WO2015119259A1

WO2015119259A1 - Cutting insert

Info

Publication number: WO2015119259A1
Application number: PCT/JP2015/053432
Authority: WO
Inventors: 岳志山口
Original assignee: 株式会社タンガロイ
Priority date: 2014-02-07
Filing date: 2015-02-06
Publication date: 2015-08-13
Also published as: JP2017064797A

Abstract

A cutting insert (1) according to an embodiment of the present invention is provided with: at least one cutting blade (8) that is formed at the intersection ridge section of a rake face (6) and a flank face (7); and at least one protruding section (12). The cutting blade (8) comprises a cutting blade part that extends along a corner section (5). The protruding section (12) is formed so as to protrude at the rake face (6). The protruding section (12) comprises a width expansion part (13) that gradually becomes wider as proximity to the cutting blade part of the corner section increases.

Description

Cutting insert

The present invention relates to a cutting insert that is attached to a tool body of a cutting tool so as to be freely attached and used for cutting a metal material or the like.

Conventional cutting inserts include those shown in Patent Document 1. The cutting insert of patent document 1 is a polygonal plate-shaped cutting insert, and the chip breaker groove is formed in each of two opposing end surfaces. The chip breaker groove is formed at a position including the vicinity of the corner portion of each end face. The chip breaker groove includes a rake face. A side surface connecting the two end surfaces is a flank. A cutting edge is formed at the intersection ridge line portion between the rake face and the flank face. The cutting insert of patent document 1 further has a breaker protrusion part. The breaker projections are formed to protrude integrally from the chip breaker groove so as to spread symmetrically with respect to the bisector of the corner portion from the corner portion toward the center of the mounting hole. And in the cutting insert of patent document 1, the chip which flows along the rake face which makes an acute angle with respect to a side surface is made to collide with a breaker projection part, and is divided.

Japanese Utility Model Publication No. 2-4702

The conventional cutting insert of Patent Document 1 is directed to cutting a chip flowing along a rake face with a breaker protrusion located at a position farther from the cutting edge than the rake face. There is room for improvement. Specifically, the cutting insert of Patent Document 1 has a smooth rake face along the cutting edge, and crater wear tends to occur on the rake face. Occurrence of crater wear causes chipping and chipping of the cutting edge, and causes a reduction in tool life.

An object of the present invention is to provide a cutting insert capable of suppressing the occurrence of crater wear without impairing chip disposal.

According to one aspect of the invention,
A cutting insert,
At least one cutting edge formed at the intersection ridge line portion of the rake face and the flank face, each cutting edge including a cutting edge portion extending along the corner portion;
At least one raised portion formed to rise on the rake face;
The raised portion has a width-enlarging portion that gradually increases as the cutting edge portion is approached.
A cutting insert is provided.

According to the cutting insert of the above aspect having such a configuration, the chip at the time of cutting can be forcibly separated from the rake face by the raised portion. For this reason, generation | occurrence | production of the crater wear in a rake face can be suppressed significantly. Further, the raised portion is formed with respect to the rake face and does not impair the degree of freedom in forming the breaker wall surface. Therefore, according to the cutting insert of the said one aspect | mode of this invention, generation | occurrence | production of crater wear can be suppressed without impairing chip disposal, and tool life can be extended significantly.

The cutting insert has two opposing end faces, and a first end face of the two end faces is substantially polygonal when viewed from the side facing the first end face. An end surface and a peripheral side surface formed between the two end surfaces facing each other, wherein the cutting edge intersects the rake surface of the first end surface and the clearance surface of the peripheral side surface It can be formed on the ridge line portion.

Preferably, the raised portion is formed inside the corner portion and extends in a direction intersecting with the corner portion. In addition, a chip breaker groove including the rake face and the rising wall surface may be formed on the first end face. In this case, the raised portion may cross a bottom portion between the cutting edge and the rising wall surface. Further, the chip breaker groove may have a breaker projection protruding inwardly. In this case, the breaker protrusion may be connected to the raised portion.

Further preferably, the cutting insert according to an embodiment of the present invention may further include at least one ridge formed so as to protrude from the rake face. The ridge may extend while curving in a direction away from the associated corner. When the cutting insert is viewed from the side facing the first end surface, the raised portion has a portion extending from the width-enlarged portion so as to extend along a bisector of the corner portion, and the ridge is It is good to extend so that it may be substantially circular arc shape and this protruding part may be pinched | interposed.

Preferably, the width-enlarged portion of the raised portion is inclined so as to gradually approach the second end surface of the two end surfaces as the distance from the cutting edge increases. More preferably, when a land is formed between the cutting edge portion and the width-enlarged portion in the corner portion, the slope of the width-enlarged portion in the sectional shape in the bisector direction at the corner portion Is preferably smaller than the rake angle of the land. In addition, the edge part by the side of the said cutting blade with which the said width expansion part is related can be comprised as a plane substantially parallel to each of the said two end surfaces.

