JP2519773Y2 - Throw-away tip - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throw-away insert in which a ridge or the like for cutting chips is provided on a rake face of a tip body.

[0002]

2. Description of the Related Art As such a throw-away tip (hereinafter abbreviated as a tip) having a convex portion on the rake face, for example, one shown in FIG. 7 is known.
This chip 1 is described in Japanese Utility Model Laid-Open No. 61-151806, and a rake face 3 is formed on one surface of a flat plate-shaped chip body 2 having a polygonal shape (parallelogram in this example) in plan view. A cutting edge 6 having a nose portion 5 at the corner of the polygon is formed at the intersecting ridge line formed by the rake face 3 and the peripheral surface of the chip body 2 which is the flank face 4. FIG. 8 is a cross section perpendicular to the cutting edge 6 of the chip 1, but as shown in this figure, the rake face 3 is connected to the cutting edge 6 via the land portion 7 and is separated from the cutting edge 6. As it goes toward the inside of the chip body 2, the direction from the one surface side to the other surface side of the chip body 2, that is, the inside of the thickness direction of the chip body 2 (hereinafter abbreviated as the chip thickness direction). It is an inclined surface that inclines in the opposite direction, and the inclination angle α _{0 of} this surface is the rake angle of the cutting edge 6 of the chip 1. Further, a flat surface perpendicular to the chip thickness direction is formed on the one surface of the chip body 2 so as to be continuous with the rake surface 3, and the chip thickness is larger than the extension surface of the inclined surface formed by the rake surface 3. The breaker surface 8 is raised outward in the vertical direction. It should be noted that the rake surface 3 forming the inclined surface and the breaker surface 8 forming the flat surface have a curved surface 9 having a large radius of curvature.
Are smoothly connected by.

Then, as shown in FIGS. 7 and 9, the rake face 3 and the curved face 9 project outward from the rake face 3 and the curved face 9 in the chip thickness direction at a position separated from the cutting edge 6 by a predetermined section. The protrusions 10 having a spherical shape are formed. In this example, a plurality of such protrusions 10 are provided in the direction along the cutting edge 6. Further, in this example, the protrusion 10 is provided at a position further away from the cutting edge 6 than the protrusion 10.
A spherical projection 11 having a larger diameter than the above spherical surface is formed so as to project from the breaker surface 8 to the outside in the chip thickness direction. In FIG. 7, reference numeral 12 is a mounting hole for mounting the chip 1 on a tool such as a cutting tool. These projections 10 and 11 are provided for the purpose of dividing the chips generated during cutting into appropriate small pieces, and are scraped off by the cutting edge 6 and flow out from the rake face 3 along the curved face 9. The scraps produced by these chips are
Riding on No. 1, it is forcibly curled and finely divided.

Here, in the chip 1, the projections 10, 11
Is a rake face by making it a spherical surface.
Is formed between them. And cutting blade 6
The chips scraped off by the vehicle run on the projections 10 and 11 through the valleys 13 and are curled to a smaller curl diameter, so that the chips are effectively divided. Therefore, the larger the protrusion amount P of the projections 10 and 11 outward in the chip thickness direction is, the deeper the valley 13 becomes, and the generated chips are rapidly curled, so that it is more effective. It is possible to separate the chips.

[0005]

By the way, the chips produced by cutting with such a chip have a large wall thickness when the feed amount is large, and are easily divided by being curled. However, on the contrary, when the feed amount is small, thin chips are generated, and such chips are difficult to be cut immediately even if curled, and they are continuously generated to some extent and then cut after being curled. become. The shape of such continuously generated chips is
It can be classified into several forms depending on the cutting conditions such as the feed amount and the cut amount, the chip shape and the size, and the like. That is, when it is generated by being straightened along the cutting surface without being curled while being scraped off by the cutting edge, or in a spiral shape along the cutting surface, or from the cutting surface along the cutting edge. It may be generated in a cylindrical shape in the direction of separating, or may be generated while drawing a conical shape in a direction of separating obliquely with respect to the cutting edge and the cutting surface.

