JP2006305716A - Throw away tip and rotational grinding tool equipped with the tip - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a throw away tip featuring little grinding resistance and more surely suppressing the generation of chattering vibrations. <P>SOLUTION: The first cutting blade 30 serving as the principal cutting blade is composed of a plurality of cutting blades 70-72 separated in the longitudinal direction B, so that cut chips to be discharged are minutely divided in the width directions, and accordingly, the cutting resistance during cutting work becomes smaller. Further a direction B1, one of the longitudinal direction of tip 23, agrees with a direction X1, one of the axial line direction of the tip holder, and the tip 23 is fixed to the tip holder 22. By this configuration, rotational grinding tool equipped with an axial rake in the positive direction is provided. The property of chamfering materials to be cut is improved, and thereby to reduce the cutting resistance against the materials to be cut. Even if heavy cutting work in which a cutting amount of one time operation becomes greater is performed, therefore, increase of cutting resistance is prevented, and chattering vibrations in cutting work is surely suppressed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a throw-away tip that constitutes a cutting tool, and more particularly, to a throw-away tip that constitutes an end mill for roughing.

  FIG. 6 is a side view showing the throw-away tip 1 of the prior art, and FIG. 7 is a perspective view showing the throw-away tip 1. Patent Document 1 discloses a cutting tool such as a face mill and an end mill, particularly a throw-away tip 1 (hereinafter simply referred to as a tip 1) that has a long main cutting edge and is used with a large number of blades attached. The chip 1 is formed in a substantially parallelogram. In the state in which the chip 1 is mounted on the chip holder, the rake face 4 with respect to the main cutting edge 3 has a positive rake angle, and the flank 5 is divided by the groove 6 together with the main cutting edge 3. The main cutting edge 3 constitutes a plurality of divided cutting edges 7, 8, 9 arranged in the longitudinal direction B. Such a chip 1 is mainly used for heavy cutting in which a large amount of chips are discharged. In this case, since the main cutting edge 3 is divided, the chips finely divided in the chip longitudinal direction B, that is, in the width direction of the chips are discharged.

  Moreover, the chip | tip disclosed by patent document 2 has the edge of an upper surface extended in step shape. Specifically, a plurality of component cutting edges constituting the main cutting edge and an intermediate edge located between the component cutting edges are provided. The rear end of one component cutting edge and the front end of the other component cutting edge are merged via an intermediate edge. The intermediate edge extends in the thickness direction so as to approach the bottom surface of the chip from the rear end of one component cutting edge. By dividing the main cutting edge into a plurality of pieces in this way, finely divided chips can be discharged.

Like each patent document mentioned above, the cutting resistance at the time of cutting can be reduced by dividing | segmenting the chip | tip discharged | emitted in the width direction small. As a result, an effect of suppressing chatter vibration during processing is obtained.
JP-A-7-299636 JP-A-6-190623

  In order to further improve the efficiency of the cutting work, heavy cutting with a larger cutting amount tends to be performed. In heavy cutting under such severe cutting conditions, the cutting resistance inevitably increases, and even when using the above-described prior art chip, the cutting resistance is increased and the occurrence of chatter vibration is sufficiently suppressed. There is a problem that can not be.

  Accordingly, an object of the present invention is to provide a throw-away tip that can reduce the cutting resistance and more reliably suppress the occurrence of chatter vibration.

The present invention has a cutting blade that is formed in a substantially plate shape and extends in a longitudinal direction predetermined at an intersecting ridge line portion between an upper surface portion that is one side portion in the thickness direction and a side surface portion that is bent from the upper surface portion to the other in the thickness direction. , A throw-away tip mounted on the bottom surface of the other side in the thickness direction in contact with the tip holder,
The side surface portion is formed with a groove that is immersed from the surface of the side surface portion and extends in the thickness direction.
The cutting blade has a plurality of divided cutting blades that are divided in the longitudinal direction by the grooves, and each of the divided cutting blades is inclined so as to move away from the bottom surface toward one side in the longitudinal direction with respect to the thickness direction. It is a throw-away chip to do.

  Further, the present invention is characterized in that each of the divided cutting blades is arranged on a predetermined virtual straight line.

  Further, the present invention is characterized in that each of the divided cutting blades extends in parallel with each other, and the dimension in the thickness direction of the one end in the longitudinal direction and the bottom surface of each of the divided cutting blades is uniformly formed. .

  In addition, the present invention is characterized in that the portion between the cutting edges between the two divided cutting edges arranged in the longitudinal direction has a surface on one side in the thickness direction extending along the divided cutting blade adjacent to one side in the longitudinal direction.

  Further, according to the present invention, the portion between the cutting edges between the two divided cutting blades arranged in the longitudinal direction has one surface in the thickness direction as the surface on the one side in the thickness direction moves from the divided cutting blade adjacent to one side in the longitudinal direction to the other side in the longitudinal direction. It is characterized by proceeding to.

The present invention also provides the throw-away tip,
A rolling tool comprising a tip holder for mounting a plurality of the throw-away tips.

  Further, the present invention is characterized in that the groove is formed along a circumferential direction around an axis of the chip holder.

Further, the present invention has a cutting edge that is predetermined in a crossed ridge line portion between an upper surface portion that is a one-side portion in the thickness direction and a side surface portion that is bent from the upper surface portion to the other in the thickness direction. , A throw-away tip mounted on the bottom surface of the other side in the thickness direction in contact with the tip holder,
The side surface portion is formed with a groove that is immersed from the surface of the side surface portion and extends in the thickness direction.
The cutting blade has a plurality of divided cutting blades divided by the groove,
Of the divided cutting blades, each of the divided cutting blades sandwiched between the grooves is a throw-away tip that is inclined so as to move away from the bottom surface toward one of the cutting blades in the thickness direction.

  In the present invention, among the divided cutting blades, the divided cutting blade having one end of the cutting blade is inclined so as to be once away from the bottom surface toward the one end of the cutting blade, and then is inclined so as to approach the bottom surface. It is characterized by that.

In the present invention, the main body is formed in a square plate shape.
Of the divided cutting blades, the divided cutting blade having the other end of the cutting blade is inclined so as to approach the bottom surface once and toward the one end of the cutting blade, and then inclined so as to move away from the bottom surface. And

  According to the first aspect of the present invention, since the cutting blade is constituted by a plurality of divided cutting blades divided in the longitudinal direction, the discharged chips are finely divided in the chip longitudinal direction. This reduces the cutting resistance during cutting. Furthermore, a tool for rolling having an axial rake in the positive direction is realized by matching one of the longitudinal directions of the tip with the direction from the proximal end portion to the distal end portion of the tip holder and attaching the tip to the tip holder. be able to. Thereby, the sticking property to the work material can be further improved, and the cutting resistance given from the work material can be reduced. Therefore, even when heavy cutting, that is, so-called roughing, in which the amount of cutting performed at one time is further increased, an increase in cutting resistance can be suppressed and chatter vibration during processing can be more reliably suppressed.

  Further, in the present invention, by tilting the cutting edge with respect to the bottom surface of the chip, the chip seating surface formed on the chip holder is provided with respect to the holder axis so as to reliably provide axial rake over the entire cutting blade. There is no need to greatly tilt the holder in the circumferential direction. As a result, a reduction in the thickness of the chip holder can be suppressed, a decrease in the rigidity of the chip holder can be suppressed, the life of the cutting tool can be extended, and the amount of cutting performed at a time can be increased.

  According to the present invention as set forth in claim 2, each of the divided cutting edges is arranged on a predetermined virtual straight line. As a result, of the two divided cutting blades arranged in the longitudinal direction, it is possible to prevent the chips scraped by one of the divided cutting blades in the longitudinal direction from colliding with the other divided cutting blade in the longitudinal direction. As a result, the chips discharged easily move toward the base end portion of the holder, and the chip discharge performance can be improved. Further, at the initial stage where the tip comes into contact with the work material, the divided cutting blade on the one side in the longitudinal direction comes into contact first. Thereby, compared with the case where a some division | segmentation cutting blade contacts simultaneously, the impact when a chip | tip collides with a workpiece can be made small. In addition, the thickness direction dimension of one of the plurality of divided cutting blades in the longitudinal direction and the bottom surface can be increased, and the rigidity of the divided cutting blade portion that first contacts the work material in the insert can be increased. The chip can be enlarged and damage to the chip can be prevented.