The first end face may include one or more cutting edges. When a plurality of cutting edges are formed at the intersecting ridge line portion between the first end surface and the peripheral side surface, the first end surface is configured to be rotationally symmetrical n times around the first axis (where n is a natural number of 2 or more). Can do. When a plurality of cutting edges are formed at the intersecting ridge line portion between the second end surface and the peripheral side surface, the second end surface is formed around the second axis defined to be orthogonal to the first axis. It can be configured to be 180 ° rotationally symmetric with the end face. In addition, although the some cutting edge in a 1st end surface may have the same structure (or the same shape), it is not limited to it, You may provide two or more types of cutting edges which have a different shape. Preferably, the end portion on the side of the cutting edge related to the width-enlarging portion of the raised portion may extend along an imaginary plane defined to be orthogonal to the first axis.

FIG. 1 is a perspective view of a cutting insert according to the first embodiment of the present invention. FIG. 2 is an enlarged perspective view of the vicinity of a corner portion of the cutting insert shown in FIG. FIG. 3 is a plan view of the cutting insert shown in FIG. FIG. 4 is a side view of the cutting insert shown in FIG. 5A is a schematic cross-sectional view of a part of the cutting insert of FIG. 1 taken along the line VA-VA in FIG. 5B is a schematic cross-sectional view of a part of the cutting insert of FIG. 1 taken along the line VB-VB in FIG. 6 is a schematic cross-sectional view for explaining a modification of the cutting insert of FIG. 1, and is a view at a position corresponding to the VA-VA cross-sectional line in FIG. FIG. 7 is a perspective view of a cutting insert according to the second embodiment of the present invention. FIG. 8 is a plan view of the cutting insert shown in FIG. 9 is a schematic cross-sectional view of a part of the cutting insert of FIG. 7 taken along the line IX-IX in FIG. FIG. 10 is a perspective view of a cutting insert according to the third embodiment of the present invention. FIG. 11A is a plan view of the cutting insert of FIG. FIG. 11B is a plan view of a portion near one corner portion of the cutting insert of FIG. 12A is a schematic cross-sectional view of a part of the cutting insert of FIG. 10 taken along the XIIA-XIIA cross-sectional line in FIG. 11A. FIG. 12B is a schematic cross-sectional view of a part of the cutting insert of FIG. 10 taken along the line XIIB-XIIB in FIG. 11A. FIG. 13 is a perspective view of a cutting insert according to the fourth embodiment of the present invention. 14A is a plan view of the cutting insert of FIG. 14B is a plan view of a portion in the vicinity of one corner portion of the cutting insert of FIG. 15 is a schematic cross-sectional view of a part of the cutting insert of FIG. 13 taken along the line XV-XV in FIG. 14A. FIG. 16 is a view for explaining an example of use of the cutting insert of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First, the cutting insert 1 according to the first embodiment of the present invention will be described.

As shown in FIGS. 1 and 3, the cutting insert 1 of this embodiment has a substantially rhomboid plate shape. The cutting insert 1 has two substantially rhombic end faces 2 and 3 that face each other, and a peripheral side face 4 that connects the two end faces 2 and 3. Each end face of the approximately rhombus has four corners or corner portions 5, more specifically, two corner portions (first corner portions) 5a having an internal angle of 80 ° in plan view of FIG. 3, and FIG. And two corner portions (second corner portions) 5b having an internal angle of 100 ° in plan view. Here, the end surface (first end surface) 2 shown in FIG. 1 is referred to as an upper surface, and the other end surface (second end surface) 3 of the two

end surfaces

2 and 3 is referred to as a lower surface. To make the explanation easier to understand, terms such as “upper surface” that indicate the orientation in the space are used. However, this is for convenience, and the absolute orientation and positional relationship in the space should be specified. Is not intended. Unless otherwise noted, the same applies to terms representing orientations and positional relationships in other spaces.

As described above, the upper surface 2 has a substantially rhombus when the cutting insert 1 is viewed from the side facing the upper surface 2, that is, in a plan view of FIG. Accordingly, the upper surface 2 has two sets of opposing side portions, more specifically, a set of opposing first

upper side portions

2a and 2a, and a set of opposing second

upper side portions

2b and 2b. Have Similarly, the lower surface 3 has a substantially rhombus shape and has a pair of first

lower side portions

3a and 3a facing each other and a pair of second

lower side portions

3b and 3b facing each other. A first side surface 4a extends between the first upper side 2a and the first lower side 3a, and a second side 4b extends between the second upper side 2b and the second lower side 3b. A first corner side surface 4c that connects the first corner portion 5a of the upper surface 2 and the first corner portion 5a of the lower surface 3 is formed so as to connect the first and second side surfaces 4a and 4b. A second corner side surface 4d that connects the two corner portions 5b and the second corner portion 5b of the lower surface 3 is formed.

Each of the end faces 2 and 3 of the cutting insert 1 is formed to be 180 ° rotationally symmetric. The cutting insert 1 has a mounting hole 1 a that extends so as to penetrate the upper surface 2 and the lower surface 3. The cutting insert 1 is 180 ° rotationally symmetric (that is, twice rotationally symmetric) around the central axis (first axis) 1b of the mounting hole 1a.

