阅读说明：本技术 切削刀片、车削刀具以及切削加工物的制造方法 (Cutting insert, turning tool, and method for manufacturing cut product ) 是由 山本佳祐 于 2020-03-23 设计创作，主要内容包括：切削刀片具有上表面、下表面、前端面、第一侧面、第二侧面、前切削刃、第一横切削刃以及第二横切削刃。上表面具有前刀面、第一横前刀面以及断屑突起。第一横切削刃具有随着远离前切削刃而接近下表面的倾斜部。断屑突起具有第一区域、第二区域以及第三区域。在从第一侧面侧进行侧视观察的情况下,第一区域位于比倾斜部远离下表面的位置。第二区域位于比第一区域接近前切削刃、且比倾斜部接近下表面的位置。第三区域位于比第一区域远离前切削刃、且比倾斜部接近下表面的位置。(The cutting insert has an upper surface, a lower surface, a front end surface, a first side surface, a second side surface, a front cutting edge, a first transverse cutting edge, and a second transverse cutting edge. The upper surface has a rake surface, a first lateral rake surface, and a chip breaking protrusion. The first side cutting edge has an inclined portion that approaches the lower surface as it goes away from the front cutting edge. The chip-breaking protrusion has a first region, a second region, and a third region. When viewed from the first side surface side in a side view, the first region is located farther from the lower surface than the inclined portion. The second region is located closer to the front cutting edge than the first region and closer to the lower surface than the inclined portion. The third region is located farther from the front cutting edge than the first region and closer to the lower surface than the inclined portion.)

1. A cutting insert, wherein,

the cutting insert has:

an upper surface;

a lower surface located on an opposite side of the upper surface;

a front face located between the upper surface and the lower surface;

a first side surface adjacent to the upper surface and the front end surface;

a second side surface located on an opposite side of the first side surface and adjacent to the upper surface and the front end surface;

a front cutting edge located at a boundary of the upper surface and the front end surface;

a first transverse cutting edge located at an intersection of the upper surface and the first side surface; and

a second transverse cutting edge located at the intersection of the upper surface and the second side surface,

the upper surface has:

a rake surface disposed along the front cutting edge and approaching the lower surface as being distant from the front cutting edge;

a first lateral rake surface disposed along the first transverse cutting edge and approaching the lower surface as moving away from the first transverse cutting edge; and

a chip breaking protrusion located farther from the first transverse cutting edge than the first transverse rake surface and extending along the first transverse rake surface,

the first side cutting edge has an inclined portion approaching the lower surface as it goes away from the front cutting edge,

the chip-breaking protrusion has, when viewed from the first side surface side,:

a first region located farther from the lower surface than the inclined portion;

a second region located closer to the front cutting edge than the first region and closer to the lower surface than the inclined portion; and

and a third region located farther from the front cutting edge than the first region and closer to the lower surface than the inclined portion.

2. The cutting insert of claim 1,

the inclined portion has, when viewed from the first side surface side,:

a first portion of concave curvilinear shape;

a linear second portion located closer to the front cutting edge than the first portion; and

a third portion of a straight line shape located farther from the front cutting edge than the first portion,

the first region is located closer to the front cutting edge than the third portion.

3. The cutting insert of claim 2,

the first region is located above the first portion when viewed from the first side surface side in a side view.

4. The cutting insert according to any one of claims 1 to 3,

the chip-breaking protrusion has a first chip-breaking wall surface that is distant from the lower surface with distance from the first lateral rake surface,

the first chip breaking wall surface has a portion whose width in a direction parallel to the front cutting edge becomes narrower as the chip breaking wall surface is separated from the front cutting edge in a plan view.

5. The cutting insert according to any one of claims 1 to 4,

the upper surface further having a bottom surface located between the first lateral rake surface and the chip breaking protrusion and parallel with respect to the lower surface,

the bottom surface has a portion that is wider in width in a direction parallel to the front cutting edge as the bottom surface is spaced apart from the front cutting edge in a plan view.

6. The cutting insert according to any one of claims 1 to 5,

the upper surface further includes, in a plan view:

a first secondary chip-breaking protrusion extending from the chip-breaking protrusion toward the front cutting edge; and

a second secondary chip-breaking protrusion located between the first secondary chip-breaking protrusion and the first transverse cutting edge and extending along the first secondary chip-breaking protrusion,

the second secondary chip-breaking protrusion is separated from the chip-breaking protrusion.