  According to the third aspect of the present invention, the divided cutting blades extend in parallel to each other, and the thickness direction dimensions of the one end portion in the longitudinal direction and the bottom surface of the divided cutting blades are uniformly formed. The Thus, at the initial stage where the tip comes into contact with the work material, one end portion in the longitudinal direction of each divided cutting blade comes into contact with the work material in order from one side in the longitudinal direction. Therefore, the reaction force applied to the chip and the chip holder from the work material can be prevented from being biased, and stress can be prevented from concentrating on a part of the chip and the chip holder. In addition, since each of the divided cutting blades is inclined with respect to the bottom surface, at the initial stage when the insert contacts the work material, the chip is attached to the work material as compared with the case where the plurality of divided cutting blades extend parallel to the bottom surface. Can reduce the impact of collision. This can prevent damage to the chip and chip holder. Further, in each of the divided cutting blades, the thickness direction dimension of the one side portion in the longitudinal direction and the bottom surface can be increased, and by increasing the rigidity of each of the divided cutting blade portions, the chip can be prevented from being damaged.

  Moreover, according to this invention of Claim 4, the thickness of the longitudinal direction other side edge part of the part between cutting edges, and the longitudinal direction one side edge part of the other division | segmentation cutting edge of a longitudinal direction other than the part between cutting edges The dimensional difference in direction can be increased. The step in the thickness direction of the chip formed in this way functions as a chip breaker that subdivides the chips, and can further improve the chip dischargeability.

  Moreover, according to this invention of Claim 5, the thickness direction one side surface of the part between cutting blades inclines and extends in one thickness direction as it goes to the other longitudinal direction. As a result, the thickness of the chip can be increased to further increase the rigidity of the chip, and the chip can be prevented from being damaged. Moreover, it can prevent that the part between cutting blades inhibits movement of a chip | tip because the chip | tip discharged | emitted moves along the thickness direction one side surface of the part between cutting edges. As a result, the chip dischargeability of the chip can be further improved.

  Moreover, according to this invention of Claim 6, a chip | tip can be subdivided by mounting | wearing the chip | tip with the chip | tip mentioned above. Moreover, an axial rake can be provided in a positive direction using a general-purpose holder, and the cutting load can be further reduced. This makes it possible to further reduce chatter vibration that occurs during machining even in severe cutting conditions, that is, heavy cutting with a heavy cutting load, so-called roughing, and to perform stable cutting efficiently. it can.

  According to the seventh aspect of the present invention, the groove formed in the side surface portion of the chip is formed along the circumferential direction around the axis of the chip holder. With this configuration, the portion where the work material is left uncut between the divided cutting blades passes through the groove formed in the side surface portion. Accordingly, it is possible to prevent the uncut portion from coming into contact with the side surface portion of the chip, and it is possible to prevent chatter vibration more reliably by preventing an impact from occurring on the chip. Further, the uncut portion can be roughed by being scraped off by another chip.

  According to the invention described in claim 8, since the cutting blade is constituted by a plurality of divided cutting blades divided by the groove, the discharged chips are finely divided in the width direction. This reduces the cutting resistance during cutting. Furthermore, it is possible to realize a rolling tool having an axial rake in the positive direction by attaching the tip to the tip holder so that one end of the cutting edge formed on the tip is positioned on the tip end side of the tip holder. it can. Thereby, the sticking property to the work material can be further improved, and the cutting resistance given from the work material can be reduced. Therefore, even when heavy cutting, that is, so-called roughing, in which the amount of cutting performed at one time is further increased, an increase in cutting resistance can be suppressed and chatter vibration during processing can be more reliably suppressed.

  Further, in the present invention, the tip seating surface formed on the tip holder is greatly inclined in the holder circumferential direction with respect to the holder axis in order to provide axial rake by inclining a part of the cutting edge with respect to the bottom surface of the tip. There is no need to let them. As a result, a reduction in the thickness of the chip holder can be suppressed, a decrease in the rigidity of the chip holder can be suppressed, the life of the cutting tool can be extended, and the amount of cutting performed at a time can be increased.

  According to the invention of claim 9, the divided cutting blade having one end of the cutting blade is inclined so as to approach the bottom surface on one end side of the cutting blade. As a result, the thickness direction dimension of the divided cutting blade to which the largest load among the plurality of divided cutting blades can be further increased, and the divided cutting blade and the cutting edge are formed on the side surface where the groove is formed. Since the angle formed with the end surface on the one end side of the blade can be increased, the rigidity of the divided cutting blade portion that first contacts the work material in the insert can be increased, and damage to the insert can be prevented.

  According to the invention of claim 10, the divided cutting blade having the main body portion formed in a substantially square plate shape and having the other end of the cutting blade is directed toward the other end of the cutting blade on the other end side of the cutting blade. Tilt away from the bottom. As a result, cutting edges can be formed at four locations on the chip, and the cost performance of one chip is increased.

  According to the invention of claim 11, the chips can be subdivided by mounting the above-described chip on the chip holder. Moreover, an axial rake can be provided in a positive direction using a general-purpose holder, and the cutting load can be further reduced. This makes it possible to further reduce chatter vibration that occurs during machining even in severe cutting conditions, that is, heavy cutting with a heavy cutting load, so-called roughing, and to perform stable cutting efficiently. it can.

  According to the invention of claim 12, the groove formed in the side surface portion of the chip is formed along the circumferential direction around the axis of the chip holder. With this configuration, the portion where the work material is left uncut between the divided cutting blades passes through the groove formed in the side surface portion. Accordingly, it is possible to prevent the uncut portion from coming into contact with the side surface portion of the chip, and it is possible to prevent chatter vibration more reliably by preventing an impact from occurring on the chip. Further, the uncut portion can be roughed by being scraped off by another chip.

  FIG. 1 is a perspective view showing a throw-away tip 23 according to the first embodiment of the present invention, and FIG. 2 is a side view showing the throw-away tip 23. FIG. 3 is a perspective view showing the end mill 20 in which the throw-away tip 23 according to the first embodiment of the present invention is attached to the tip holder 22.

  As shown in FIG. 3, the end mill 20 includes a throw-away tip 23 in which cutting edges 30 and 31 are formed, and a tip holder 22 to which the throw-away tip 23 is detachably attached. In the present embodiment, the tip holder 22 is mounted with a number of throw-away tips 23 (hereinafter simply referred to as tips 23). Specifically, the holder 22 is configured so that the six chips 23 are mounted side by side with an interval in the holder circumferential direction R and can be mounted in two rows in the holder axial direction X. Such an end mill 20 is used for roughing with a large amount of cutting performed at a time.

  The chip holder 22 is formed in a substantially cylindrical shape. A held portion to be held by the milling machine is formed at the base end portion in the axial direction X of the chip holder 22. A mounting portion 24 that holds the tip 23 in a state where the cutting blades 30 and 31 of the tip 23 protrude from the outer peripheral surface 32 and the end surface 33 is formed at the tip end portion in the axial direction X of the tip holder 22.

  The milling machine includes a movement drive unit that relatively moves and drives the clamped work material and the held end mill 20, and a rotation drive unit that drives the held end mill 20 to rotate about the axis L1. The end mill 20 contacts the work material while rotating around the axis L <b> 1 of the chip holder 22, so that the cutting blades 30 and 31 formed by the chips 23 intermittently cut the work material. As a result, the work material can be cut into a predetermined shape. For example, the end mill 20 can be used to perform shoulder processing, groove processing, stepping processing, and the like on the work material. When the cutting blades 30 and 31 of the tip 23 are worn or broken, the end mill 20 can restore cutting ability by attaching the tip 23 with a 180 degree angular displacement or replacing it with a new tip 23. it can.

  As shown in FIG. 1, the chip 23 is generally formed in a plate shape, and a projection shape projected on a plane perpendicular to the thickness direction A is formed in a substantially rectangular shape. A through hole 50 that penetrates in the thickness direction A is formed in the chip 23. The through hole 50 is a hole for fixing the chip 23 to the chip holder 22 and is formed in a cylindrical shape. The through hole 50 is formed at the center position in the longitudinal direction B and the width direction C of the chip 23. The tip 23 is formed in a 180-degree rotationally symmetric shape with respect to the reference axis L2, in other words, a two-fold rotationally symmetric shape, with the axis of the through hole 50 as the reference axis L2. Therefore, when the chip 23 is viewed from an arbitrary direction, the chip 23 has the same shape in the state rotated 180 degrees around the reference axis L2 and the state before the rotation.

  Hereinafter, a direction in which the reference axis L2 extends is referred to as a thickness direction A. Of the directions perpendicular to the thickness direction A of the chip 23, the direction extending along the long side of the surface in the thickness direction of the chip 23 when projected onto a projection plane perpendicular to the reference axis L2 is referred to as a longitudinal direction B. A direction perpendicular to the thickness direction A and the longitudinal direction B of the chip 23 is referred to as a width direction C.