However, when the chips are generated linearly or spirally along the cutting surface as described above, such chips contact the cutting surface and deteriorate the cutting accuracy,
Alternatively, the generated chips may be caught between the tip and the work material to cause an increase in cutting resistance. In order to avoid such a problem, chips may be generated in a direction away from the cutting surface of the work material, but in the tip of the above example, the protrusion is formed in a spherical shape. Therefore, the chips in contact with the spherical surface may flow out in any direction, and it has been extremely difficult to control in which direction the chips are generated.

[0007]

The present invention has been made in order to solve the above-mentioned problems, and it is an intersection of the rake face and the flank face of a chip body having a polygonal flat plate shape in plan view from the rake face side. In the ridge portion, a cutting edge having a nose portion at the corners of the polygon is formed, and in the tip that is a sloping surface that gradually goes inward in the chip thickness direction as the rake face is separated from the cutting edge, On this rake face, a ridge portion protruding from the rake face toward the outside in the chip thickness direction and formed so that the ridge line portion connecting the protruding tips is perpendicular to the chip thickness direction is shown in the plan view. A virtual straight line that is formed from the outer peripheral side of the chip body toward the inside, and the ridge line part passes through the intersection of the rake face and the ridge line part in the above-mentioned plan view and is perpendicular to the cutting edge as the ridge part goes inward. Gradually to As directed in a direction between, and is characterized in that molding the ridge.

[0008]

In the chip of the present invention, the ridges of the ridges are formed in the direction perpendicular to the chip thickness direction, so that there is a valley between the rake face and the ridges as in the conventional example. The chips that have not been formed and flowed out from the rake face are once gently curled when they ride on the ridge of the ridge. After that, the chips are guided by the ridges and flow on the ridges, and during this time, the chips are discharged while being curled gradually due to contact with the ridges.

Here, the ridge line portion is an intersection of the ridge line portion and the rake face as the ridge portion goes inward from the outer peripheral side of the chip body in a plan view from the rake face, that is, as the ridge portion is separated from the cutting edge, That is, it is formed in a direction away from an imaginary straight line that is perpendicular to the cutting edge that passes through the starting point of this ridge portion. Therefore, the chips discharged while curled while being guided by such a ridge line are discharged along the direction in which the ridge line is formed, so that the generated chips have a directionality. It becomes possible to discharge. Therefore, by setting this direction appropriately, it is possible to prevent chips from being generated along the cutting surface of the work material and guide them in a direction away from the cutting surface, which may adversely affect the cutting work. It becomes possible to suppress.

[0010]

1 and 2 are a plan view and a side view showing an embodiment of the present invention. The tip 21 of the present embodiment is integrally formed from a hard material such as a cemented carbide, and as shown in these figures, the tip body 22 becomes one of the rake faces 23 of the tip 21. The surface is formed in a substantially square shape in plan view from the rake face 23, and the other face serving as the seating face 24 is in the thickness direction of the chip body 22.
That is, the chip 21 is a flat surface perpendicular to the chip thickness direction, and the peripheral surface serving as the flank 25 of the chip 21 is a flat negative chip formed perpendicular to the seating surface 24. At each corner of the square forming the rake face 23, a nose part 26 formed in a quarter-arc shape is formed, and an intersection ridge part formed by the rake face 23 and the flank 25, that is, the square A cutting edge 27 is formed on the four sides of the nose portion so as to be continuous with the nose portion 26.

Here, in this embodiment, the nose portions 26 formed at the four corners of the square and the nose portions 2 are formed.
The cutting blades 27 connected to each of the blades 6 can be reused as a blade body a total of four times. Accordingly, the cutting edge 27 formed on one crossing ridge portion is shared by the two nose portions 26 sandwiching the crossing ridge portion, so that the range of the cutting edge 27 normally used in one cutting, that is, the cutting edge 2
The range of use of 7 is from the nose portion 26 to about 1/2 of the length of the crossing ridge portion, that is, to approximately the center of the crossing ridge portion. In addition, in this embodiment, the cutting edge 27 is shown in FIG.
As shown in the side view from the flank 25, a portion near the nose portion 26 sandwiching the cutting edge 27 is formed in a direction perpendicular to the chip thickness direction. It is formed in a curved line shape that is depressed toward the seating surface 24 side, that is, inward in the chip thickness direction toward the center.