7. The cutting insert of claim 6,

the first sub chip-breaking protrusion extends closer to the front cutting edge than the second sub chip-breaking protrusion in a plan view.

8. The cutting insert according to claim 6 or 7,

the second sub chip-breaking protrusion extends further than the first sub chip-breaking protrusion to a region away from the front cutting edge in a plan view.

9. The cutting insert according to any one of claims 6 to 8,

the inclined portion has, when viewed from the first side surface side,:

a first portion of concave curvilinear shape;

a linear second portion located closer to the front cutting edge than the first portion; and

a third portion of a straight line shape located farther from the front cutting edge than the first portion,

the first and second sub chip-breaking protrusions are located inside the second portion in a plan view.

10. The cutting insert according to any one of claims 1 to 9,

the chip-breaking protrusion is located on a bisector of the front cutting edge in a plan view.

11. A cutting tool, wherein,

the cutting tool has:

a shank having a bar shape extending from a first end to a second end along a central axis and having a pocket located on a side of the first end; and

the cutting insert of any one of claims 1-10, located within the pocket.

12. A method for manufacturing a machined product, wherein,

the method for manufacturing the machined product comprises the following steps:

rotating the workpiece;

bringing the cutting tool according to claim 11 into contact with the workpiece which is rotating; and

and a step of separating the cutting tool from the workpiece.

Technical Field

The present disclosure relates generally to cutting inserts for use in the cutting process of a workpiece. Examples of the cutting process include turning and milling. Examples of the turning include outer diameter machining, inner diameter machining, grooving machining, and cutting machining.

Background

As a cutting insert used in cutting a workpiece such as a metal, there is, for example, a cutting insert described in japanese patent application laid-open No. 2017-196693 (patent document 1). The cutting insert described in patent document 1 includes a main body made of cemented carbide and a cutting edge portion made of diamond. In addition, the blade portion has an insert chip breaking recess.

In the cutting insert described in patent document 1, the height of the upper end of the chip-breaking wall surface of the chip-breaking recess is the same as the cutting edge. Therefore, the chips generated by the cutting edge can easily pass over the chip breaking wall surface. As a result, the chip breaking effect on the chips by the chip breaking wall surface may be insufficient.

Disclosure of Invention

An undefined example of the present disclosure is a cutting insert having an upper surface, a lower surface, a front end surface, a first side surface, a second side surface, a front cutting edge, a first side cutting edge, and a second side cutting edge. The lower surface is located opposite the upper surface. The front end surface is positioned between the upper surface and the lower surface. The first side surface is adjacent to the upper surface and the front end surface. The second side surface is located on the opposite side of the first side surface and is adjacent to the upper surface and the front end surface. The front cutting edge is located at the boundary of the upper surface and the front end surface. The first transverse cutting edge is located at the intersection of the upper surface and the first side surface. The second transverse cutting edge is located at the intersection of the upper surface and the second side surface.

The upper surface has a rake surface, a first lateral rake surface, and a chip breaking protrusion. The rake surface is disposed along the front cutting edge and approaches the lower surface as being distant from the front cutting edge. The first lateral rake surface is disposed along the first lateral cutting edge and approaches the lower surface with increasing distance from the first lateral cutting edge. The chip-breaking protrusion is located farther from the first transverse cutting edge than the first transverse rake surface and extends along the first transverse rake surface. The first side cutting edge has an inclined portion that approaches the lower surface as it goes away from the front cutting edge.

The chip-breaking protrusion has a first region, a second region, and a third region. When viewed from the first side surface side in a side view, the first region is located farther from the lower surface than the inclined portion. The second region is located closer to the front cutting edge than the first region and closer to the lower surface than the inclined portion. The third region is located farther from the front cutting edge than the first region and closer to the lower surface than the inclined portion.

Drawings

Fig. 1 is a perspective view showing an example of a cutting insert which is not limited.

Fig. 2 is a plan view of the cutting insert shown in fig. 1, as viewed from the upper surface side.

Fig. 3 is a plan view of the cutting insert shown in fig. 1 as viewed from the front end face side.

Fig. 4 is a plan view of the cutting insert shown in fig. 1, as viewed from the first side surface side.

Fig. 5 is an enlarged view of the area a1 shown in fig. 1.

Fig. 6 is an enlarged view of a region a2 shown in fig. 2.

Fig. 7 is an enlarged view of the area a3 shown in fig. 4.

Fig. 8 is an enlarged view of the VIII section of the turning tool shown in fig. 6.

Fig. 9 is an enlarged view of the IX section of the turning tool shown in fig. 6.