  Cutting edges 30 and 31 are formed on the edge of the upper surface portion 90 which is the surface portion on one side in the thickness direction of the chip 23. Specifically, in the chip 23, the first cutting blades 30 (30 </ b> A and 30 </ b> B) are formed on the edges of the pair of long side portions 60 and 61 facing each other in the upper surface portion 90. Further, in the chip 23, the second cutting blades 31 (31 </ b> A, 31 </ b> B) are formed on the edges of the pair of short side portions 62, 63 facing each other in the upper surface portion 90. Each of the cutting blades 30 and 31 serves as an intersecting ridge line portion where the upper surface and the side surface of the chip 23 intersect. In a state where the chip 23 is mounted on the chip holder 22, one of the two first cutting edges 30 becomes a main cutting edge extending in the axial direction X of the chip holder 22, and one of the two second cutting edges 31 is It becomes a sub cutting edge extending in the radial direction Y of the chip holder 22.

  Hereinafter, in the thickness direction A, the direction from the bottom surface 86 where the cutting blades 30 and 31 are formed to the top surface 87 is referred to as a thickness direction one A1, and the direction from the top surface 87 to the bottom surface 86 is referred to as the other thickness direction A2. Further, in the longitudinal direction B, the direction proceeding from the second short side portion 63 to the first short side portion 62 is defined as one longitudinal direction B1, and the direction proceeding from the first short side portion 62 to the second short side portion 63 is defined as the other longitudinal direction. Let B2. Of the width direction C, the direction from the second long side portion 61 to the first long side portion 60 is one width direction C1, and the direction from the first long side portion 60 to the second long side portion 61 is one width direction. Let C2.

  In the present embodiment, when the chip 23 is projected onto a projection plane perpendicular to the reference axis L2, the longitudinal direction B substantially coincides with the first direction in which the first cutting edges 30 extend in parallel with each other on the projection plane. To do. Further, when the chip 23 is projected onto the projection plane perpendicular to the reference axis L2, the width direction C substantially coincides with the second direction in which the second cutting edges 31 extend in parallel to each other on the projection plane.

  When the chip 23 is projected onto a projection plane perpendicular to the reference axis L2, the first cutting edges 30 extend in parallel with each other and are formed over almost the entire area in the longitudinal direction B of the long side portions 60 and 61. Each second cutting edge 31 is formed in a part of each of the short side portions 62 and 63, and is parallel to each other and extends substantially perpendicular to the first cutting edge 30.

  Specifically, one second cutting edge 31 </ b> A formed on the first short side portion 62 is disposed at an end portion on the B1 side in the longitudinal direction of one first cutting edge 30 </ b> A formed on the first long side portion 60. It is continuous, and extends in the other width direction C2 with respect to one first cutting edge 30A. The other second cutting edge 31B formed on the second short side portion 63 is connected to the other B2 side end portion in the longitudinal direction of the other second cutting edge 30B formed on the second long side portion 61. The first cutting edge 30B extends in one direction C1 in the width direction. Actually, the first cutting edge 30 and the second cutting edge 31 are connected via a corner portion 68. The corner portion 68 is formed with a corner cutting edge extending along an arc having a predetermined radius of curvature, and the corner cutting edge connects the first cutting edge 30 and the second cutting edge 31 to each other.

  Of each of the short side portions 62 and 63, the non-cutting edge forming edge 69 where the second cutting edge 31 is not formed is connected to the edge of the long side portion opposite to the second cutting edge 31 from the second cutting edge 31. . This non-cutting edge forming edge 69 is inclined so as to retract in the longitudinal direction B with respect to the second cutting edge 31 as it proceeds from the second cutting edge 31 to the edge of the long side opposite to the second cutting edge 31. To do. That is, as one non-cutting edge forming edge 69A advances from one second cutting edge 31A to the other in the width direction C2, it advances to the other longitudinal direction B2 and continues to the other first cutting edge 30B. Further, the other non-cutting edge forming edge 69B formed in the second short side portion 63 advances in the longitudinal direction one B1 from the other second cutting edge 31B in the width direction one C1, and the one first cutting edge. It continues to 30A. These non-cutting edge forming edges 69 extend substantially parallel to each other.

  Each second cutting edge 31 extends in the width direction C along a plane perpendicular to the thickness direction A. The non-cutting edge forming edge 69 is inclined toward the other side A2 in the thickness direction as it advances from the second cutting edge 31 toward the first cutting edge 30. That is, the non-cutting edge forming edge 69A proceeds to the other width direction C2 and proceeds to the other thickness direction A2. Further, the other non-cutting edge forming edge 69B proceeds in the width direction one C1 and in the thickness direction other A2. When the chip 23 is projected onto the projection plane perpendicular to the longitudinal direction B, each second cutting edge 31 is arranged at the position on the most A1 side in the thickness direction, and each first cutting edge 30 is most outward in the width direction C. Each is arranged.

  In the present embodiment, each first cutting edge 30 extends from one short side portion 62, 63 where the corner portion 68 is formed to the other short side portion 62, 63 where the non-cutting edge forming edge 69 is formed. As it progresses in the longitudinal direction B, it inclines along one predetermined virtual straight line L3 toward the other thickness direction A2. The predetermined virtual straight line L3 is a straight line that inclines toward the other side A2 in the thickness direction as it proceeds from the corner portion 68 toward the non-cutting edge forming edge 69. That is, one first cutting edge 30A is inclined in the other thickness direction A2 as it advances in the other longitudinal direction B2. The other first cutting edge 30B is inclined in the other thickness direction A2 as it advances in the longitudinal direction one B1.

  Of the edges that go around the upper surface portion 90 of the chip 23, the corner portion 68 that connects the first cutting edge 30 and the second cutting edge 31 is located on the most A1 side in the thickness direction, and is not connected to the first cutting edge 30. The connecting portion 67 to which the cutting edge forming edge 69 is connected is located in the othermost thickness direction A2 most. Further, on the upper surface portion 90 of each of the long side portions 60 and 61, as the distance from the first cutting edge 30 in the width direction C is increased, a first rake face that is inclined in the other thickness direction A2 is formed. On the side surfaces in the width direction of the long side portions 60 and 61, first flank surfaces that are immersed in the width direction C are formed as they are separated from the first cutting edge 30 in the other thickness direction A2.

  Further, each short side portion 62, 63 is formed with a second rake face that inclines in the other thickness direction A2 as it is separated from the second cutting edge 31 in the longitudinal direction B. On the side surfaces in the longitudinal direction of the respective short side portions 62 and 63, second flank surfaces that are immersed in the longitudinal direction B are formed as they are separated from the second cutting edge 31 in the other thickness direction A2.

  In this way, the chip 23 has two diagonally opposed corners of the corners of the intersecting ridge formed by the side surface and the upper surface of the main body having a substantially rectangular shape in the plan view when the chip 23 is viewed from one side A1 in the thickness direction. A corner cutting edge is formed at a corner, and a first cutting edge 30 for forming a main cutting edge on both sides of the corner cutting edge and a second cutting edge 31 for forming a sub cutting edge are provided. . A portion of the upper surface 87 along the first cutting edge 30 is provided with a first rake face with a certain rake angle. As the first cutting edge 30 moves away from the corner cutting edge in the longitudinal direction B, the first cutting edge 30 is gradually moved away from the plane including the corner cutting edge and perpendicular to the reference axis L2, and is inclined so as to be close to the bottom face 86. It has a twisted shape.

  In the present embodiment, the chip 23 has the first cutting edge 30 formed at the intersecting ridge line portion between the upper surface portion 90 that is the one side A1 side in the thickness direction and the side surface portion 91 that is bent from the upper surface portion 90 in the thickness direction A. The In the side surface portion 91, a groove 92 is formed that extends in the width direction C from the surface of the side surface portion and extends in the thickness direction A. The groove 92 is formed from the thickness direction one A1 side surface of the side surface portion 91 to the thickness direction other A2 side surface. The first cutting edge 30 has a plurality of divided cutting edges 70, 71, 72 that are divided in the longitudinal direction B by the grooves 92.

  In the present embodiment, since the chip 23 is formed 180 degrees rotationally symmetric, the groove 92 and the divided cutting blades 70 to 72 are formed on both sides of the chip 23 in the width direction C with the reference axis L2 interposed therebetween. Hereinafter, the groove 92 and the divided cutting edges 70 to 72 on the one side C1 side in the width direction will be described, and the description of the groove 92 and the divided cutting edges 70 to 72 on the other side C2 side will be omitted.