The cutting insert 1 of this embodiment is a so-called negative type cutting insert 1 that can be used on both sides by turning the upper surface 2 and the lower surface 3 upside down. In addition, when an axis (second axis) 1c perpendicular to the central axis 1b of the mounting hole 1a and penetrating the peripheral side surface 4 is determined as shown in FIG. 3, it is 180 ° rotationally symmetric about the second axis 1c. Moreover, the cutting insert 1 is formed. Therefore, the first and second

upper side portions

2a and 2b have the same shape and configuration as the second and first

lower side portions

3b and 3a, respectively, and the lower surface 3 has the same shape and the same configuration as the upper surface 2. Therefore, a plan view (not shown) of the cutting insert 1 when viewed from the side facing the lower surface 3 corresponds to FIG. In other words, the lower surface side has the same configuration relating to the cutting blade on the upper surface side. The cutting edge 8 is formed at the intersection ridge line portion between the upper surface 2 and the peripheral side surface 4, and is also formed at the intersection ridge line portion between the lower surface 3 and the peripheral side surface 4. Each cutting edge 8 is formed at an intersection (intersecting ridgeline) between the rake face 6 and the flank face 7. The rake face 6 extends to a corresponding end face on which a corresponding cutting edge 8 is formed at the edge. The flank 7 extends to the peripheral side 4. A chip breaker groove 11 is formed on each of the upper and

lower surfaces

2 and 3 corresponding to each cutting edge 8. The chip breaker groove 11 on the upper surface 2 has the same shape and the same configuration as the chip breaker groove 11 on the lower surface 3. Hereinafter, since the lower surface 3 has the same configuration as the upper surface 2 as described above, the upper surface 2 will be described, and the description regarding the lower surface 3 will be omitted. However, it should be noted that the description relating to the upper surface 2 applies to the lower surface 3 as well. In addition, this invention accept | permits the cutting insert which has a cutting edge only on one side, and the various cutting insert which has only one or several cutting edge.

A chip breaker groove 11 is formed with respect to the cutting edge 8. Here, the inclined surface that generally descends from the cutting edge 8 to the bottom of the chip breaker groove 11 is referred to as a rake face 6. In exceptional cases, the rake face 6 includes a case where the rake angle is 0 ° (when the rake face extends along a virtual plane defined to be orthogonal to the central axis 1b). That is, the rake face may not fall from the cutting edge 8. In addition, honing or the like is applied to the cutting edge 8 so that the rake face 6 may include a surface portion that is locally inclined reversely (contributes to the formation of a negative rake angle). The rake face 6 may be provided with a land 17 or the like, and may include a surface portion that is locally inclined reversely.

The portion of the peripheral side surface 4 connected to the cutting edge 8 is a flank 7. The flank 7 intersects the upper surface 2 and the lower surface 3 at right angles, and the cutting insert 1 is a cutting insert having a flank angle of 0 °. More precisely, when a virtual plane perpendicular to the central axis (first axis) 1b of the mounting hole 1a is defined, the peripheral side surface 4, that is, the flank 7 extends at right angles to the virtual plane.

With respect to the upper surface 2, two first cutting edges 8 a provided with respect to the first corner portion 5 a having an internal angle of 80 ° in a plan view (that is, FIG. 3), and a second corner portion 5 b having an internal angle of 100 ° in a plan view. Are formed with two second cutting edges 8b. Since the inner angle of the corner portion is different, the first cutting edge 8a has a different shape from the second cutting edge 8b, but has the same configuration.

Each of the cutting edges 8 (8a, 8b) is configured as one cutting edge section, and includes at least two cutting edge portions, that is, a cutting edge portion of the corner portion and a cutting edge portion connected to the cutting edge portion of the corner portion. And have. Specifically, the first cutting edge 8a includes a corner cutting edge 9a having a substantially arc shape provided in the first corner portion 5a, and a pair of

linear cutting edges

10a, 10b respectively extending from the corner cutting edge 9a. Consists of. The second cutting edge 8b includes a corner cutting edge 9b provided in the second corner portion 5b and a pair of

linear cutting edges

10c and 10d extending from the corner cutting edge 9b. The

corner cutting edges

9a and 9b have shapes corresponding to the curved shapes of the

corresponding corner portions

5a and 5b, respectively. Regarding the first cutting edge 8a, the linear cutting edge 10a is connected to one end of the corner cutting edge 9a, extends toward the second corner part 5b along the first side part 2a of the upper surface 2, and is linear. The cutting edge 10b is connected to the other end of the corner cutting edge 9a and extends toward the second corner portion 5b along the second side portion 2b of the upper surface 2. As for the second cutting edge 8b, the linear cutting edge 10c is connected to one end of the corner cutting edge 9b and extends toward the first corner part 5a along the second side part 2b of the upper surface 2. The linear cutting edge 10d is connected to the other end of the corner cutting edge 9b and extends toward the first corner portion 5a along the first side 2a of the upper surface 2. However, since the upper surface 2 of the cutting insert 1 is substantially diamond-shaped as described above, the

linear cutting edges

10a and 10b correspond to the bisector (VA-VA line) of the first corner portion 5a in FIG. ). The

straight cutting edges

10c and 10d are also formed symmetrically with respect to the bisector of the second corner portion 5b in FIG. In the cutting insert 1, the first cutting edge 8a is continuous with the second cutting edges 8b on both sides. Therefore, the cutting insert 1 has the cutting edge 8 over the entire circumference of the upper surface 2. However, the first cutting edge 8a may not be continuous with the second cutting edge 8b.