Fig. 10 is an enlarged view of the X-section of the turning tool shown in fig. 6.

Fig. 11 is a perspective view showing an example of a cutting tool which is not limited.

Fig. 12 is an enlarged view of the area a4 shown in fig. 11.

Fig. 13 is a schematic diagram illustrating a step in a manufacturing method of a machined product, which is not limited to this example.

Fig. 14 is a schematic diagram illustrating a step in a manufacturing method of a machined product, which is not limited to this example.

Fig. 15 is a schematic diagram illustrating a step in a manufacturing method of a machined product, which is not limited to this example.

Detailed Description

Cutting insert

Hereinafter, a cutting insert 1 (hereinafter, also simply referred to as an insert 1) according to a plurality of embodiments of the present disclosure, which are not limited, will be described in detail with reference to the drawings. However, in the drawings referred to below, for convenience of explanation, only main members necessary for explaining the respective embodiments are shown in a simplified manner. The blade 1 may thus be provided with any structural member not shown in the figures to which reference is made. The dimensions of the members in the drawings do not faithfully represent the actual dimensions of the structural members, the dimensional ratios of the members, and the like.

The insert 1 of the undefined embodiment can be used for so-called grooving. The insert 1 may be formed of one member, or may have a base portion 3 and a cutting portion 5 as shown in fig. 1. The insert 1 comprises a base portion 3 and a cutting portion 5, and may be generally polygonal plate-shaped as a whole. Specifically, as shown in fig. 1, the blade 1 may have a rectangular plate shape.

Examples of the material of the base 3 include a super-hard alloy, a cermet, and a ceramic. Examples of the composition of the cemented carbide include WC (tungsten carbide) -Co, WC-TiC (titanium carbide) -Co, and WC-TiC-TaC (tantalum carbide) -Co.

Here, WC, TiC, and TaC may be hard particles, and Co may be a binder phase. The cermet may be a sintered composite material obtained by compounding a metal and a ceramic component. Specifically, examples of the cermet include compounds containing TiC or TiN (titanium nitride) as a main component. However, the material of the base 3 is not limited to this.

Examples of the material of the cutting portion 5 include cemented carbide, PCD (polycrystalline diamond), cBN (cubic boron nitride), and the like. However, the material of the cutting portion 5 is not limited thereto.

When the material of the cutting portion 5 is, for example, PCD or cBN as described above and has a higher hardness than the base portion 3, the manufacturing cost of the insert 1 can be suppressed and the durability can be improved as compared with the case where the insert 1 is entirely PCD or cBN.

The cutting portion 5 may engage with the base portion 3. At this time, the cutting portion 5 may be joined to the base portion 3 using a joining member such as solder. The cutting portion 5 may be joined by being integrally fired with the base portion 3.

As shown in fig. 1, the insert 1 may have an upper surface 7, a lower surface 9, a front end surface 11, a first side surface 13, a second side surface 15, a front cutting edge 17, a first transverse cutting edge 19, and a second transverse cutting edge 21. As shown in fig. 1, the upper surface 7 may be polygonal in shape. As shown in fig. 2, when upper surface 7 is viewed in a planar manner (in a plan view), upper surface 7 may have a quadrilateral shape.

Here, the polygonal shape is not strictly limited to the polygonal shape. For example, the following shapes are also possible: at least one of the four corners of the upper surface 7 is rounded and slightly convex toward the outside in a plan view.

In addition, each of the four sides is not limited to a strict linear shape in a plan view. For example, at least one of the four sides may have a shape slightly convex toward the outside or a shape slightly concave toward the outside in a plan view.

The lower surface 9 is a surface located on the opposite side of the upper surface 7, and may be polygonal in shape. For example, the lower surface 9 may have a quadrilateral shape as in the upper surface 7. The lower surface 9 may be parallel with respect to the upper surface 7 or may also be inclined with respect to the upper surface 7. As shown in fig. 1, the lower surface 9 may be parallel to the flat surface 23 of the upper surface 7.

The front end face 11, the first side face 13 and the second side face 15 may be located between the upper surface 7 and the lower surface 9, respectively. The front end surface 11 may be connected to the lower surface 9 or may be separated from the lower surface 9. As shown in fig. 1, the front end surface 11 may be connected to the upper surface 7 and the lower surface 9.

The first side surface 13 and the second side surface 15 may be adjacent to the upper surface 7 and the front end surface 11. At this time, the second side surface 15 may be located at an opposite side of the first side surface 13. The distal end surface 11, the first side surface 13, and the second side surface 15 may be flat or curved.