On the other hand, FIG. 3 shows the AA of this embodiment shown in FIG.
A cross section is shown. As shown in this figure, in this embodiment, a land 28 is formed on the one surface of the chip body 22 along the cutting edge 27 so as to circulate the square edge formed by this one surface with a constant width. It is provided. The land 28 is formed as a flat surface perpendicular to the chip thickness direction, and the rake surface 23 is formed so as to be continuous with the cutting edge 27 via the land 28. Further, the rake face 23 is an inclined face inward in the chip thickness direction as the distance from the cutting edge 27 increases in the cross-sectional view, and furthermore, the rake face 23 is on the opposite side to the cutting edge 27, that is, the rake face. A flat surface parallel to the land 28, that is, perpendicular to the chip thickness direction is formed inside the chip body 22 in a plan view from the surface 23 direction. The flat surface inside the tip body 22 is a surface that gradually rises from the extended surface as it is separated from the cutting edge 27 when viewed from the extended surface of the inclined surface formed by the rake surface 23.
The chips that have flowed along are curled to become the breaker surface 29 that receives the breaker effect. At the center of the chip body 22 in the plan view, a mounting hole 30 for mounting the chip 21 on a tool such as a cutting tool is formed through the chip thickness direction.

In this embodiment, the rake face 23 is
Two cutting edges sandwiching one nose portion 26 are provided with a ridge portion 31 projecting outward from the rake face 23 and extending inward from the outer peripheral side of the chip body 22 in the plan view. Within the above-mentioned usage range of 27, three for each cutting edge 27, that is, six for each intersecting ridge portion, are formed so as to be arranged at substantially equal intervals along the direction in which the cutting edge 27 is formed. There is. These ridges 31
Is such that the tip protruding from the rake face 23 to the outermost side in the chip thickness direction, that is, the ridge line portion 32 connecting the protruding tips of the ridges 31 is perpendicular to the chip thickness direction as shown in FIG. That is, the ridge line portion 32 is formed so as to be included in a surface perpendicular to the chip thickness direction.

Further, as shown in FIG. 1, when these ridges 31 pass through the intersection points 33 of the rake face 23 and the ridge line portion 32 in the plan view, and a virtual straight line L perpendicular to the cutting edge 27 is assumed. In the direction in which the cutting edge 27 is gradually formed, the ridge line portion 32 draws a curve that is convex toward the virtual straight line L in the plan view as the protruding portion 31 moves toward the inside of the chip body 22. It is formed so as to be separated toward the nose portion 26 side. However, the ridges 31 are arranged in such a shape within the range of use of the cutting edge 27 described above, and therefore, the ridges 31 are arranged with respect to the nose portion 26 in the plan view. It will be arranged in a concave arc shape,
Further, they are arranged symmetrically with respect to a plane perpendicular to the cutting edge 27 through the center of the cutting edge 27. Further, each of these ridges 31 is formed so as to form an arc surface in a cross-sectional view perpendicular to the ridge line portion 32, and as shown in FIG. Tip 3 of
4 draws a spherical surface that smoothly connects to this arc surface,
It is formed so as to be buried in the breaker surface 29.

FIG. 4 is a plan view of the present embodiment shown in FIG. 1, in which the ridge portion 3 is used within the range of use of the cutting edge 27.
It is a BB cross section perpendicular to the cutting edge 27 not including 1. As shown in this figure, in this embodiment, the rake face 23 is connected to the first rake face 23A on the side of the cutting blade 27 forming the rake angle α and the first rake face 23A, and the rake angle α And a second rake face 23B on the breaker face 29 side forming a smaller rake angle β. Further, in the present embodiment, all the ridge line portions 32 of the ridge portion 31 intersect the first rake face 23A, that is, the ridge line portion 32 of the ridge portion 31 and the rake face 2
All the intersections 33 with 3 are arranged on the first rake face 23A. In addition to this, in the present embodiment, the rake surfaces 23A and 23B are respectively set so that the rake angles α and β become gradually smaller as they are separated from the nose portion 26 within the use range of the cutting edge 27. width W and the width W ₁ of the first rake face 23A of the surface 23 is shaped so as to gradually increase, respectively. In addition,
The width W _{1 of} the first rake face 23A means the width from the cutting edge 27 to the first rake surface 23A in the cross section perpendicular to the cutting edge 27.
Is the distance in the direction perpendicular to the chip thickness direction to the intersection 35 between the second rake face 23B and the rake face 23B.
Means from the cutting edge 27 to the second rake face 23 in the above cross section.
The distance to the intersection 36 between B and the breaker surface 29 in the direction perpendicular to the chip thickness direction.