  One or more grooves 92 are formed. In the present embodiment, two grooves 92 are formed in the side surface portion 91. The width C depth of the groove 92 is set deeper than a preset maximum feed amount per blade of the end mill 20. The groove 92 extends along the circumferential direction around the axis of the chip holder. Each of the divided cutting blades 70 to 72 is inclined in the thickness direction other side A <b> 2, that is, in a direction approaching the bottom surface 86 as it goes to the other longitudinal direction B <b> 2. In other words, each of the divided cutting blades 70 to 72 is inclined so as to go to one thickness direction A1 as going to the longitudinal direction one B1. In this Embodiment, each division | segmentation cutting blade 70-72 is each arrange | positioned on one virtual line L3 which inclines to thickness direction other A2 as it goes to the other longitudinal direction B2.

  As shown in FIG. 2, when the side surface is viewed from the width direction C, the cutting edge portion 73 that forms the divided cutting blades 70 to 72 on the chip 23, and between the divided cutting blades 70 to 72. And a portion 74 between the cutting edges. As described above, the divided cutting edges 70 to 72 that are the edges on the one A1 side in the thickness direction of each divided cutting edge portion 73 are arranged on one imaginary straight line L3. Therefore, as for the chip | tip 23, the thickness dimension of the division | segmentation cutting blade part 73 becomes small as it goes to the other longitudinal direction B2. For example, of the two divided cutting edge portions 73 adjacent to each other in the longitudinal direction B, the divided cutting blade portion 73 in one longitudinal direction B1 is thicker in the thickness direction A than the divided cutting blade portion 73 in the other longitudinal direction B2. Becomes larger.

  Further, one A1 side surface 75 in the thickness direction of each portion 74 between the cutting edges extends parallel to the one imaginary straight line L3, and retreats in the other thickness direction A2 from the one imaginary straight line L3. That is, each of the inter-cutting blade portions 74 is immersed in a direction perpendicular to the virtual straight line L3 as compared with the surface of each of the divided cutting blade portions 73 adjacent in the longitudinal direction B.

  Moreover, in this Embodiment, as shown in FIG. 1, the protrusion 51 which protrudes in the thickness direction A from a 1st rake face is formed. The protrusion 51 is provided for each of the divided cutting blades 70 to 72. Each protrusion 51 is opposed to the corresponding divided cutting blades 70 to 72 in the width direction C. Further, the divided cutting blade side portion of the protrusion 51 is formed in a tapered shape such that the width and height gradually decrease toward the opposed divided cutting blades 70 to 72. Further, the protrusion 51 is disposed on a substantially vertical bisector of the divided cutting blades 70 to 72. Further, in a top view projected onto a surface perpendicular to the thickness direction A, the divided cutting blades 71 and 72 other than the divided cutting blade 70 disposed continuously to the corner cutting blade and the divided cutting facing the tapered projection 51 are opposed to each other. The extension line toward the blade is orthogonal. Further, the protrusion 51 corresponding to the divided cutting edge 70 disposed continuously to the corner cutting edge is formed so that the width and height gradually decrease toward the corner cutting edge. By forming the protrusions 51 in this way, it is possible to prevent wear of the holder wall surface due to the contact of chips. Specifically, when the chips cut by the divided cutting blades flow on the first rake face toward the inner Y1 in the holder radial direction, they curl to the small extent. As a result, it is possible to prevent chips from coming into contact with the wall surface of the holder and wearing out the wall surface of the holder.

  With the bottom surface 86 of the chip 23 in contact with the seating surface 40 formed on the chip holder 22, the through hole 50 formed on the chip 23 and the screw hole formed on the mounting portion 24 are substantially coaxial. . The screw member in which the male screw is formed in this state is inserted into the through hole 50 of the chip 23 and screwed into the screw hole, whereby the chip 23 can be fastened to the mounting portion 24 of the chip holder 22. 23 can be mounted on the mounting portion 24 of the chip holder 22. The chip 23 attached to the chip holder 22 has a substantially longitudinal direction B extending along the axial direction X of the chip holder 22, and a width direction C extending substantially along the radial direction Y of the chip holder 22. In particular, the thickness direction A extends along the circumferential direction R of the chip holder 22. In addition, the chip 23 mounted on the chip holder 22 is in contact with the seating surface 40 formed on the chip holder 22 at substantially the entire bottom surface 86.

  Hereinafter, the axis of the chip holder 22 is simply referred to as an axis L1. Further, the axial direction X along the axis L1 of the chip holder 22 and the direction going from the proximal end portion of the chip holder 22 to the distal end portion is referred to as one axial direction X1, and the direction from the distal end portion of the chip holder 22 toward the proximal end portion. Is referred to as the other axial direction X2. A direction toward the axis L1 along the radial direction Y of the chip holder 22 is referred to as a radial inner direction Y1, and a direction away from the axis L1 along the radial direction Y of the chip holder 22 is referred to as a radial outer direction Y2. In addition, the circumferential direction R around the axis L1 of the tip holder 22 and the direction in which the end mill 20 rotates is referred to as one circumferential direction R1, and the direction opposite to the rotational direction of the end mill 20 is referred to as the other circumferential direction R2.

  The tip 27 of the chip holder 22 is formed with a recess 27 that is recessed from the outer peripheral surface 32 and the tip end surface 33 of the chip holder 22. The recess 27 is a space that includes a throw-away chip accommodation space and a chip accommodation space. A plurality of recesses 27 are provided side by side in the holder circumferential direction R. The throw-away chip accommodating space is a space in which almost the entire chip 23 is accommodated. The chip storage space is a space for temporarily storing chips scraped by the chip 23. The throwaway chip accommodation space and the chip accommodation space are formed adjacent to each other. Among the recesses 27, the region on the one R1 side in the circumferential direction becomes a chip accommodating space, and the region on the other R2 side in the circumferential direction becomes a throwaway tip accommodating space. Further, in the present embodiment, the chip accommodating space extends in the other axial direction X2 from the throw-away tip accommodating space and is opened outward. After the chips separated from the work material by the cutting blades 30 and 31 of the chip 23 are accommodated in the chip accommodating space and then accommodated in the chip accommodating space, the chip holder 22 is rotated along with the rotation of the chip holder 22. It is angularly displaced around the axis L1 and escapes from the opening of the chip accommodating space.

  A plurality of seating surfaces 40 are formed on the mounting portion 24. The seating surface 40 formed on the one side in the holder axial direction X1 is bent from the end surface 33 of the chip holder 22 and extends to the other side in the holder axial direction X2. Each seating surface 40 is bent from the outer peripheral surface 32 of the chip holder 22 and extends inwardly in the holder radial direction Y1. Each seating surface 40 extends in a planar manner along a virtual plane passing through the axial direction X of the chip holder 22 and extending in the chip holder radial direction Y. Further, each mounting portion 24 is formed with a screw hole 29 that is recessed from the seating surface 40 to the other circumferential direction R2. The screw hole 29 is formed with a female screw and serves as a hole for fixing the chip 23.

  As shown in FIG. 3, the tip 23 is mostly accommodated in the recess 27 in a state where the tip 23 is attached to the attachment portion 24, and one or the other first cutting edge 30 is the outer periphery of the tip holder 22. A main cutting edge is formed by projecting from the surface 32 radially outward Y2 by a predetermined projection amount. The tip 23 arranged on the most X1 side in the holder axial direction has one or the other second cutting edge 31 projecting from the tip surface 33 of the tip holder 22 in the axial direction one X1 by a predetermined projection amount, and the auxiliary cutting edge is inserted. Constitute. Further, of the two chips 23 arranged in the holder axial direction X, the second cutting blade 30 does not protrude from the holder end surface 33 of the chip 23 other than the chip on the one side in the holder axial direction X1. The two chips 23 arranged in the holder axial direction X are arranged so as to be shifted in the holder circumferential direction R, and the tip 23 in one side of the holder axial direction X1 is one in the holder circumferential direction R1 relative to the tip 23 in the other side of the holder axial direction X2. Placed in. In a state where each chip 23 is mounted on the mounting portion 24 of the chip holder 22, each of the divided cutting blades 70 to 72 is inclined to the other holder circumferential direction R2 as it proceeds to the other holder X2 direction X2. The bottom face 86 extends along a plane that passes through the holder axis L1 and extends in the holder radial direction Y.