The material of the cutting edge 8 of the cutting insert 1 is selected from hard materials such as cemented carbide, cermet, ceramic and cubic boron nitride, or those obtained by coating the surface of these hard materials with a PVD or CVD coating film. Further, the material other than the cutting edge 8 is preferably made of the same hard material.

Here, the first cutting edge 8a will be described. A chip breaker groove 11 (11a) is formed in the first cutting edge 8a. The chip breaker groove 11a is formed at least in the vicinity of the first corner portion 5a. In the cutting insert 1, the chip breaker groove 11a is formed along the first cutting edge 8a. The chip breaker groove 11a has a rake face 6, a bottom part 11s, and a rising wall surface (or breaker wall surface) 11r in order from the first cutting edge 8a side, and is defined by these.

The chip breaker groove 11 has a hill or a raised portion 12. The raised portion 12 is connected to the rake face 6 so as to form a raised portion in the rake face 6 extending from the corner portion 5, and forms a part of the rake face. That is, the raised portion 12 is formed so as to rise from the rake face 6 of the corner portion 5. The raised portion 12 is formed inside the first corner portion 5a, and is formed to extend in a direction intersecting with the first corner portion 5a. When proceeding from the corner cutting edge 9a of the first corner portion 5a to the center portion of the upper surface 2 (that is, the mounting hole 1a) along the rake face 6, the top of the raised portion 12 passes from the middle of the rake face 6 through the rake face 6. The raised portion 12 is formed so as to transition to a surface (a portion functioning as a rake surface) without a step. The raised portion 12 is formed so that the inclination angle of the rake face 6 with respect to a virtual plane orthogonal to the central axis 1b is changed relatively small in the middle. Further, in the cutting insert 1, the raised portion 12 extends in a direction perpendicular to the first corner portion 5a in the plan view of FIG. 3, and more specifically, extends along a bisector of the first corner portion 5a. . The raised portion 12 crosses the bottom portion 11s between the rake face 6 and the rising wall surface 11r.

Here, FIG. 5A shows a partial cross section of the cutting insert 1 along the bisector (that is, the VA-VA line) of the first corner portion 5a in FIG. This is schematically shown while changing the ratio. In FIG. 5A, the cross-sectional shape of the portion along the line α-α in FIG. Note that the cross section of the portion along the α-α line cannot be exactly superimposed on the cross section along the VA-VA line from the dimension surface, but it makes it easy to understand the shape and configuration of the raised portion 12. For this purpose, the dimensions and the like are schematically shown in FIG. 5A. Further, FIG. 5B shows a cross section of a part of the cutting insert 1 along a VB-VB line extending in a direction perpendicular to the bisector of the first corner portion 5a in FIG. From FIG. 5A and FIG. 5B, it can be seen that the raised portion 12 is formed so as to rise at the rake face 6 and extends across the bottom of the chip breaker groove 11a. Furthermore, it can be understood that the raised portion 12 is inclined downward, that is, from the upper surface side to the lower surface side, as the rake surface is separated from the cutting edge, so as to form a part of the rake surface 6.

The raised portion 12 extends in a direction (longitudinal direction) intersecting the corner portion, is elongated, and is shaped so that a cross section in a direction orthogonal to the longitudinal direction is substantially trapezoidal. Further, the raised portion 12 is formed so that the length (width) in the short direction, which is the direction orthogonal to the longitudinal direction, changes. The raised portion 12 has a portion of the first cutting edge 8a of the first corner portion 5a in the vicinity that becomes gradually wider as it approaches the corner cutting edge 9a. That is, the raised portion 12 has a width enlarged portion 13. When the raised portion 12 has such a shape, chips that scrape the rake face 6 during the cutting process by the first cutting edge 8a, in particular, the corner cutting edge 9a, are more accurately lifted by the raised portion 12. And is forcibly pulled away from the rake face 6. For this reason, the occurrence of crater wear on the rake face 6 (and the progress thereof) is suppressed. This can extend the tool life. In the cutting insert 1, since the raised part 12 has the width expansion part 13 in the position of the most cutting edge side, the effect can be heightened further. Further, since the raised portion 12 has a substantially trapezoidal cross section in the width direction, the width gradually decreases as the distance from the rake face 6 increases in the direction of the central axis 1b. Therefore, the chips are easily separated from the raised portions 12 as they are separated from the cutting edges, and are consequently forcibly separated from the raised portions 12. Therefore, wear of the raised portion 12 is also suppressed. In addition, what is necessary is just to expand the width expansion part 13 of the protruding part 12 as mentioned above about the whole outer width. Therefore, for example, the raised portion 12 may be formed like a Y shape in which the distal end side of the raised portion 12, that is, the corner portion side branches. When formed in this way, even if the total width of the respective widths of the branch portions does not change, or conversely decreases toward the corner portion side, the width enlarged portion 13 has an overall outer width closer to the corner portion side. What is necessary is just to form so that it may become large. As crater wear progresses, the substantial rake angle increases and the periphery of the cutting edge tends to chip. Or if crater wear progresses, a chip shape will change and chip processing property will be impaired. Especially when the cutting conditions are high, especially when the feed is large, the tool life tends to be early due to the progress of crater wear. Therefore, the tool life can be greatly extended by suppressing the crater wear by forming the raised portion 12 on the rake face.