As shown in fig. 2, the upper surface 7 may have a rectangular shape extending from the front end 7a (left side in fig. 2) toward the rear end 7b (right side in fig. 2) along the first central axis O1. In this case, the boundary between upper surface 7 and first side surface 13 and the boundary between upper surface 7 and second side surface 15 are longer than the boundary between upper surface 7 and distal end surface 11.

The size of the insert 1 is not particularly limited. For example, the length in the direction along the first central axis O1 in a plan view can be set to about 15 to 40 mm. The length in the direction perpendicular to the first central axis O1 in a plan view can be set to about 1 to 8 mm. The length of the first side surface 13 in the direction perpendicular to the first central axis O1 in a planar view (side view) can be set to about 5 to 12 mm.

In the case where the insert 1 includes the base portion 3 and the cutting portion 5, the length of the cutting portion 5 in the direction along the first central axis O1 in a plan view can be set to about 0.5 to 8 mm. The length of the cutting portion 5 in the direction perpendicular to the first central axis O1 in a plan view can be set to about 0.5 to 8 mm. The length of the cutting portion 5 in the direction perpendicular to the first central axis O1 in the side view of the first side surface 13 can be set to about 0.2 to 0.8 mm.

The cutting portion 5 may have a front cutting edge 17, a first side cutting edge 19, and a second side cutting edge 21 as cutting edges. The front cutting edge 17 may be located at the intersection of the upper surface 7 and the front end surface 11. In this case, the end cutting edge 17 may be located on the entire boundary between the upper surface 7 and the end surface 11, or may be located only on a part of the boundary between the upper surface 7 and the end surface 11.

The first transverse cutting edge 19 may be located at the intersection of the upper surface 7 and the first side surface 13. In this case, the first transverse cutting edge 19 may be located entirely at the boundary between the upper surface 7 and the first side surface 13, or may be located only in a part of the boundary between the upper surface 7 and the first side surface 13.

The second transverse cutting edge 21 may be located at the intersection of the upper surface 7 and the second side surface 15. In this case, the second transverse cutting edge 21 may be located entirely at the boundary between the upper surface 7 and the second side surface 15, or may be located only in a part of the boundary between the upper surface 7 and the second side surface 15.

The upper surface 7 may have a rake surface 25, a first lateral rake surface 27, and a chip breaking protrusion 29. The rake surface 25 may be disposed along the front cutting edge 17 and approach the lower surface 9 as going away from the front cutting edge 17. The rake surface 25 may be a region where chips (hereinafter, referred to as first chips for convenience) generated by the front cutting edge 17 flow.

When the end cutting edge 17 is inclined as described above, the first chips tend to advance in a direction away from the end cutting edge 17. Therefore, the first chip is less likely to be clogged in the vicinity of the front cutting edge 17. When the top surface 7 has the rake surface 25, the rake surface 11 can function as a flank surface.

The first lateral rake surface 27 may be disposed along the first lateral cutting edge 19 and approach the lower surface 9 with distance from the first lateral cutting edge 19. The first lateral rake surface 27 is a region where chips (hereinafter, referred to as second chips for convenience) generated by the first lateral cutting edge 19 flow.

When the first flank surface 27 is inclined as described above, the second cutting tends to advance in a direction away from the first side cutting edge 19. Therefore, the second chips are less likely to be clogged in the vicinity of the first transverse cutting edge 19. When the first lateral rake surface 27 is provided on the upper surface 7, the first side surface 13 can function as a flank surface.

The upper surface 7 may also have a second lateral rake surface 31. The second lateral rake surface 31 may be disposed along the second transverse cutting edge 21 and approach the lower surface 9 with increasing distance from the second transverse cutting edge 21. The second lateral rake surface 31 is a region where chips generated by the second lateral cutting edge 21 flow. When the second lateral rake surface 31 is provided on the upper surface 7, the second side surface 15 can function as a flank surface.

The chip-breaking protrusion 29 may be located farther from the first transverse cutting edge 19 than the first transverse rake surface 27. In addition, the chip breaking protrusion 29 protrudes in a direction away from the lower surface 9, and may extend along the first lateral rake surface 27. The chip-breaking protrusion 29 may have a function of bending the second chip. By bending the second chip, it is easy to avoid that the second chip extends too long. In addition, the chip-breaking protrusion 29 may have a function of bending the first chip.