  In the present embodiment, the two chips 23 adjacent to each other in the holder circumferential direction R have different numbers of grooves 92 formed in the side surface portion 91, and one chip 23 and the other chip 23 have divided cutting blades 70 to 70. The length and arrangement position of 73 in the holder axial direction X are different. As a result, the portion left uncut by the divided cutting blade of one tip 23 can be cut off by the divided cutting blade of the other tip 23, and the processing wall on the workpiece side can be processed without a step.

  As described above, according to the embodiment of the present invention, the end mill 20 in which the chip 23 is mounted on the chip holder 22 has the cutting blade 30 formed on the chip 23 as the main cutting blade. The end mill 20 contacts the workpiece while rotating around the holder axis L1, so that the main cutting edge cuts the workpiece intermittently. In addition, even when there is a part where the work material is left uncut between the divided cutting edges in one chip 23, a plurality of chips 23 are attached to the chip holder 22, so that the remaining part is removed The chip 23 can be scraped off. As a result, the work material can be cut into a predetermined shape. When the main cutting edge is worn, the cutting ability of the end mill 20 can be increased by mounting a new chip 23 on the chip holder 22 or mounting the chip 23 with an angular displacement of 180 degrees around the reference axis L2. Can be recovered.

  In this embodiment, the 1st cutting blade 30 is divided | segmented by the some divided cutting blades 70-72 divided | segmented into the longitudinal direction B finely. This reduces the cutting resistance during cutting. Further, by attaching the tip 23 to the tip holder 22 so that the longitudinal direction one B1 of the tip 23 coincides with the holder axial direction one X1, an end mill having a positive axial rake without using a special tip holder. 20 can be realized. Thereby, the sticking property to the work material can be further improved, and the cutting resistance given from the work material can be reduced. Therefore, even if heavy cutting that increases the amount of cutting performed at one time is performed, an increase in cutting resistance can be prevented, and chatter vibration during processing can be more reliably suppressed.

  Further, in the present embodiment, the first cutting blade 30 is inclined with respect to the bottom surface 86 of the tip 23 to provide positive rake in the positive direction, so that the seating surface 40 of the tip holder 22 is made larger than the holder axis L1. There is no need to tilt. As a result, a reduction in the thickness of the chip holder 22 can be suppressed, and a decrease in the rigidity of the chip holder 22 can be prevented, the life of the end mill 20 can be extended, and the amount of cutting performed at a time can be increased.

  In addition, by reattaching the tip 23 of the present embodiment to a light-cutting general-purpose tip having a zero twist angle, the axial rake can be cut in a state close to neutral. That is, by using one chip holder 22 and simply mounting the chip 23 of the present embodiment on the chip holder 22, it is possible to realize the roughing end mill 20 with a large axial rake. In order to perform heavy cutting by this, it is not necessary to make the special chip holder 22 easy, and the cost can be reduced.

  Further, according to the present embodiment, the groove 92 formed in the side surface portion 91 extends with respect to 86 along the circumferential direction around the axis of the chip holder. With this configuration, the portion where the work material is left uncut between the divided cutting blades passes through the groove 92 formed in the side surface portion 91. As a result, it is possible to prevent the uncut portion from interfering with the side surface of the chip 23 and to prevent the chip 23 from being impacted, thereby preventing chatter vibration more reliably. Incidentally, in order to obtain such an effect, the wall surface on the B1 side in the longitudinal direction of the groove 92 is formed substantially perpendicular to the bottom surface 86, and the wall surface on the other B2 side in the longitudinal direction of the groove 92 is formed as described above. The shape can be formed along the circumferential direction around the axis of the upper and lower molds, and can be easily realized by a normal chip forming method in which the upper die and the lower die are combined to form the upper and lower punches, and the groove 92 is formed. In addition, no new process is required. Therefore, an increase in chip manufacturing cost can be suppressed.

  Moreover, according to this embodiment, each division | segmentation cutting blade 70-72 is each arrange | positioned on the predetermined 1 virtual line L3. Further, one A1 side surface 75 in the thickness direction of each portion 74 between the cutting edges extends parallel to the one imaginary straight line L3, and retreats in the other thickness direction A2 from the one imaginary straight line L3. As a result, the chips discharged are prevented from coming into contact with the respective divided cutting blade portions 74 when moving in the holder axial direction X2, and the chips can be discharged from the recess vigorously. The waste discharging property can be improved.

  Further, at the initial stage where the tip 23 comes into contact with the work material, the divided cutting edge 70 of the most longitudinal direction B1 comes into contact first. Thereby, compared with the case where several division | segmentation cutting blades 70-72 contact simultaneously, the impact when the chip | tip 23 collides with a workpiece can be made small. Further, since the split cutting edge 70 of the most longitudinal direction B1 has a large thickness direction dimension, the rigidity of the split cutting edge portion 70 that first contacts the work material in the chip 23 can be increased, and the chip 23 is damaged. Can be prevented.

  FIG. 4 is a side view showing a throw-away tip 123 according to the second embodiment of the present invention. The throw-away tip 123 of the second embodiment has a configuration similar to the throw-away tip 23 of the first embodiment. Similar parts are denoted by reference numerals obtained by adding 100 to the reference numerals of the configuration of the first embodiment, and description thereof is omitted.

  The chip 123 has a different configuration of the side surface portion 191 compared to the chip 23 of the first embodiment, and the rest is the same. Specifically, in the chip 123, the first cutting edge 130 is formed at the intersection ridge line portion between the upper surface portion 190 which is a portion on the one side A1 in the thickness direction and the side surface portion 191 which is bent from the upper surface portion 190 in the thickness direction A. . In the side surface portion 191, a groove 192 is formed that extends in the width direction C from the surface of the side surface portion and extends in the thickness direction A. The groove 192 is formed from the thickness direction one side surface of the side surface portion 191 to the thickness direction other side surface. The first cutting edge 130 has a plurality of divided cutting edges 170, 171 and 172 that are divided in the longitudinal direction B by the groove 192.

  In the present embodiment, since the chip 123 is formed to be 180 degrees rotationally symmetric, as shown in FIG. 4, the groove 192 and the divided cutting edges 170 to 172 have a width direction C of the chip 123 across the reference axis L2. Formed on both sides. Hereinafter, the groove 192 and the divided cutting edges 170 to 172 on the one side C1 side in the width direction will be described, and the description about the groove 192 and the divided cutting edges 170 to 172 on the other side C2 side in the width direction will be omitted.

  One or more grooves 192 are formed. In this embodiment, two grooves 192 are formed in the side surface portion 191. The depth C in the width direction of the groove 192 is set deeper than the maximum feed amount per blade of the end mill 20. The groove 192 extends along the circumferential direction around the axis of the chip holder. Each of the divided cutting edges 170 to 172 is inclined in the thickness direction other side A2, that is, in the direction approaching the bottom surface 186, as it goes to the other longitudinal direction B2.

  As shown in FIG. 4, when the side surface is viewed from the width direction C, the tip 123 is formed between the divided cutting blade portions 173 forming the respective divided cutting blades 170 to 172 and the cutting blades between the divided cutting blades. A portion 174 is formed. The divided cutting blades 170 to 172 serving as the side edges on the one side A1 in the thickness direction of the divided cutting blade portions 173 respectively extend in parallel. Further, the thickness direction dimensions T1, T2, and T3 of the end portions 170a, 171a, and 172a on one side in the longitudinal direction of the divided cutting blades 170 to 172 and the bottom surface 186 are formed uniformly. In addition, one thickness direction one A1 edge 175 of the portion 174 between the cutting edges that is between the two divided cutting blades arranged in the longitudinal direction B extends incline toward the other thickness direction A2 toward the other longitudinal direction B2. Each portion 174 between the cutting edges retreats to the other side A2 in the thickness direction from an imaginary line L4 extending along the divided cutting blades in the one longitudinal direction B1. That is, the thickness direction between the other end B2 side end 179 in the longitudinal direction of the portion 174 between the cutting edges and the one end B1 side ends 170a to 172a in the longitudinal direction of the divided cutting blade located at the other end B2 in the longitudinal direction other portion 174 between the cutting edges. The dimensions T4 and T5 are increased.

  According to the chip 123 of the second embodiment of the present invention as described above, the same effect as that of the chip 23 of the first embodiment can be obtained. Moreover, in 2nd Embodiment, each division | segmentation cutting blade 170-172 extends in parallel with each other, and thickness direction dimension T1, T2 of the longitudinal direction one B1 side edge part 170a-172a and bottom face 86 of each division | segmentation cutting blade 170-172. , T3 are formed uniformly. As a result, at the initial stage when the tip 123 contacts the work material, the end portions 170a to 172a in the longitudinal direction of the divided cutting blades 170 to 172 respectively contact the work material in order from the one B1 side in the longitudinal direction. Touch. Therefore, the force applied to the chip 123 and the chip holder 22 from the work material can be prevented from being extremely biased, and stress can be prevented from concentrating on a part of the chip 123 and the chip holder 22. As a result, the chip 123 and the chip holder 22 can be prevented from being damaged.

