
A plurality of first breaker walls 21 are formed on the side surface of the dot portion 32 having a flat upper surface disposed on the corner portion 14, and the bisector L of the wall surface 21 a adjacent to the corner portion 14 is formed among the plurality of first breaker walls 21. Is configured to be smaller than the radius of curvature along the direction orthogonal to the bisector L of the wall surface 21b connected to the rear side.
Although there is a difference in the configuration as described above, it is a matter of course that the chip of the present embodiment can obtain the same operation and effect as the chip shown in FIG.
[0033]
【The invention's effect】
As apparent from the above description, according to the present invention, the following effects can be obtained.
That is, it is possible to reliably perform chip cutting at the time of low cutting while avoiding chip clogging at the time of high cutting and an increase in cutting resistance.
Further, even at a high cutting depth, there is no chip clogging, the cutting resistance is reduced, and the direction in which the chips are discharged can be reliably controlled.
Further, at the time of further high cutting, chips can be surely divided.
[0034]
In addition, a third breaker wall is provided on the bisector side of the second breaker wall so as to be sandwiched between the pair of second breaker walls, and the third breaker wall is disposed on the corner side. To extend from the cutting blade gradually toward the central part from toward, and to be higher than the first and second breaker walls, so that the height of the second breaker wall can be reduced, An increase in cutting resistance due to the second breaker wall can be effectively prevented.
Further, it is possible to effectively prevent an increase in cutting resistance due to the third breaker wall at the time of high cutting.
Still further, the second breaker wall includes a slanted wall which is disposed closer to the center than the parallel wall and gradually extends away from the cutting blade toward the center. When the angle between the cutting edge and the wall of the third breaker is β, by setting α> β, good chip discharge performance can also be maintained.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a first embodiment of a chip according to the present invention.
FIG. 2 is a plan view of the throw-away tip shown in FIG.
FIG. 3 is an enlarged view of a main part of FIG. 1;
FIG. 4 is a longitudinal sectional view showing a section taken along line XX of FIG. 2;
FIG. 5 is a longitudinal sectional view showing a section taken along line BB of FIG. 2;
FIG. 6 is a longitudinal sectional view showing a section taken along line AA of FIG. 2;
FIG. 7 is a longitudinal sectional view showing a section taken along line CC of FIG. 2;
FIG. 8 is a longitudinal sectional view showing a section taken along line DD of FIG. 2;
FIG. 9 is a plan view showing a second embodiment of the chip according to the present invention.
FIG. 10 is a view as viewed in the direction of arrow A in FIG. 9;
11 is a view as viewed in the direction of arrow B in FIG. 9;
FIG. 12 is a bottom view of the chip shown in FIG. 9;
FIG. 13 is a plan view showing a conventional example of a chip.
FIG. 14 is a longitudinal sectional view showing a section taken along line XX of FIG. 13;
FIG. 15 is a longitudinal sectional view showing a section taken along line AA of FIG. 13;
FIG. 16 is a longitudinal sectional view showing a section taken along line BB of FIG. 13;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 Top surface 12 Side surface 13 Cutting edge 14 Corner part 15 Central part 16 Breaker groove 21 First breaker wall 22 Second breaker wall 22a Parallel wall 22b Oblique wall 23 Third breaker wall L bisector

Claims (3)

In the form of a polygonal plate, a cutting edge is formed at the intersection ridge line between the upper surface and the side surface, and a throwaway chip having a breaker groove between a corner portion and a central portion of the upper surface,
In the breaker groove, a curved first breaker wall disposed close to the corner side,
The first breaker wall is formed such that a radius of curvature R1 along a bisector of the corner portion and a radius of curvature R2 along a direction intersecting the bisector satisfy R1> R2. With
A second breaker wall disposed closer to the central portion than the first breaker wall,
The throw-away tip , wherein the second breaker wall has a parallel wall extending parallel to the cutting blade . On the bisector side of the second breaker wall, a third breaker wall disposed so as to be sandwiched between the pair of second breaker walls,
The third breaker wall extends so as to gradually separate from the cutting edge as going from the corner portion side to the center portion side, and is formed to be higher than the first and second breaker walls. The indexable insert according to claim 1, wherein: The second breaker wall includes an oblique wall that is disposed closer to the central portion than the parallel wall and that extends gradually away from the cutting edge toward the central portion,
The angle α between the oblique wall and the cutting edge is set so that α> β when the angle between the cutting edge and the third breaker wall is β. The throw-away tip according to claim 2.

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