Here, the rake angles α, β, the width W of the rake face 23 and the width W ₁ of the first rake face 23A are
The cutting edge 27 gradually decreases and gradually increases within the range of use. Therefore, the rake angles α and β are gradually reduced from the one nose portion 26 toward the center of the one side and gradually increased toward the other nose portion 26 beyond the center. On the contrary, the width W of the rake face 23 and the width W ₁ of the first rake face 23A gradually increase as the distance from the one nose portion 26 increases, and becomes maximum at the center of the one side. Nose part 26
The distance is gradually reduced as it approaches the other nose portion 26. Furthermore, in the present embodiment, the size of the rake angle α is 3 at the maximum portion near the nose portion 26.
0 ° to 10 °, and the smallest part near the central part of the above-mentioned one side is set within the range of 20 ° to 5 °,
On the other hand, the size of the rake angle β is set to be 1/4 to 3/4 of the size of the rake angle α in the cross section perpendicular to the cutting edge 27.

In the chip 21 having such a structure, the ridge line portion 32 connecting the tips of the protruding portions 31 protruding outward from the rake face 23 in the chip thickness direction is formed so as to be perpendicular to the chip thickness direction. That is, since the ridge line portion 32 is formed so as to extend straight from the rake face 23 in the direction perpendicular to the chip thickness direction, the above-mentioned conventional method is provided between the ridge portion 31 and the rake face 23. The valleys as in the example are not formed. Therefore, it is scraped off by the cutting edge 27,
The chips flowing out along the rake face 23 are once loosely curled when they come into contact with the ridge line portion 32 of the ridge portion 31, then slide along the ridge line portion 32 and are guided inside the chip body 22 in a plan view. It However, during this sliding, the chips contact the ridge line portion 32 of the ridge portion 31 and are curled to a smaller curl diameter, so that the chips are discharged while drawing a circle on the ridge line portion 32. .

In the chip 21 of this embodiment, the ridge portion 31 is formed in a curved shape whose ridge line portion 32 is convex with respect to the imaginary straight line L. The normal direction of this curve is set to the nose portion 26 of the cutting edge 27.
Will be pushed to the opposite side. That is, the generated chips are ejected while being curled in a cylindrical shape along the cutting edge 27, or are curled in a conical shape on a line intersecting the cutting edge 27 inside the tip body 22 at an acute angle. , Will be divided. As described above, according to the tip 21 having the above-described configuration, the chips can be discharged and divided while being guided in the direction away from the cutting surface of the work material. That is, it becomes possible to give directionality to the discharge of the chips, and thus the generated chips come into contact with the cutting surface to deteriorate the cutting accuracy, or get caught between the tip 21 and the work material to cause the cutting resistance. It is possible to prevent a situation such as increasing the number of workpieces and perform a smooth cutting work. Further, since a certain directionality is given to the direction in which the chips are discharged, it becomes possible to easily process the chips during or after the cutting work. Furthermore, because the resistance that the tip receives due to contact with chips during cutting is also given a certain directionality, vibration of the tip during cutting work can be suppressed compared to when such resistance acts from random directions. It is also possible to prevent the deterioration of cutting accuracy more effectively.