  Compared with the first embodiment, in each of the divided cutting edges 170 to 172, the thickness direction dimensions T2 and T3 between the B1 side portion in the longitudinal direction and the bottom surface 86 can be increased, and the rigidity of the divided cutting edge portion 173 is increased. By increasing the size, damage to the chip 123 can be prevented. In addition, since each of the divided cutting blades 170 to 172 is inclined with respect to the bottom surface 186, compared with a case where the plurality of divided cutting blades extend in parallel to the bottom surface at the initial stage where the chip 123 contacts the work material, The impact when the tip 123 collides with the work material can be reduced. As a result, the chip 123 and the chip holder 22 can be prevented from being damaged.

  Further, according to the present embodiment, the one side edge 175 in the thickness direction of the portion 174 between the cutting edges extends in the other direction A2 in the thickness direction as it extends toward the other B2 in the longitudinal direction. Accordingly, the dimension difference T4 in the thickness direction A between the longitudinal direction other B2 side end portion 179 of the portion 173 between the cutting edges and the longitudinal direction one B1 side end portions 171a and 172a of the divided cutting blade portion adjacent to the longitudinal direction one B1 thereto. , T5 can be increased. The step in the thickness direction A between the cutting edge portion 174 and the cutting edge portion 173 formed in this way works as a chip breaker for subdividing the chips, and the chips are subdivided to improve the chip dischargeability. This can be further improved.

  FIG. 5 is a side view showing a throw-away tip 223 according to the third embodiment of the present invention. The throw-away tip 223 of the third embodiment has a configuration similar to that of the throw-away tip 23 of the first embodiment. Similar parts are denoted by reference numerals obtained by adding 200 to the reference numerals of the configuration of the first embodiment, and description thereof is omitted.

  The chip 223 has a different configuration of the side surface portion 291 compared to the chip 23 of the first embodiment, and the rest is the same. Specifically, in the chip 223, the first cutting edge 230 is formed at the intersecting ridge line portion between the upper surface portion 290 that is the one side A1 side in the thickness direction and the side surface portion 291 that is bent in the thickness direction A from the upper surface portion 290. . The side surface portion 291 is formed with a groove 292 that extends in the width direction C and extends in the thickness direction A from the surface of the side surface portion. The groove 292 is formed from the one surface in the thickness direction of the side surface portion 291 to the other surface in the thickness direction. The first cutting edge 230 has a plurality of divided cutting edges 270, 271, and 272 that are divided in the longitudinal direction B by the grooves 292.

  In the present embodiment, the chip 223 is formed to be 180 degrees rotationally symmetric, so as shown in FIG. 5, the groove 292 and the divided cutting blades 270 to 272 have a width direction C of the chip 223 across the reference axis L2. Formed on both sides. Hereinafter, the groove 292 and the divided cutting edges 270 to 272 on the one side C1 side in the width direction will be described, and the description of the groove 292 and the divided cutting edges 270 to 272 on the other side C2 side in the width direction will be omitted.

  One or more grooves 292 are formed, and in this embodiment, two grooves 292 are formed in the side surface portion 291. The depth C in the width direction of the groove 292 is set deeper than the maximum feed amount per blade of the end mill 20. The groove 292 extends along the circumferential direction around the axis of the chip holder. Each of the divided cutting blades 270 to 272 is inclined in the thickness direction other side A <b> 2, that is, in the direction approaching the bottom surface 186 as it goes to the other longitudinal direction B <b> 2.

  As shown in FIG. 5, when the side surface is viewed from the width direction C, the tip 223 is between the divided cutting blade portions 273 forming the divided cutting blades 270 to 272 and the cutting blades between the divided cutting blades. A portion 274 is formed. The divided cutting blades 270 to 272 serving as the side edges on the one A1 side in the thickness direction of the divided cutting blade portions 273 respectively extend in parallel. In addition, the thickness direction dimensions T1, T2, and T3 of the end portions 270a, 271a, and 272a in the longitudinal direction of the divided cutting blades 270 to 272 and the bottom surface 286 are uniformly formed. In addition, the thickness direction one A1 edge 275 of the portion 274 between the cutting edges that is between the two divided cutting edges arranged in the longitudinal direction B is inclined and extends in the thickness direction one A1 toward the other longitudinal direction B2. Of the portions 274 between the cutting edges, the one side in the longitudinal direction B1 side retreats in the thickness direction A more than the part in the longitudinal direction other B2 side of the divided cutting blades in the longitudinal direction one B1. Moreover, the other longitudinal direction B2 side part of each edge part 274 retracts | saves in the thickness direction A rather than the longitudinal direction one B1 side part of the division | segmentation cutting blade of longitudinal direction other B2.

  According to the third embodiment of the present invention as described above, the same effects as those of the first embodiment can be obtained. Moreover, in 3rd Embodiment, each division | segmentation cutting blade 270-272 extends in parallel with each other, and thickness direction dimension T1, T2 of the longitudinal direction one B1 side edge part 270a-272a and bottom face 286 of each division | segmentation cutting blade 270-272. , T3 are formed uniformly. Thus, at the initial stage where the tip 223 contacts the work material, the longitudinal direction one B1 side end portions 270a to 272a of the divided cutting blades 270 to 272 respectively contact the work material in order from the longitudinal direction one B1 side. . Therefore, the force applied to the chip 223 and the chip holder 22 from the work material can be prevented from being extremely biased, and stress can be prevented from concentrating on a part of the chip 223 and the chip holder 22. Thereby, damage to the chip 23 and the chip holder 22 can be prevented. In addition, in each of the divided cutting blades 270 to 272, the thickness direction dimensions T1, T2, and T3 between the B1 side portion in the longitudinal direction and the bottom surface 86 can be increased as compared with the first embodiment. By increasing the rigidity, damage to the chip 223 can be prevented. In addition, since each of the divided cutting blades 170 to 172 is inclined with respect to the bottom surface 186, compared to a case where the plurality of divided cutting blades extend parallel to the bottom surface at the initial stage where the chip 223 contacts the work material, The impact when the tip 223 collides with the work material can be reduced. Thereby, damage to the chip 223 and the chip holder 22 can be prevented.

  Moreover, according to this embodiment, the thickness direction one side surface of the part 274 between the cutting blades inclines and extends in one thickness direction A1 as it goes to the other longitudinal direction B2. As a result, the rigidity of the chip 223 can be further increased, and damage to the chip 223 can be prevented. Moreover, the chip | tip discharged | emitted is prevented from inhibiting the movement of a chip | tip, and the chip | tip discharge | emission property of the chip | tip 223 is further improved because the chip | tip discharged | emitted moves along the thickness direction one side A1 side surface of the part 274 between cutting edges. be able to.

  FIG. 8A is a side view showing a throw-away tip 323 according to the fourth embodiment of the present invention. The throw-away tip 323 of the fourth embodiment has a configuration similar to that of the throw-away tip 23 of the first embodiment. Similar parts are denoted by reference numerals obtained by adding 300 to the reference numerals of the configuration of the first embodiment, and description thereof is omitted.

  The chip 323 is different in the configuration of the side surface portion 391 from the chip 23 of the first embodiment, and the rest is the same. Specifically, in the chip 323, the first cutting edge 330 is formed at the intersecting ridge line portion between the upper surface portion 390 that becomes the one A1 side portion in the thickness direction and the side surface portion 391 that is bent in the thickness direction A from the upper surface portion 390. . The side surface portion 391 is formed with a groove 392 that extends in the width direction C and extends in the thickness direction A from the surface of the side surface portion. The groove 392 has one end on the surface on the one A1 side in the thickness direction of the side surface portion 391 and the other end on the side surface portion 391. The first cutting edge 330 has a plurality of divided cutting edges 370, 371, 372, 372 ′ that are divided in the longitudinal direction B by the grooves 392.

  One or more grooves 392 are formed. In the present embodiment, three grooves 392 are formed in the side surface portion 391. The depth C in the width direction of the groove 392 is set deeper than the maximum feed amount per blade of the end mill 20. The groove 392 extends along the circumferential direction around the axis of the chip holder. Further, the groove 392 has one end on the surface on the one A1 side in the thickness direction of the side surface portion 391 and the other end on the side surface portion 391. Each of the divided cutting blades 370 to 372 ′ is inclined in the thickness direction other side A <b> 2, that is, in a direction approaching the bottom surface 386, toward the other longitudinal direction B <b> 2.

