CN104853867A

CN104853867A - Cutting insert, cutting tool, and method for manufacturing cut article using same

Info

Publication number: CN104853867A
Application number: CN201380065526.1A
Authority: CN
Inventors: 樽口晃
Original assignee: Kyocera Corp
Current assignee: Kyocera Corp
Priority date: 2012-12-21
Filing date: 2013-12-20
Publication date: 2015-08-19
Anticipated expiration: 2033-12-20
Also published as: WO2014098226A1; JP6174602B2; CN104853867B; JPWO2014098226A1

Abstract

A cutting insert is provided with a cutting part having an upper surface, a lower surface, a side surface connected to the upper surface and the lower surface, and a cutting blade located at the line of intersection between the upper surface and the side surface, the cutting blade comprises a first cutting blade which is located on the tip side of the cutting part and has an outwardly protruding arc shape when viewed from above, the upper surface comprises a breaker which has a rake surface located inside the first cutting blade and inclined downward toward the inside, and a rising surface located adjacent to the rake surface on the back end side and inclined upward toward the back end side, and when viewed from above, the breaker has, on the back end side with respect to both ends of the first cutting blade, a wide portion with a largest width in the direction orthogonal to a virtual straight line extending from the back end side to the tip side of the cutting part.

Description

Cutting insert, cutting element and use the manufacture method of machining thing of this cutting element

Technical field

The present invention relates to cutting insert, cutting element and use the manufacture method of machining thing of this cutting element.

Background technology

(following at the cutting insert of grooving use and profiling, be sometimes referred to as " edge cutter ") in, in order to discharge the chip of generation swimmingly, carry out various research (for example, referring to Japanese Unexamined Patent Application Publication 2005-515905 publication) in edge cutter for the treatment of the shape of the rake face of chip all the time.

In the edge cutter described in this patent document, cutting head has the cutting edge of circular shape at the intersection place of the chip surface of upper surface side and the rear knife face of side.And, on chip surface, across be arranged on cutting head front chip fracture recess and there is a pair convex shaped part.

Utilize the edge cutter with such structure, when carrying out Xiyanping injection, the chip generated by the cutting edge of circular shape is thicker at the fore-end of cutting edge, along with thinning towards rear end side.And chip easily diminishes in thicker curling footpath, part place, and easily becomes large in thinner curling footpath, part place, there is the trend forming convex form in the section shape of the chip of therefore this edge cutter generation.

But, because chip fracture recess and a pair convex shaped part are arranged on the front of cutting head, therefore cannot give full play to the function that the chip of convex form is guided, in addition, there is the possibility that chip cannot be made to reduce in the direction of the width.Its result is, there is chip and is wrapped in the possibility be cut on part.

Therefore, for the edge cutter of grooving processing, require the discharge improving the chip generated by cutting edge.

One of problem of the present invention is to provide the cutting insert of chip discharge excellence, cutting element and uses the manufacture method of machining thing of this cutting element.

Summary of the invention

Cutting insert involved by embodiments of the present invention possesses: cutting portion, and it has the cutting edge at upper surface, lower surface, the side be connected with described upper surface and described lower surface and the place of intersection portion that is positioned at described upper surface and described side; And fixed part, it is positioned at the rear end side of described cutting portion when carrying out top view to described cutting portion.When top view, described cutting edge has: be positioned at the front of described cutting portion and the first cutting edge of circular shape convex laterally; And a pair second cutting edges of the rectilinear form to be connected respectively with the two ends of described first cutting edge.Described upper surface has chip breaking portion, and described chip breaking portion has: be positioned at described first cutting edge inner side and along with the rake face tilted downwards towards inner side; And with described rake face the rear end side of described cutting portion be disposed adjacent and along with the rear end side towards described cutting portion tilt upward erect face.When top view, described chip breaking portion leans on the rear end side of described cutting portion to have wide width part at the two ends than described first cutting edge, and the width of described wide width part on the direction orthogonal with the imaginary line extended from the rear end side of described cutting portion towards front is maximum.

Accompanying drawing explanation

Fig. 1 is the stereogram of the cutting insert represented involved by one embodiment of the present invention.

Fig. 2 is the figure of the cutting insert representing Fig. 1, and (a) is the figure observing from outer surface side and obtain, and (b) is the figure observing from inner surface and obtain.

Fig. 3 is the figure of the cutting insert representing Fig. 1, and (a) is the overall diagram of observing a cutting portion from upper surface and obtaining, and (b) is the partial enlarged drawing of the cutting portion representing (a).

Fig. 4 is the partial enlarged drawing of the cutting portion of the cutting insert representing Fig. 1.

Fig. 5 is the figure of each section of the cutting portion representing Fig. 4, and (a) is the amplification view cut open along A-A line, and (b) is the amplification view cut open along B-B line, and (c) is the amplification view cut open along C-C line.

Fig. 6 is by the amplification view shown in Fig. 5 (a) amplification.

Fig. 7 is the figure of each section of the cutting portion representing Fig. 4, and (a) is the amplification view cut open along D-D line, and (b) is the amplification view cut open along E-E line, and (c) is the amplification view cut open along F-F line.