Further, in this embodiment, as described above, since the valley portion unlike the conventional example is not formed between the rake face 23 and the ridge line portion 32 of the protruding portion 31, the feed amount is large. Even if relatively thick chips are generated, the chips scraped off by the cutting edge 27 and flowing out along the rake face 23 ride on the ridge line portion 32 of the ridge portion 31 and are gently curled and divided. Will be. For this reason, it is possible to prevent a situation in which such chips are rapidly curled to a small curl diameter as in the conventional case, and resistance is received to hinder the smooth generation of chips.

Further, in this embodiment, as described above, the cutting edge 2
7, the rake faces 23A and 23B are formed so that the rake angles α and β gradually become smaller as the rake faces 23A and 23B become more distant from each other. Therefore, the angle between the second rake face 23B and the breaker face 29 is also changed. It is formed so as to become smaller as the distance from the portion 26 increases. Along with this, the width W of the rake face 23 and the first rake face 2
The width W ₁ of 3A is formed so as to gradually increase.
Thus, when the feed amount is small, the thin chips generated near the nose portion 26 come into contact with the ridge portion 32 or the breaker surface 29 at a relatively early stage and are curled to a small curl diameter. Therefore, it is possible to more effectively prevent the chips from becoming stretched.
Conversely, when the feed amount is large, the large-thick chips generated at the portion of the cutting blade 27 separated from the nose portion 26 flow out of the rake face 23 over a certain distance, and then the ridge line portion. As a result, the curl is gently curled by contact with the breaker surface 32 or the breaker surface 29. Therefore, in combination with this and the breaker effect of the ridge portion 31, it is possible to further reduce the resistance of the chips. Further, in the present embodiment, in addition to this, in the portion of the cutting blade 27 that is separated from the nose portion 26, the rake angles α and β are reduced, so that a constant wall thickness is secured at the cutting edge portion of the cutting blade 27. There is also an advantage that the strength of the cutting edge can be maintained, and a situation in which the cutting edge 27 is damaged due to the load applied during cutting can be prevented.

Furthermore, in this embodiment, the first rake face 2 having a large rake angle α in which the rake face 23 is continuous with the cutting edge 27.
3A and a second rake face 23B having a small rake angle β connected to the first rake face 23A.
For this reason, even when the chips flowing along the first rake face 23A come into contact with the second rake face 23B, a breaker effect is generated, and the cutting performance of the chips can be improved. Also, the rake face 23 is divided into two rake faces 23A,
By setting it to 23B, the distance until the generated chips are curled for the first time can be made shorter than in the case of a single rake face as in the conventional example. Therefore, even when a thin chip having a small feed amount and a small thickness is generated, the chip is curled at a relatively early stage, so that it is possible to suppress the chip from becoming too long. As described above, according to the present embodiment, it is possible to reliably process the chip in the entire use range of the cutting blade 27 according to the state of the chip that changes due to the difference in the feed amount. In combination with the breaker effect, it is possible to provide an extremely versatile chip suitable for a wide range of applications.

Further, in this embodiment, as shown in FIG. 2, the central portion of the cutting edge 27 is inside the chip thickness direction, that is, the seating surface 24.
When the tip 21 is used for a turning tool such as a cutting tool or the like, the inclination of the cutting edge 27 within the above-mentioned use range is set to the regular angle side. Therefore, the rake angle in the axial direction and the rake angle in the radial direction of the turning tool can be set to the regular angle side. Therefore, there is an advantage that the resistance applied to the cutting edge 27 during cutting can be reduced and the outflow direction of the chips can be controlled in a more appropriate direction.

5 and 6 are a plan view and a side view showing another embodiment of the present invention. The same parts as those of the embodiment shown in FIGS. 1 to 4 are designated by the same reference numerals. And the description is omitted. In the chip 41 of the present embodiment, the ridge portion 42 formed so as to project from the rake face 23 with respect to the imaginary curve L, the ridge portion 43 of the ridge portion 43 is formed as the ridge portion 42 moves toward the inside of the chip body 22. It is characterized in that it is formed so as to be gradually away from the nose portion 26 in the direction in which the cutting edge 27 is formed while drawing a curved line which is convex toward the virtual straight line L in a plan view. To do.
However, similarly to the above-described embodiment, the protrusion 42 is arranged in such a shape within the range of use of the cutting edge 27 described above, and thus the protrusion 42 is nose-like in plan view. They are arranged in a convex arc shape with respect to the portion 26.