As shown in fig. 1, the breaker projection 29 may have an inclined surface 33 and an upper end surface 57. The inclined surface 33 is disposed along the rake surface 25, the first lateral rake surface 27, and the second lateral rake surface 31, and may be inclined so as to be distant from the lower surface 9 as being distant from these rake surfaces.

The upper end surface 57 may be a flat surface parallel to the lower surface 9 and arranged along the inclined surface 33. Alternatively, the breaker projection 29 may have a flat upper end surface 57 and an inclined surface 33 located between the upper end surface 57 and the rake surface.

The first transverse cutting edge 19 may have an inclined portion 35 approaching the lower surface 9 with distance from the front cutting edge 17. When the first side cutting edge 19 has the inclined portion 35, the cutting resistance applied to the first side cutting edge 19 can be reduced. In addition, when the first side cutting edge 19 has the inclined portion 35, the second chips easily advance in a direction away from the end cutting edge 17. Therefore, the first chip and the second chip are less likely to be entangled, and the chip discharge performance is improved.

The chip-breaker protrusion 29 may have a first region 37, a second region 39 and a third region 41. In the case of side view from the first side surface 13 side, the first region 37 may be located farther from the lower surface 9 than the inclined portion 35. The second region 39 may be located closer to the front cutting edge 17 than the first region 37 and closer to the lower surface 9 than the inclined portion 35. The third region 41 may be located farther from the front cutting edge 17 than the first region 37 and closer to the lower surface 9 than the inclined portion 35.

When the chip-breaking protrusion 29 has the first region 37, the second chips generated by the first transverse cutting edge 19 and advancing on the first transverse rake surface 27 can be stably bent in the first region 37.

In addition, when the chip breaking protrusion 29 has the second region 39, the space of the rake surface 25 can be stably secured. Therefore, for example, when the cutting process with a small feed amount is performed as in the case of performing the cutting process using only the front cutting edge 17 and the case of performing the cutting process using only the portion along the second region 39 of the front cutting edge 17 and the first side cutting edge 19, the first chips and the second chips are less likely to be clogged in the vicinity of the front cutting edge 17.

In addition, the first chip easily and stably contacts the inclined surface 33 of the chip-breaking protrusion 29. As a result, it is easy to avoid the first chip extending too long beyond the chip-breaking protrusion 29.

In addition, in the case where the chip-breaking protrusion 29 has the third region 41, the second chips are less likely to be clogged in the vicinity of the first side cutting edge 19. When the cutting process is performed using a portion along the third region 41 in addition to the portion along the first region 37 and the second region 39 of the first side cutting edge 19, the width of the second chip tends to increase.

In the case where the chip-breaking protrusion 29 has the third region 41, the second chips generated by the portion of the first transverse cutting edge 19 along the third region 41 easily pass over the chip-breaking protrusion 29. Therefore, the chip-breaking effect by the chip-breaking protrusion 29 is prevented from becoming excessively strong, and the second chip discharge performance is improved.

In addition, in the case where the third region 41 is farther from the front cutting edge 17 than the first region 37, the chips generated by the portion of the first counter cutting edge 19 along the first region 37 are easily pulled by the chips generated by the portion of the first counter cutting edge 19 along the third region 41. Therefore, the second chip easily advances in a direction away from the end cutting edge 17. This makes the machined surface of the workpiece formed by the end cutting edge 17 less likely to be damaged.

The inclined portion 35 of the first cross cutting edge 19 may have a first portion 43, a second portion 45, and a third portion 47. The first portion 43 may have a concave curved shape when viewed from the side of the first side surface 13. The second portion 45 may be located closer to the front cutting edge 17 than the first portion 43. The third portion 47 may be located further from the front cutting edge 17 than the first portion 43.

When viewed from the side of the first side surface 13, each of the second portion 45 and the third portion 47 may have a linear shape. At this time, the inclination angle θ 1 of the second portion 45 with respect to the lower surface 9 may be greater than the inclination angle θ 2 of the third portion 47 with respect to the lower surface 9.

When the inclination angle θ 1 of the second portion 45 located relatively close to the end cutting edge 17, that is, located near the end 7a of the insert 1, is relatively large in the inclined portion 35, chatter vibration during cutting can be suppressed.

Further, when the inclination angle θ 2 of the third portion 47 of the inclined portion 35 located relatively far from the end cutting edge 17 is relatively small, rather than the inclination angle of the entire inclined portion 35 being large, the thickness of the insert 1 from the lower surface 9 to the third portion 47 can be easily ensured to be thick. Therefore, the durability of the blade 1 is high.