As shown in FIG. 5A, the width-enlarging portion 13 of the raised portion 12 is inclined so as to gradually decrease as the distance from the cutting edge 8 increases. That is, the widened portion 13 on the upper surface 2 is inclined so as to gradually approach the lower surface 3 as the distance from the cutting edge 8 increases. In this embodiment, the top portion (here, the end portion on the cutting edge side) 14 of the width enlarged portion 13 is an inclined plane. As shown in the schematic cross-sectional view of FIG. 5A along the line VA-VA of FIG. 3, the inclination angle θ2 of the width enlarged portion 13 extends between the width enlarged portion 13 of the raised portion 12 and the first cutting edge 8a. The rake angle θ1 of the portion of the existing rake face 6 is made smaller. That is, as described above, the raised portion 12 is raised from the rake face 6. The reason why FIG. 5A is shown in a schematic view is that the angle difference (= | θ1−θ2 |) of the shape of the actual sectional view in the cutting insert 1 of this embodiment is small and difficult to understand. FIG. 5A is a schematic diagram in which the angle difference and length of each part are emphasized for easy understanding. The angle difference between the inclination angle θ2 and the rake angle θ1 is preferably in the range of 1 ° or more and 30 ° or less. With such an angle difference, the raised portion 12 ensures that chips are pulled away from the rake face 6 and crater wear on the rake face 6 is suppressed. As an exception, the top surface of the top portion 14 of the width-enlarged portion 13 is determined to be a plane substantially parallel to the upper and lower surfaces 2 and 3 (that is, to be orthogonal to the central axis 1b) as shown in FIG. May extend along a virtual plane). That is, the top portion 14 may be formed to have a flat surface that does not incline. The top portion 14 may partially include a portion that is inclined so as to rise as the distance from the cutting edge 8 increases. However, first, it is preferable that the widened portion 13 is inclined so as to gradually decrease as the distance from the cutting edge 8 increases. Next, the top surface 14 of the widened portion 13 is preferably a plane parallel to the lower surface 3. That is, the inclination angle θ2 of the widened portion 13 is preferably in the range of 0 ° to 20 °. In the cutting insert 1 of this embodiment, the rake angle θ1 is about 12 °. The inclination angle θ2 of the widened portion 13 is about 10 °. That is, the angle difference between them is about 2 °. The angles θ1 and θ2 are each orthogonal to the central axis 1b (preferably further through the cutting edge 8) on a plane parallel to the central axis 1b of the mounting hole 1a and orthogonal to the cutting edge (for example, FIG. 5A). It is determined with respect to the virtual plane P determined as follows.

The rake face 6 of the cutting insert 1 of this embodiment has a two-stage structure. That is, the rake face 6 has a first rake face 6a and a second rake face 6b. The one close to the cutting edge 8 is called the first rake face 6a. The first rake face 6 a is also called a land 17. In the cutting insert 1 of this embodiment, the aforementioned rake angle θ1 is the rake angle θ1 of the first rake face 6a, that is, the land inclination angle θ1. However, it is not limited to this. In the cutting insert 1, the raised portion 12 is provided so as to be connected to the first rake face 6a toward the cutting edge, but may be provided so as to be connected to the second rake face 6b. In this case, the rake angle θ1 is the rake angle θ1 of the second rake face 6b. And the inclination | tilt angle (theta) 2 of the width expansion part 13 should just be made smaller than the rake angle (theta) 1 of the 2nd rake face 6b. In that case, the inclination angle θ2 of the widened portion 13 may be made larger than the inclination angle of the land. Of course, the inclination angle of the land may be 0 °. As an exception, the land inclination angle may be a negative angle. When the inclination angle of the land is a negative angle, the raised portion 12 is preferably connected to the second rake face toward the cutting edge.