  When the side surface is viewed from the width direction C as shown in FIG. 8 (a), the tip 323 includes the divided cutting blade portions 373 that form the divided cutting blades 370 to 372 ′, and the space between the divided cutting blades. A cutting edge portion 374 is formed. Each divided cutting edge portion 373 is formed by being connected on the other side A2 in the thickness direction. That is, each inter-cutting-blade portion 374 does not reach the bottom surface 386 and is formed to have a thickness direction one A1 side surface 375 and a thickness direction other A2 side surface 376.

  According to the fourth embodiment of the present invention as described above, the same effects as in the first embodiment can be obtained. Moreover, in 4th Embodiment, each division | segmentation cutting-blade part 373 is connected and formed in the thickness direction other A2 side. Thereby, the rigidity of the entire chip 323 can be increased. That is, it is possible to increase the rigidity of the divided cutting blade portion 373 that forms the divided cutting blade 370 that first contacts the work material in the tip 323. Therefore, the chip 323 can be prevented from being damaged and can be used for more severe heavy cutting.

  The groove 392 is formed so that the other end does not reach the bottom surface portion 386. Thereby, the rigidity of the chip 323 can be increased. Furthermore, since the bottom surface portion 386 is formed large, the chip 323 can be more stably attached to the chip holder.

  FIGS. 8B and 8C illustrate first and second cutting edge modifications 323 ′ and 323 ″ of the chip 323 according to the fourth embodiment. FIGS. 8B and 8C. As described above, the first blades 330 are not on one imaginary straight line, and the respective divided cutting blades may not be parallel.Specifically, in the chip 323 ′ shown in FIG. Among them, the divided cutting blade 370 is configured by a curved cutting blade extending in a tangential direction with respect to a straight line parallel to the bottom surface 386. Further, the divided cutting blade 372 ′ is also configured by a curved cutting blade. Any of the divided cutting blades is inclined in a direction approaching the bottom surface 386 toward the other side B2 in the longitudinal direction. Further, in the chip 323 ″ shown in FIG. 8 (c), in the divided cutting blades 370 to 372 ′, the groove 392 is formed. The divided cutting blades 371 and 372 sandwiched are formed by curved cutting blades. Further, the divided cutting blades 370 and 372 ′ positioned on both end sides of the first blade 330 are configured by linear cutting blades on one side in the longitudinal direction B <b> 1 or the other side in the longitudinal direction B <b> 2. In particular, the divided cutting blade 370 is configured by a linear cutting blade whose longitudinal direction B1 side is parallel to the bottom surface 386.

  According to the first and second cutting edge modifications 323 ′ and 323 ″ of the tip 323 according to the fourth embodiment of the present invention as described above, the division that first contacts the work material during cutting and is subjected to the largest load is performed. The strength of the cutting edge 370 can be further increased, whereby the cutting edge can be further prevented from being damaged.

  FIG. 9 is a side view showing a throw-away tip 423 according to the fifth embodiment of the present invention. The throw-away tip 423 of the fifth embodiment has a configuration similar to that of the throw-away tip 23 of the first embodiment. Similar parts are denoted by reference numerals obtained by adding 400 to the reference numerals of the configuration of the first embodiment, and description thereof is omitted.

  The chip 423 has a different configuration of the side surface portion 491 compared to the chip 23 of the first embodiment, and the rest is the same. Specifically, in the chip 423, the first cutting edge 430 is formed at the intersecting ridge line portion between the upper surface portion 490 that is the one side A1 side in the thickness direction and the side surface portion 491 that is bent in the thickness direction A from the upper surface portion 490. . The side surface portion 491 is formed with a groove 492 that extends in the width direction C and extends in the thickness direction A from the surface of the side surface portion. The groove 492 is formed from the thickness direction one A1 side surface of the side surface portion 491 to the thickness direction other A2 side surface. The first cutting edge 430 has a plurality of divided cutting edges 470, 471, 472 that are divided in the longitudinal direction B by the grooves 492.

  One or more grooves 492 are formed. In this embodiment, two grooves 492 are formed in the side surface portion 491. The depth C in the width direction of the groove 492 is set deeper than the maximum feed amount per blade of the end mill 20. The groove 492 extends along the circumferential direction around the axis of the chip holder. Further, the groove 492 is formed to be biased toward the longitudinal direction A1 side of the side surface portion 491. Therefore, the divided cutting blade 472 is formed to be particularly long compared to the other divided cutting blades 470 and 471. Each of the divided cutting blades 470 to 472 is inclined in the direction closer to the other side A2 in the thickness direction, that is, the bottom surface 486 toward the other side B2 in the longitudinal direction.

  When the side end face is viewed from the width direction C as shown in FIG. 9, the tip 423 is provided between the divided cutting blade portions 473 forming the respective divided cutting blades 470 to 472 and the cutting blades between the divided cutting blades. A portion 474 is formed. The divided cutting blades 470 to 472 that are the edges on the one A1 side in the thickness direction of the divided cutting blade portions 473 extend in parallel. The divided cutting blade 472 is formed to be particularly longer than the other divided cutting blades 470 and 471. Therefore, the divided cutting edge portion 473 that forms the divided cutting blade 472 is larger than the other divided cutting blade portions 473.

According to the fifth embodiment of the present invention as described above, the same effect as that of the first embodiment can be obtained. In the fifth embodiment, each of the divided cutting blades 470 to 472 extends in parallel with each other, and the divided cutting blades 472 are formed to be particularly longer than the divided cutting blades 470 and 471. That is, no groove 492 is formed on the other side B <b> 2 in the longitudinal direction of the first blade 430. This
The intensity | strength of the longitudinal direction other B2 side part of the 1st blade 430 which the thickness direction dimension becomes small can be enlarged. Therefore, the rigidity of the chip 423 can be increased, and damage to the chip during processing can be prevented.

  FIG. 10 is a side view showing a throw-away tip 523 according to the sixth embodiment of the present invention. The throw-away tip 523 of the sixth embodiment has a configuration similar to that of the throw-away tip 23 of the first embodiment. Similar parts are denoted by reference numerals obtained by adding 500 to the reference numerals of the configuration of the first embodiment, and description thereof is omitted.

  The tip 523 has a different shape between the cutting edges of the side surface portion 591 compared to the tip 423 of the fifth embodiment, and the remaining portion is the same. Specifically, in the chip 523, the first cutting edge 530 is formed at the intersecting ridge line portion between the upper surface portion 590 that is a portion on the one A1 side in the thickness direction and the side surface portion 591 that is bent from the upper surface portion 590 in the thickness direction A. . The side surface 591 is formed with a groove 592 that extends in the width direction C and extends in the thickness direction A from the surface of the side surface. Similar to the chip 323 of the fourth embodiment, the groove 592 is formed with one end reaching the surface in the thickness direction of the side surface portion 591 on the one A1 side and the other end on the side surface portion 591. The first cutting edge 530 has a plurality of divided cutting edges 570, 571, 572 that are divided in the longitudinal direction B by the grooves 592.

  As shown in FIG. 10, the portion 574 between the cutting edges is formed to be biased toward the one side A1 in the longitudinal direction of the side surface portion 591, similarly to the tip 423 of the fifth embodiment, and the tip 323 of the fourth embodiment. Similarly, it is formed having a surface 576 on the other side in the thickness direction.

  According to the sixth embodiment of the present invention as described above, the same effects as those of the first embodiment, the fourth embodiment, and the fifth embodiment can be obtained. That is, since the rigidity of the chip 523 can be increased, chip damage can be suppressed and a long-life chip can be provided even in severer heavy cutting.

  The present embodiment as described above is merely an example of the invention, and the configuration can be changed within the scope of the invention. For example, although the end mill 20 has been described as a turning tool, the same effect can be obtained even with other turning tools that do not have a secondary cutting edge. Moreover, in this Embodiment shown by 1st Embodiment-4th Embodiment (a), although the inclination of each division | segmentation cutting edge extended in parallel, it did not extend mutually parallel like other embodiment. Also good. In the present embodiment, the chip 23 is formed 180 degrees rotationally symmetrical around the reference axis L2, but may not be formed 180 degrees rotationally symmetric.