In addition, when the concave curved first portion 43 is located between the second portion 45 and the third portion 47, the first portion 43, the second portion 45, and the third portion 47 are smoothly connected, and thus the cutting load is less likely to concentrate on a specific portion of the inclined portion 35.

In the case where the inclined portion 35 has the first portion 43, the second portion 45, and the third portion 47, as shown in fig. 6, the first region 37 may be located closer to the end cutting edge 17 than the third portion 47. The thickness of the chip generated at the third portion 47 where the inclination angle θ 2 is relatively small is thicker than the thickness of the chip generated at the second portion 45 where the inclination angle θ 1 is relatively large.

When the first region 37 located farther from the lower surface 9 than the inclined portion 35 is located closer to the end cutting edge 17 than the third portion 47, the thickness tends to be large, and chips generated at the third portion 47 tend to get over the chip-breaking protrusion 29. Therefore, the swarf is not easily clogged.

In addition, as in the example shown in fig. 8, the first region 37 may be located above the first portion 43 when viewed from the side of the first side surface 13. In this case, the space of the rake surface 25 can be more stably secured. Therefore, in the case of performing cutting with a small feed amount, the possibility that chips are clogged in the vicinity of the end cutting edge 17 is smaller.

The inclined surface 33 in the chip-breaking protrusion 29 may have a first chip-breaking wall surface 49 disposed along the first rake surface. In other words, the chip-breaking protrusion 29 may have the first chip-breaking wall surface 49 that is distant from the lower surface 9 with distance from the first lateral rake surface 27.

The first chip-breaking wall surface 49 may have a first portion 49a whose width in a direction parallel to the front cutting edge 17 becomes narrower as it goes away from the front cutting edge 17 in a plan view.

Here, the first portion 49a may be located in the third region 41 in the chip-breaking protrusion 29. In the case where the first portion 49a, which narrows in width in a direction parallel to the front cutting edge 17, is located in the third region 41, chips generated by the portion of the first cross cutting edge 19 along the third region 41 more easily pass over the chip-breaking protrusion 29.

The upper surface 7 may also have a bottom surface 51 parallel to the lower surface 9. The bottom surface 51 may be located, for example, between the first lateral rake surface 27 and the breaker projection 29. The bottom surface 51 may have a second portion 51a whose width in a direction parallel to the front cutting edge 17 becomes wider as being distant from the front cutting edge 17 in a plan view. Here, the second portion 51a may be disposed along the third region 41 in the chip-breaking protrusion 29.

When the second portion 51a, which has a wider width in a direction parallel to the end cutting edge 17, is disposed along the third region 41, it is easy to ensure a wider width of the breaker groove formed by the first lateral rake surface 27, the second portion 51a, and the third region 41. Therefore, chips generated by the portion of the first transverse cutting edge 19 along the third region 41 more easily pass over the chip-breaking protrusion 29.

The upper surface 7 may further include a first sub chip-breaking protrusion 53 and a second sub chip-breaking protrusion 55. The first sub chip-breaking protrusion 53 may extend from the chip-breaking protrusion 29 toward the front cutting edge 17 in a plan view.

The second secondary chip-breaking protrusion 55 may be located between the first secondary chip-breaking protrusion 53 and the first transverse cutting edge 19 and extend along the first secondary chip-breaking protrusion 53. As shown in fig. 6, the first sub chip-breaking protrusion 53 and the second sub chip-breaking protrusion 55 may be located closer to the first side cutting edge 19 than the first center axis O1 in a plan view.

The upper ends of the first and second sub chip-breaking protrusions 53 and 55 may be lower than the upper end surface 57 of the chip-breaking protrusion 29. Here, low may mean that the height from the lower surface 9 is low.

In the case of having the first and second sub chip-breaking protrusions 53 and 55 whose upper ends are lower than the upper end surface 57 of the chip-breaking protrusion 29, it is easy to secure a space of the rake surface 25 and to control the flow direction of the first chip by the first and second sub chip-breaking protrusions 53 and 55.

The first sub chip-breaking protrusion 53 may be separate from the chip-breaking protrusion 29 or may be contiguous with the chip-breaking protrusion 29. As shown in fig. 6, when the first sub chip-breaking protrusion 53 is in contact with the chip-breaking protrusion 29, the first chips generated by the front cutting edge 17 and flowing on the first sub chip-breaking protrusion 53 easily flow smoothly toward the chip-breaking protrusion 29. Therefore, the first chips are less likely to be clogged when flowing over the first sub chip-breaking protrusions 53 and the chip-breaking protrusions 29.