In the central part of the upper surface 2 and the lower surface 3, a seating surface when mounted on the cutting tool is formed. That is, the chip breaker groove 11 is given a finite width. The seating surface may be referred to as the boss surface 16. The raised portion 12 of the cutting insert 1 of this embodiment is connected to the rising wall surface 11r of the chip breaker groove 11 rising toward the boss surface 16 in a direction away from the cutting edge. The raised portion 12 intersects the rising wall surface 11 r of the chip breaker groove 11. However, it is not limited to this. The raised portion 12 may be smoothly connected to the rising wall surface 11r of the chip breaker groove 11. The boss surface 16 as a seating surface is made higher than the cutting edge 8 in the cutting insert 1 as shown in FIG. 4, but is not limited to being made higher than the cutting edge 8. The seating surface may have any shape as long as the seating surface can be brought into contact with the insert seat of the cutting tool when mounted on the cutting tool. In the cutting insert 1, the boss surface 16 that is a seating surface extends along a virtual plane that is determined to be orthogonal to the central axis 1b.

As for the second cutting edge 8b, the chip breaker groove 11 is formed and the raised portion 12 is formed as described with respect to the first cutting edge 8a. The configuration around the second cutting edge 8b is different from the configuration around the first cutting edge 8a in terms of dimensions such as a raised portion. However, in other aspects, since the configuration around the second cutting edge is the same as the configuration around the first cutting edge, further description regarding the second cutting edge is omitted.

Next, the cutting insert 101 which concerns on 2nd Embodiment of this invention is demonstrated based on FIGS. In order to simplify the description, the same component numbers are assigned to the same components as those of the cutting insert 1 of the first embodiment, and the description thereof is omitted.

FIG. 9 schematically shows a cross section of a part of the cutting insert 101 along the bisector (that is, the IX-IX line) of the first corner portion 5a in FIG. 8, similarly to FIG. 5A. In FIG. 9, the cross-sectional shape of the portion along the line β-β in FIG. 8 is shown by a broken line so as to overlap. Note that the cross section of the portion along the β-β line cannot be exactly superimposed on the cross section along the IX-IX line from the dimensional surface in reality, but the ridge 12 and the breaker projection 15 described later In order to facilitate understanding of the shape and configuration, the dimensions and the like are changed and schematically shown in FIG.

Also in the cutting insert 101, the raised part 12 is formed similarly to the cutting insert 1 described above. The raised portion 12 of the cutting insert 101 is configured in substantially the same manner as the raised portion 12 of the cutting insert 1.

Furthermore, the cutting insert 101 of this embodiment has a breaker protrusion 15 that protrudes toward the corner portion 5 in the chip breaker groove 11. The breaker protrusion 15 is formed inside the first corner portion 5 a and is formed continuously with the raised portion 12. Therefore, the breaker projection 15 extends along the bisector of the first corner portion 5a in the plan view of FIG. The breaker projection 15 has an effect of improving chip disposal when the cutting conditions and cutting are small. That is, there is an effect of expanding applicable cutting conditions. With the synergistic effect of the raised portion 12 and the breaker projection 15, it is possible to achieve an excellent cutting insert 101 having a long tool life while suppressing crater wear on the rake face 6 while obtaining excellent chip disposal. In the cutting insert 101, since the raised part 12 and the breaker projection part 15 are arranged so as to be connected to each other continuously from the cutting edge side, their synergistic effect is enhanced. Chips generated by cutting with the first cutting edge 8 a can flow through the rake face 6 and / or the raised portion 12 and then collide with the breaker protrusion 15. The presence of the raised portion 12 suppresses wear on the rake face as described above. Furthermore, not only when the cutting conditions are not small and the feed is small, for example, when cutting is performed under a cutting condition where the depth of cut is large or the feed is large, the chip is likely to curl to the breaker projection 15 by the raised portion 12, for example. Is reached, and the collision with the breaker projection 15 is further promoted. Therefore, by providing the raised portions 12 and the breaker projections 15 in the order of separating from the cutting edge, it is possible to further improve chip disposal.

Note that the breaker protrusion 15 of the cutting insert 101 of this embodiment is provided to have a breaker sub protrusion 15a protruding over the entire circumference. In other words, the rising wall surface 11r connected to the boss surface 16 of the chip breaker groove 11 has a two-stage structure over the entire circumference by the breaker protrusion 15, and as shown by the broken line in FIG. A cutting edge side portion 11ra. However, it is not limited to this. Various known shapes can be applied to the shape of the breaker protrusion 15 and the rising wall surface. The raised portion 12 of the cutting insert 101 of this embodiment intersects with the breaker protrusion 15. However, it is not limited to this. The raised portion 12 may be smoothly connected to the breaker protrusion 15. The raised portion 12 may be connected to the breaker protrusion 15 so that the effects of the raised portion 12 and the effect of the breaker protrusion 15 can be improved by interaction.

As described above, the features of the second embodiment have been described with respect to the first cutting edge 8a, but this description is similarly applied to the second cutting edge 8b. The same applies to the lower surface 3 side.

Next, a cutting insert 201 according to a third embodiment of the present invention will be described with reference to FIGS. 10 to 12B. In order to simplify the description, the same components as those described in the cutting inserts of the first and second embodiments are denoted by the same member numbers, and description thereof is omitted.