Fig. 8 is the figure of each section of the cutting portion representing Fig. 4, and (a) is the amplification view cut open along G-G line, and (b) is the amplification view cut open along H-H line, and (c) is the amplification view cut open along I-I line.

Fig. 9 is the figure of the cutting element representing one embodiment of the present invention, and (a) is side view, and (b) is top view, and (c) is stereogram.

Figure 10 is by the enlarged side view shown in the amplification of the front of the cutting element of Fig. 9 (a).

Figure 11 is the schematic illustration figure of the manufacture method of the machining thing representing one embodiment of the present invention.

Figure 12 is the top view of the cutting element representing other embodiments of the present invention.

Detailed description of the invention

< cutting insert >

Below, with reference to Fig. 1 ~ Fig. 8, the cutting insert 1 (hreinafter referred to as edge cutter 1) involved by one embodiment of the present invention is described.

As shown in Fig. 1 ~ Fig. 3 etc., edge cutter 1 roughly possesses: cutting portion 1a; And fixed part 1b, it is positioned at the rear end side of cutting portion 1a when carrying out top view to cutting portion 1a as shown in Fig. 3 (a), and is fixed on cutter holder.And as shown in Figure 1, cutting portion 1a possesses: upper surface 2, lower surface 3, the side 4 be connected with upper surface 2 and lower surface 3, be formed in the cutting edge 5 in upper surface 2 and the intersection portion of side 4.

More specifically, in the present embodiment, as shown in Figure 1 and Figure 2, the interarea of edge cutter 1 forms leg-of-mutton plate shape, have cutting portion 1a respectively, and the region between these three cutting portion 1a has fixed part 1b in leg-of-mutton bight.As an example of the size of edge cutter 1, such as, the diameter of inscribed circle of a triangle can be set to 9.52 ~ 12.7mm, width (tread degree) is set to 0.33 ~ 5mm, height (thickness) is set to 3 ~ 5mm.

Be preferably, edge cutter 1 is made up of the material being such as coated with film on the sintered bodies such as superhard alloy, cermet, pottery.This film is for improving the mar proof of edge cutter 1.As the composition of film, such as, titanium sub-group compound or the aluminium oxide etc. such as titanium carbide, titanium nitride, titanium carbonitride can be enumerated.As long as film is at least one deck, also can be made up of multilayer.It should be noted that, edge cutter 1 also can be made up of the sintered body not having tunicle to cover.

Edge cutter 1 involved by such present embodiment can be used in grooving processing (internal diameter processing) of internal diameter, grooving processing (external diameter processing) of external diameter and the turnery processing as cut off and processing.Below, the detailed content of each inscape is described successively.

(about cutting portion)

Cutting portion 1a is the position of carrying out the generation of chip and the main of discharge when machining, and with regard to its shape, as shown in Fig. 3 etc., when top view, the position of the 1af side, front end of cutting portion 1a is circular shape.

Cutting edge 5 plays Main Function when slicing part, and as mentioned above, cutting edge 5 is positioned at the intersection portion of upper surface 2 and side 4.

In the present embodiment, as shown in Fig. 3 (b), when top view, cutting edge 5 has: the first cutting edge 5a being positioned at the circular shape convex laterally of the 1af side, front end of cutting portion 1a; And a pair second cutting edge 5b of the rectilinear form to be connected respectively with the two ends of the first cutting edge 5a.

In addition, also a pair second cutting edge 5b can be set to the structure be not parallel to each other in top view phase.As shown in Figure 3, be preferably, a pair second cutting edge 5b are along with such structure close to each other towards rear end side.In the edge cutter 1 of present embodiment, the first cutting edge 5a and the second cutting edge 5b is that outland is arranged with the line L5 in Fig. 3 (b).First cutting edge 5a and the second cutting edge 5b shows greatly E-E hatching in Fig. 4 as border.

Cutting edge 5 involved by present embodiment has such structure, therefore, when carrying out grooving processing (internal diameter processing) of internal diameter, grooving processing (external diameter processing) of external diameter and the turnery processing as cut off and processing, the first cutting edge 5a is mainly utilized to cut being cut part.

As shown in Fig. 3 (b), upper surface 2 has the land 7 of the inner side being positioned at cutting edge 5 when top view and chip breaking portion 6 (rake face 61 and erect face 62).Here, in this manual, if without special records, " inner side " refers to, the central side of cutting portion 1a when carrying out top view to cutting portion 1a.

Land 7 mainly plays the effect of reinforcing cutting edge 5, as shown in Fig. 3, Fig. 5 ~ Fig. 7, is mainly positioned at along the narrower region of the width of the first cutting edge 5a.In the present embodiment, land 7 is between the first cutting edge 5a and rake face 61 and arrange continuously with the first cutting edge 5a, and as shown in Figure 6, tilts relative to datum line S1a along with leaving from the first cutting edge 5a with tilt angle alpha 1.Be preferably, make the tilt angle alpha 1 of land 7 and the tilt angle alpha 2 of rake face 61 meet the relation of α 1 < α 2.