The second sub chip-breaking protrusion 55 may be separate from the chip-breaking protrusion 29 or may be in contact with the chip-breaking protrusion 29. As shown in fig. 6, when the second sub chip-breaking protrusion 55 is separated from the chip-breaking protrusion 29, the second chips are likely to be brought into contact with the second sub chip-breaking protrusion 55 and the chip-breaking protrusion 29 in stages.

Therefore, the second chip can be bent stably by the second sub chip-breaking protrusion 55 and the chip-breaking protrusion 29. As a result, the second chips are less likely to flow toward the machined surface of the workpiece formed by the end cutting edge 17, and the machined surface is less likely to be damaged.

The first sub chip-breaking protrusion 53 may extend closer to the front cutting edge 17 than the second sub chip-breaking protrusion 55 in a plan view. In the case where the first sub chip-breaking protrusion 53 is relatively extended to the vicinity of the front cutting edge 17, the flow direction of the first chips is easily controlled by the first sub chip-breaking protrusion 53.

In addition, in the case where the second secondary chip-breaking protrusion 55 is relatively distant from the front cutting edge 17, it is easy to secure a space free from protrusion in the vicinity of the corner of the upper surface 7 where the front cutting edge 17 intersects with the first side cutting edge 19. Therefore, the first chips and the second chips are less likely to be clogged.

The second sub chip-breaking protrusion 55 may extend further away from the front cutting edge 17 than the first sub chip-breaking protrusion 53 in a plan view. As shown in fig. 6, when the second sub chip-breaking protrusion 55 is separated from the chip-breaking protrusion 29, the second chips are likely to be brought into contact with the second sub chip-breaking protrusion 55 and the chip-breaking protrusion 29 in stages.

When the inclined portion 35 of the first side cutting edge 19 has the first portion 43, the second portion 45, and the third portion 47, the first sub chip-breaking protrusion 53 and the second sub chip-breaking protrusion 55 may be located inside the second portion 45 in a plan view as shown in fig. 6. That is, the first and second sub chip-breaking protrusions 53 and 55 may be located closer to the front cutting edge 17 than the first portion 43 in the direction along the first center axis O1.

Since the first portion 43 has a concave curved shape, chips generated in the first portion 43 are more likely to be clogged than chips generated in the second portion 45 and the third portion 47. However, when the first and second sub chip-breaking protrusions 53 and 55 are arranged as described above, chips generated at the first portion 43 of the first side cutting edge 19 are less likely to be clogged.

In a plan view as shown in fig. 6, the chip-breaking protrusion 29 may be located on a bisector of the front cutting edge 17. In other words, the breaker projection 29 may be located on the first center axis O1 in a plan view as shown in fig. 6. In this case, the space for the second lateral rake surface 31 is easily secured. Therefore, in the cutting process using the second side cutting edges 21 instead of the first side cutting edges 19, it is easy to avoid the situation in which the chips generated by the second side cutting edges 21 extend too long.

As shown in fig. 1 and the like, the blade 1 may have a through hole 59 that opens in the first side surface 13 and the second side surface 15. As shown in fig. 1, the through hole 59 may be formed from the center of the first side surface 13 toward the center of the second side surface 15.

The through hole 59 can be used for inserting, for example, a screw when the insert 1 is fixed to the holder. The insert 1 can be attached to the holder 3 by inserting a screw into the through hole 59 of the insert 1, inserting the tip of the screw into a screw hole formed in the holder, and fixing the screw to the screw hole. When the insert 1 is fixed to the holder, for example, a clamping member may be used instead of the screw.

< cutting tool >

Next, a plurality of embodiments of the cutting tool 101 of the present disclosure will be described with reference to the drawings.

The cutting tool 101 of the undefined embodiment may have a shank 103 as well as a blade 1. As shown in fig. 11, the shank 103 may be a rod shape extending from a first end 103a (lower left end in fig. 11) to a second end 103b (upper right end in fig. 11) along the second center axis O2. In addition, the tool shank 103 may have a tool pocket 105 as well as a threaded bore.

The pocket 105 is a portion where the insert 1 is attached, and may be located on the first end 103a side of the holder 103. As shown in one example in fig. 12, the knife slot 105 may be located in the shank 103 at a location that includes the first end 103 a. Therefore, as shown in an example in fig. 12, the sipe 105 may be open at the first end 103 a.