The cutting insert 201 has a ridge 18 in the chip breaker groove 11 in addition to the configuration of the cutting insert 1 of the first embodiment including the raised portion 12. Here, the ridge 18 indicates a portion raised from the rake face 6. At least one ridge 18 can be formed in association with one ridge 12. The cutting insert 201 has two ridges 18 for one ridge 12.

The ridge 18 is provided so as to forcibly separate chips from the rake face 6 and suppress the occurrence of crater wear on the rake face 6, as in the above-described raised portion 12. The ridge 18 in the cutting insert 201 of this embodiment extends while curving in a direction away from the first corner portion 5a. In particular, when the cutting insert 201 is viewed from the side facing the upper surface 2, the raised portion 12 extends from the width-enlarged portion 13 along the bisector of the corner portion (corresponding to the XIIA-XIIA cross-sectional line in FIG. 11A). On the other hand, the ridge 18 extends in a substantially arc shape. The two ridges 18 extend so as to sandwich the raised portion 12. Furthermore, each ridge 18 is curved so as to be convex toward the cutting edge.

FIG. 12A schematically shows the protrusion of the ridge 18 with respect to the rake face 6. Furthermore, in the cross-sectional schematic diagram of FIG. 12B, two ridges 18 located on both sides of the raised portion 12 are shown. 12A, a cross section of a part of the cutting insert 201 along the bisector (that is, the XIIA-XIIA line) of the first corner portion 5a in FIG. 11A is schematically shown in the same manner as FIG. 5A. Further, similarly, the cross-sectional shape of the portion along the γ-γ line in FIG. 11A is shown to be overlapped with a broken line. 12A conceptually shows the amount of protrusion of the ridge 18 with respect to the outline of the second rake face 6b, and the ridge 18 is projected onto the XIIA-XIIA cross section from the linear cutting edge 10a side. It is shown in The ridge 18 is connected to the first rake face 6a between the cutting edges and is formed so as to protrude from the second rake face 6b by the same amount or less than the raised portion 12, and reaches the vicinity of the bottom 11s.

When the ridge 18 is formed in such a shape, chips can be further lifted by the ridge 18 as compared with the case where only the raised portion 12 is provided. Therefore, the contact area between the chips and the rake face 6 is limited to a narrower range. For this reason, it can suppress more effectively that the heat | fever which a chip has is transmitted to the rake face 6 side, the effect which suppresses the crater abrasion of the rake face 6 becomes high, and also the wear of the protruding part 12 and the ridge 18 itself is also suppressed. Is done.

As described above, the features of the third embodiment have been described with respect to the first cutting edge 8a, but this description is similarly applied to the second cutting edge 8b. The same applies to the lower surface 3 side.

Next, a cutting insert 301 according to a fourth embodiment of the present invention will be described with reference to FIGS. In order to simplify the description, the same components as those described in the cutting inserts of the first to third embodiments are denoted by the same member numbers, and the description thereof is omitted.

The cutting insert 301 of this embodiment further includes both the breaker protrusion 15 and the ridge 18 in the chip breaker groove 11 including the raised portion 12. That is, the cutting insert 301 has a configuration in which the cutting insert 1 of the first embodiment is further incorporated with the breaker protrusion 15 of the second embodiment and the ridge 18 of the third embodiment. The cutting insert 301 of this embodiment is excellent in chip disposal due to the interaction of the raised portion 12, the breaker projection 15 and the ridge 18, and can suppress the occurrence of crater wear on the rake face 6, and therefore Tool life can be greatly extended.

15, a cross section of a part of the cutting insert 301 along the bisector (that is, the XV-XV line) of the first corner portion 5a in FIG. 14A is schematically shown in the same manner as FIG. 5A. Similarly to 5A, the cross-sectional shape of the portion along the δ-δ line in FIG. 14A is shown to be overlapped with a broken line. Further, FIG. 15 conceptually shows the amount by which the ridge 18 protrudes from the outline of the second rake face 6b, and the broken line shows the projection of the ridge 18 from the linear cutting edge 10a side. . Similarly to the ridge 18 of the cutting insert 201 of the third embodiment, the ridge 18 is connected to the first rake face 6a and protrudes from the second rake face 6b by the same amount or less than the raised portion 12. It is formed and reaches the vicinity of the bottom of the chip breaker groove 11.

This configuration is applied not only to the first cutting edge 8a but also to the second cutting edge 8b. The same applies to the lower surface 3 side.