  FIG. 11A is a plan view and FIG. 11B is a side view showing a throw-away tip 623 according to a seventh embodiment of the present invention. The throw-away tip 623 of the seventh embodiment has a configuration similar to that of the throw-away tip 23 of the first embodiment. Similar parts are denoted by reference numerals obtained by adding 600 to the reference numerals of the configuration of the first embodiment, and description thereof is omitted. As shown in FIG. 11, a direction perpendicular to the thickness direction A and the width direction C is a cutting edge direction D. Hereinafter, in the cutting edge direction D, the cutting edge direction from the other end d2 of the first blade 630 toward the one end d1 is referred to as a cutting edge direction one D1, and the cutting blade from the one end d1 of the first blade 630 toward the other end d2 The direction is the other cutting edge direction D2.

  The chip 623 differs from the chip 23 of the first embodiment in the shape of the chip and the configuration of the side surface portion 691, and the rest is the same. Specifically, the chip 623 is formed in a substantially square plate shape, whereas the chip 23 of the first embodiment is in a substantially parallelogram plate shape. Further, in the chip 623, the first cutting edge 630 is formed at the intersecting ridge line portion between the upper surface portion 690 that is a portion on the one A1 side in the thickness direction and the side surface portion 691 that is bent in the thickness direction A from the upper surface portion 690. The side surface 691 is formed with a groove 692 that extends in the width direction C and extends in the thickness direction A from the surface of the side surface. The groove 692 is formed with one end on the surface on the one A1 side in the thickness direction of the side surface portion 691 and the other end on the side surface portion 691. The first cutting edge 630 has a plurality of divided cutting edges 670, 671, 672, 672 ′ that are divided in the cutting edge direction D by the grooves 692.

  One or more grooves 692 are formed, and in this embodiment, three grooves 692 are formed in the side surface portion 691. The depth C in the width direction of the groove 692 is set deeper than the maximum feed amount per blade of the end mill 20. The groove 692 extends along the circumferential direction around the axis of the chip holder. Further, like the chip 323 of the fourth embodiment, the groove 692 is formed with one end on the one surface in the thickness direction of the side surface portion 691 and the other end on the side surface portion 691. Of each of the divided cutting blades 670 to 672 ′, the divided cutting blades 671 and 672 sandwiched between the grooves 692 are inclined in the thickness direction other side A2, that is, in the direction approaching the bottom surface 686, respectively, toward the other cutting edge direction D2. . Further, the divided cutting blade 670 having one end d1 of the first blade 630 is inclined so as to move away from the bottom surface 686 from the tip in the cutting blade direction D2 side toward the cutting blade direction D1, and at a certain central portion. Inclined in the opposite direction, ie, closer to the bottom surface 686. Further, the divided cutting blade 672 ′ having the other end d2 of the first blade 630 is once inclined to approach the bottom surface 686 from the tip in the cutting blade direction other D2 side toward the cutting blade direction one D1. The part is inclined in the opposite direction, that is, away from the bottom surface 686.

  As shown in FIG. 11, when the side surface is viewed from the width direction C, the tip 623 is divided between the divided cutting blade portions 673 forming the respective divided cutting blades 670 to 672 ′ and the cutting blades between the divided cutting blades. An intermediate portion 674 is formed. Each divided cutting edge portion 673 is formed by being connected on the other side A2 in the thickness direction. That is, the portion 674 between the cutting edges does not reach the bottom surface 686 and is formed to have one surface A <b> 1 side 675 in the thickness direction and the other surface A <b> 2 side 676 in the thickness direction.

  According to the seventh embodiment of the present invention as described above, the same effects as those of the first embodiment and the fourth embodiment can be obtained. Moreover, in 7th Embodiment, since a chip | tip shape is comprised by substantially square plate shape, a cutting blade can be formed in four places of an intersection ridgeline part. This prolongs the tool life of the insert 623 and makes it economically superior.

  The present embodiment as described above is merely an example of the invention, and the configuration can be changed within the scope of the invention. For example, although the end mill 20 has been described as a turning tool, the same effect can be obtained even with other turning tools that do not have a secondary cutting edge. Further, in the present embodiment, the divided cutting blades positioned at both ends of the first blade are not inclined in one direction to the one formed in a substantially square plate shape, and the inclined direction is different in one divided cutting blade. Although the chip is shown, the divided cutting blades of chips having other shapes such as a substantially parallelogram plate shape may be formed with such a configuration as in other embodiments. In the present embodiment, the chip 23 is formed 180 degrees rotationally symmetrical around the reference axis L2, but may not be formed 180 degrees rotationally symmetric.

It is a perspective view which shows the throw away tip 23 which is the 1st Embodiment of this invention. 4 is a side view showing a throw-away tip 23. FIG. 1 is a perspective view showing an end mill 20 in which a throw-away tip 23 according to a first embodiment of the present invention is attached to a tip holder 22. FIG. It is a side view which shows the throw away tip 123. FIG. It is a side view showing a throwaway tip 223. It is a side view which shows the throwaway tip 1 of a prior art. 1 is a perspective view showing a throw-away tip 1. FIG. It is (a) a side view showing a throwaway tip 323, (b) a first blade modification of the throwaway tip 323, and (c) a second cutting blade modification. It is a side view showing a throwaway tip 423. It is a side view showing a throwaway tip 523. It is (a) top view and (b) side view which show the throw away tip 623.

Explanation of symbols

20 End mill 22 Tip holder 23 Throw-away tip 24 Mounting part 30 First cutting edge 39 Bottom face part 70, 71, 72, 72 'Split cutting edge 86 Bottom face 90 Top face part 91 Side face part 92 Groove A Thickness direction B Longitudinal direction C Width direction D Cutting edge direction

Claims (12)

It has a cutting edge that is formed in a substantially plate shape and extends in a predetermined longitudinal direction at an intersecting ridge line portion between an upper surface portion serving as one side portion in the thickness direction and a side surface portion bent from the upper surface portion to the other in the thickness direction. A throw-away tip that is attached with the bottom surface serving as the side surface in contact with the tip holder,
In the side surface portion, a groove that is immersed from the surface of the side surface portion and extends in the thickness direction is formed,
The cutting blade has a plurality of divided cutting blades that are divided in the longitudinal direction by the grooves, and each of the divided cutting blades is inclined so as to move away from the bottom surface toward one side in the longitudinal direction with respect to the thickness direction. To throw away tip.   The throw-away tip according to claim 1, wherein each of the divided cutting blades is arranged on a predetermined virtual straight line.   The said division | segmentation cutting edge is extended mutually parallel, The thickness direction dimension of the longitudinal direction one side edge part and bottom face of each division | segmentation cutting edge is formed uniformly, respectively. Throw away tip.   The throw portion according to claim 3, wherein the portion between the cutting edges between the two divided cutting blades arranged in the longitudinal direction has a surface on one side in the thickness direction extending along the divided cutting blade adjacent to one side in the longitudinal direction. Away tip.   The portion between the cutting edges between the two divided cutting blades arranged in the longitudinal direction has one surface in the thickness direction progressing in one direction in the thickness direction from the dividing cutting blade adjacent in the longitudinal direction to the other in the longitudinal direction. The throw-away tip according to claim 3. The throw-away tip according to any one of claims 1 to 5,
A cutting tool comprising a tip holder for mounting a plurality of the throwaway tips.   The rolling tool according to claim 6, wherein the groove is formed along a circumferential direction around an axis of the chip holder. The main body portion is formed in a substantially plate shape, and has a predetermined cutting edge at a crossing ridge line portion between an upper surface portion serving as one side portion in the thickness direction and a side surface portion bent from the upper surface portion to the other in the thickness direction. A throw-away tip that is attached by contacting the tip holder with the bottom of the tip,
The side surface portion is formed with a groove that is immersed from the surface of the side surface portion and extends in the thickness direction.
The cutting blade has a plurality of divided cutting blades divided by the groove,
Among the divided cutting blades, the divided cutting blades sandwiched between the grooves are each inclined so as to move away from the bottom surface toward the one end of the cutting blade in the thickness direction.   Among the divided cutting blades, the divided cutting blade having one end of the cutting blade is inclined so as to be once away from the bottom surface toward the one end of the cutting blade, and then inclined so as to approach the bottom surface. The slow way chip according to claim 8. The main body is formed in a substantially square plate shape,
Of the divided cutting blades, the divided cutting blade having the other end of the cutting blade is inclined so as to approach the bottom surface once and toward the one end of the cutting blade, and then inclined so as to move away from the bottom surface. The throw-away tip according to claim 8 or 9. The throw-away tip according to any one of claims 8 to 10,
A cutting tool comprising a tip holder for mounting a plurality of the throwaway tips.   The rolling tool according to claim 11, wherein the groove is formed along a circumferential direction around an axis of the chip holder.

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