The pocket 105 may have a bearing surface 109 and a restricting side surface 111 as surfaces against which the insert 1 abuts. The limiting side 111 may be inclined with respect to the bearing surface 109. Therefore, the support surface 109 and the regulation side surface 111 of the pocket 105 can be distinguished. The bearing surface 109 may extend parallel to the second central axis O2. In addition, the restricting side 111 may be inclined with respect to the second central axis O2.

The screw hole is a surface to which a screw 113 for fixing the insert 1 to the holder 103 is attached. The threaded hole may open at the pocket 105. For example, the threaded hole may open at the bearing surface 109.

Examples of the member constituting the shank 103 include steel, cast iron, and aluminum alloy. In particular, when steel is used for these members, the toughness of the shank 103 is high. The size of the shank 103 may be set as appropriate according to the size of the workpiece.

As an example shown in fig. 11, a cutting tool 101 used for so-called turning can be shown. The cutting insert 101 of the embodiment, which is not limited to the above, can be used for grooving machining, but is not limited to such machining. For example, the cutting tool 101 is used for inner diameter machining, outer diameter machining, and infeed machining, and has no problem.

< method for producing machined article >

Next, a method for manufacturing a machined product according to various embodiments of the present disclosure will be described with reference to the drawings.

The machined product 201 can be produced by cutting the workpiece 203. In an embodiment that is not limited, grooving is exemplified as the cutting process. The method for manufacturing the machined product 201 according to the embodiment which is not limited to the above may include the following steps. Namely, it may include:

(1) a step of rotating the workpiece 203;

(2) a step of bringing the cutting tool 101, which is typified by the above-described embodiment, into contact with the rotating workpiece 203; and

(3) and a step of separating the cutting tool 101 from the workpiece 203.

More specifically, first, as shown in fig. 13, the cut piece 203 may be rotated about the axis D in the direction D1. Then, the cutting tool 101 can be relatively brought close to the workpiece 203 by moving the cutting tool 101 in the direction D2. Next, as shown in fig. 14, the first cutting edge of the cutting tool 101 may be brought into contact with the workpiece 203 to cut the workpiece 203.

At this time, the workpiece 203 can be cut while the cutting tool 101 is moved in the direction D3, thereby performing grooving. Then, as shown in fig. 15, the cutting tool 101 can be relatively moved away from the workpiece 203 by moving the cutting tool 101 in the direction D4.

As shown in fig. 13, the cutting tool 101 can be moved closer while the shaft D is fixed and the workpiece 203 is rotated. As shown in fig. 14, the workpiece 203 can be cut by bringing the tip cutting edge of the blade into contact with the rotating workpiece 203. As shown in fig. 15, the cutting tool 101 may be separated while the workpiece 203 is rotated.

In the cutting process in the manufacturing method of the embodiment, which is not limited, the cutting tool 101 may be moved to contact the workpiece 203 with the cutting tool 101. In addition, the cutting tool 101 can be moved away from the workpiece 203 by moving the cutting tool 101. However, the manufacturing method of the embodiment is not limited to such a configuration.

For example, in the step (1), the workpiece 203 may be brought close to the cutting tool 101. Similarly, in the step (3), the workpiece 203 may be separated from the turning tool 101. When the cutting process is continued, the step of bringing the cutting edge of the blade into contact with different portions of the workpiece 203 may be repeated while the workpiece is rotated.

Representative examples of the material of the workpiece 203 include carbon steel, alloy steel, stainless steel, cast iron, and nonferrous metals.

Description of the reference numerals

1. cutting blade

3. base

5. cutting part

7. upper surface

7 a. front end

7 b. rear end

9. lower surface

11. front end face

13. first side

15. second side

17. front cutting edge

19 first transverse cutting edge

21. second transverse cutting edge

23. flat surface

25 DEG to the DEG

27. first transverse rake face

29. chip breaking protuberance

31. second transverse rake face

33. inclined plane

35. inclined part

37. first region

39. second region

41. third region

43. first site

45. second site

47. third site

49. first chip breaker wall

49 a. first part

51. bottom surface

51 a. second part

53. first secondary chip-breaking projection

55. second set of chip breaking protrusions

57. upper end face

59. through hole

101. cutting tool

103. knife handle

103 a. first end

103 b. second end

105. knife slot

109. bearing surface

111 · confinement profile

113. screw

201. cutting workpiece

203. the workpiece

O1. first central axis

O2. second central axis.