The cutting insert of the present invention is not limited to the embodiment described above, and various modifications and additions are possible within a range not departing from the gist of the present invention. For example, the cutting insert can adopt various substantially polygonal plate-like outer shapes such as a substantially triangular plate shape and a substantially hexagonal plate shape. As schematically shown in FIG. 16 as an example of use of the cutting insert 1 of the first embodiment, the cutting inserts of the first to fourth embodiments are all lathe cutting inserts. Therefore, the cutting tool 1 in which the cutting insert 1 is detachably attached to the tip of the holder (tool body) 20 using a screw (not shown) as an attachment member is a work material that rotates around the axis O. W can be sent in the feed direction (arrow 2) with a predetermined cut (arrow A1). However, the present invention is not limited to such a lathe cutting insert, and may be applied to a milling cutting insert, for example. Specifically, the present invention may be applied to a cutting insert for an end mill including a ball end mill. In addition, the present invention can be applied to a cutting insert that employs a method of mounting various types of cutting tools on a tool body, for example, a so-called vertical insert type cutting insert. In the vertical insert type cutting insert, the rake face is defined on the peripheral side, the flank face is defined on a part and the end face of the peripheral side surface, and the cutting edge formed at the cross ridge line portion between the rake face and the flank face is provided. Some have a cutting edge portion along the corner portion, and some have a cutting edge portion (for example, a straight cutting edge portion) connected to the cutting edge portion of the corner portion. The configuration described in the above embodiment can be similarly applied to a rake face in a vertical insert type cutting insert having such a configuration. Alternatively, the present invention can also be applied to grooving cutting inserts and the like.

In the above-described embodiment, the present invention has been described with a certain degree of concreteness, but the present invention is not limited to this. It should be understood that various changes and modifications can be made to the present invention without departing from the spirit and scope of the claimed invention. That is, the present invention includes all modifications, applications, and equivalents included in the concept of the present invention defined by the claims.

Claims

A cutting insert,
A cutting edge portion extending along the corner portion (5), at least one cutting edge (8) formed at the intersection ridge line portion of the rake face (6) and the flank face (7) Including a cutting edge,
At least one ridge (12) formed to bulge in the rake face (6);
The raised portion (12) has a width-enlarging portion (13) that gradually increases as it approaches the cutting edge portion.
Cutting insert.
Two opposing end faces (2, 3), and the first end face (2) of the two end faces is substantially polygonal when the cutting insert is viewed from the side facing the first end face. Two end faces (2, 3);
A peripheral side surface (4) formed between the two end faces (2, 3) facing each other, and
The cutting edge is formed at an intersecting ridge line portion between the rake face (6) of the first end face and the flank face (7) of the peripheral side face.
The cutting insert according to claim 1.
The cutting insert according to claim 2, wherein the raised portion (12) is formed inside the corner portion and extends in a direction intersecting with the corner portion.
The cutting insert according to claim 2 or 3, wherein the raised portion (12) is inclined so as to gradually approach the second end surface (3) of the two end surfaces as the distance from the cutting edge (8) increases.
A chip breaker groove (11) including the rake face (6) and a rising wall surface is formed on the first end face, and the raised portion (12) crosses a bottom portion between the cutting edge and the rising wall surface. The cutting insert according to any one of claims 2 to 4, which extends as follows.
A chip breaker groove (11) including the rake face (6) and a rising wall surface is formed on the first end face,
The chip breaker groove (11) has a breaker projection (15) projecting inward thereof,
The breaker projection (15) connects with the raised portion (12),
The cutting insert according to any one of claims 2 to 5.
The cutting insert according to any one of claims 2 to 6, further comprising at least one ridge (18) formed so as to protrude from the rake face (6).
The cutting insert according to claim 7, wherein the ridge (18) extends while curving in a direction away from the corner portion.
When the cutting insert is viewed from the side facing the first end surface, the raised portion (12) extends from the widened portion (13) so as to extend along the bisector of the corner portion (5). The cutting insert according to claim 7 or 8, wherein the ridge (18) has a substantially arcuate shape and extends so as to sandwich the raised portion (12).
The said width expansion part (13) inclines so that it may approach gradually the 2nd end surface (3) of the said two end surfaces as it leaves | separates from the said cutting edge (8). Cutting insert as described.
In the corner portion (5), lands (6a, 17) are formed between the cutting edge portion and the width enlarged portion,
In the cross-sectional shape in the bisector direction at the corner (5), the inclination angle (θ2) of the inclination of the widened portion (13) is smaller than the rake angle (θ1) of the land (17). Item 11. A cutting insert according to Item 10.
12. The edge portion (14) on the cutting edge side associated with the width-enlarging portion (13) is configured as a plane substantially parallel to each of the two end faces, according to claim 2. Cutting inserts.
A plurality of cutting edges (8) are formed on the intersecting ridge line portion between the first end surface (2) and the peripheral side surface (4),
The first end face (2) is configured to be n times rotationally symmetric around the first axis (1b) (where n is a natural number of 2 or more),
The cutting insert according to any one of claims 2 to 12.
A plurality of cutting edges (8) are formed at the intersection ridge line portion between the second end surface (3) and the peripheral side surface (4), and the second end surface is defined to be orthogonal to the first axis. The cutting insert according to claim 13, wherein the cutting insert is configured to be 180 ° rotationally symmetric with respect to the first end surface around a biaxial line (1 c).
15. The associated edge portion (14) on the cutting edge side of the widened portion (13) extends along a virtual plane defined to be orthogonal to the first axis. Cutting insert.