According to the chip 41 having such a structure, the generated chips are the same as in the above-mentioned embodiment, and the ridge line portion 4 of the ridge 42 is formed.
It is curled while drawing a circle in the shape of three, and is discharged in the normal direction of the ridge line portion 43. That is, the chips are the cutting edge 27
It is discharged while being curled in a cylindrical shape along the line, or is curled in a conical shape on the line intersecting the cutting edge 27 from the outside of the tip body 22 at an acute angle. Therefore, the chips do not come into contact with the cutting surface of the work material or get caught between the tip and the work material, and it is possible to obtain the same effect as that of the above embodiment. Further, in this embodiment, the curled chips are discharged not only to the work material but also to the chip body 22 in the direction of separating from the chip body 22. Therefore, there is also an advantage that it is possible to prevent a situation in which such chips are entangled with the tool such as the tool body 22 and the tool with the tool attached to the cutting operation, which is troublesome. Have.

In the above embodiment, a flat plate-like chip having a substantially square shape in plan view from the rake face 23 has been described, but a triangular or other polygonal flat plate-shaped chip may of course be used. Further, in these embodiments, the rake face 23 is constituted by two rake faces 23A and 23B, but this may be constituted by three or more rake faces.

[0026]

As described above, according to the present invention, the ridge line portion connecting the projecting tips of the ridges projecting from the rake face is formed to be perpendicular to the chip thickness direction, and the ridge line portion is formed. In a plan view from the rake face, the ridges are formed in a direction that separates from the virtual straight line perpendicular to the cutting edge as it goes toward the inside of the chip body, and in the discharge direction of the chips generated by this. It becomes possible to give a certain direction. As a result, it is possible to prevent chips from coming into contact with the cutting surface and degrading the cutting accuracy, or being caught between the tip and the work material to increase resistance, thus ensuring smooth cutting work. It becomes possible to do.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

2 is a side view of the embodiment shown in FIG. 1. FIG.

FIG. 3 is an AA sectional view of the embodiment shown in FIG. 1;

FIG. 4 is a sectional view taken along the line BB of the embodiment shown in FIG. 1;

FIG. 5 is a plan view showing another embodiment of the present invention.

6 is a side view of the embodiment shown in FIG.

FIG. 7 is a plan view showing an example of a conventional chip having a protrusion.

8 is a sectional view taken along line XX of the conventional example shown in FIG.

9 is a YY sectional view of the conventional example shown in FIG.

[Explanation of symbols]

21, 41 Chip 22 Chip body 23 Rake surface 23A First rake surface 23B Second rake surface 24 Seating surface 25 Flank surface 26 Nose portion 27 Cutting edge 28 Land 29 Breaker surface 31, 42 Ridge portion 32, 43 Ridge line portion 33 Intersection point between ridge line portion 32 and rake face 34 Protruding end portion of ridge portion 31 L A virtual imaginary straight line that passes through the intersection point 33 and is perpendicular to the cutting edge 27 in plan view from the rake face 23 forms the first rake face Rake angle β Rake angle of second rake face W Width of rake face 23 W ₁ Width of first rake face

Claims (1)

(57) [Scope of utility model registration request] 1. A cutting edge having a nose portion at the corner of the polygon is formed at the ridge line intersection of the rake face and the flank of a chip body having a polygonal flat plate shape in plan view from the rake face side. In addition, in the throw-away tip in which the rake face is gradually inclined toward the inner side in the thickness direction of the tip body as the rake face is separated from the cutting edge, the rake face has the thickness from the rake face. A ridge portion protruding outward in the direction and formed so that the ridge line portion connecting the protruding tips is perpendicular to the thickness direction, from the outer peripheral side of the chip body to the inside of the chip body in the plan view. The ridge portion is formed toward the inside of the chip body as the ridge portion is directed toward the inside of the chip body, and the ridge portion passes through the intersection of the rake face and the ridge portion in the plan view. To a virtual straight line perpendicular to The throw-away tip is characterized in that it is formed in a direction in which it gradually separates.