In the present embodiment, land 7 tilts downwards along with leaving from the first cutting edge 5a.Be preferably, the tilt angle alpha 1 of land 7 is such as set as 0 ~ 25 °.In addition, in the present embodiment, as shown in Fig. 3 (b), when top view, the interval between the first cutting edge 5a and chip breaking portion 6 and the length of land 7 are the shortest with the central 5af continuous print part place of the first cutting edge 5a.

The central 5af of the first cutting edge 5a in present embodiment is positioned at the side foremost of cutting portion 1a.Therefore, the central 5af of the first cutting edge 5a can be called the front end of the first cutting edge 5a.

In this manual, " angle of inclination " refers to, as shown in Figure 10 relative to the meaning of the angle of datum line (face) the S1a inclination of regulation.More specifically, as shown in Figure 10, refer to being provided with the cutter holder 21 of edge cutter 1 under the state left standstill by the lower surface 213 of cutter holder 21, relative to the angle that datum line (face) S1a parallel with cutter holder lower surface 213 tilts.And, so-called positive inclination is just set to, so-called negative inclination is set to negative and judges.

Chip breaking portion 6 is mainly played the chip making to be generated by cutting edge 5 and carries out the curling or distortion such as constriction the effect of externally discharging in the direction of the width.Specifically, as shown in Fig. 3 (b) etc., chip breaking portion 6 has: be positioned at the first cutting edge 5a inner side and along with the rake face 61 tilted downwards towards inner side, be adjacent to arrange with the rear end side of rake face 61 and along with the face that erects 62 tilted upward towards rear end side.In Fig. 3 (b) and Fig. 4, show rake face and erect the boundary B o between face.In the present embodiment, as shown in Fig. 3 (b), boundary B o is towards the convex curve shape of the central 5af of the first cutting edge 5a when top view.

And, in the present embodiment, as shown in Fig. 3 (b), when top view, chip breaking portion 6 leans on the rear end side of cutting portion 1a to have wide width part 6W at the two ends than the first cutting edge 5a, and the width of this wide width part 6W on the direction orthogonal with the imaginary line X extended from the rear end side of cutting portion 1a towards front is maximum.Here, the width (length) on orthogonal with imaginary line X direction refers to the distance on the direction orthogonal with imaginary line X.

In addition, as imaginary line X extend direction, refer to from the direction that the rear end side of cutting portion 1a extends towards front, the cutting portion 1a being benchmark with the fixed part 1b of cutting insert 1 give prominence to direction.In the cutting insert 1 of present embodiment, the cutting portion 1a direction parallel to the outer surface 11b and inner surface 12b with the fixed part 1b shown in Fig. 2 is outstanding.Therefore, when top view, the bearing of trend of imaginary line X is parallel with outer surface 11b and inner surface 11a.In addition, when top view, the direction orthogonal with imaginary line X is orthogonal with outer surface 11b and inner surface 11a.

Thus, for the position generated near the two ends of the first cutting edge 5a in chip, at the wide width part 6W place in chip breaking portion 6 being positioned at more rearward position, can constriction and can path be curled into by the face that erects 62 in chip breaking portion 6 in the direction of the width by rake face 61.Therefore, the chip that the edge cutter 1 involved by present embodiment generates for the first cutting edge 5a by circular shape convex laterally can play excellent discharge.

In addition, as shown in Fig. 3 (b), when top view, chip breaking portion 6 is positioned at the part of rear end side along with the part being positioned at rear end side from the central 5af relative to the first cutting edge 5a towards the two ends relative to the first cutting edge 5a along the length on the direction of imaginary line X and diminishes.In the present embodiment, the central 5af of the first cutting edge 5a is identical position with the front end of the first cutting edge 5a.Thereby, it is possible to the thicker portion deforms making the central 5af in chip is large footpath, the thinner portion deforms at the two ends of chip is made to be path.Therefore, it is possible to more effectively externally discharge the chip that thickness is different according to position.

And, in the present embodiment, when top view, rake face 61 and erect face 62 any one be all be positioned at the part of rear end side along with the part being positioned at rear end side from the central 5af relative to the first cutting edge 5a towards the two ends relative to the first cutting edge 5a along the length on the direction of imaginary line X and diminish.Thereby, it is possible to more effectively play chip discharge as described above.

In addition, when top view, chip breaking portion 6 straight line parallel with imaginary line X has lowest part (position of lowest order) 6L and highest portion (position of highest order) 6H by the central 5af of the first cutting edge 5a.Thereby, it is possible to the thicker portion deforms making the central authorities in chip is large footpath, makes the thinner portion deforms at the two ends of chip be path, therefore more effectively externally discharge the chip that thickness is different according to position.It should be noted that, in Fig. 3 (b), because imaginary line X is arranged in the mode of the central 5af comprising the first cutting edge 5a, therefore, when top view, lowest part (position of lowest order) 6L and highest portion (position of highest order) 6H is positioned on imaginary line X.

Here, in this manual, " high position " refers to, the relation of the upper-lower position when being arranged on by edge cutter 1 under the state on cutter holder, the lower surface of cutter holder is standing as mounting surface.It should be noted that, in this manual, " low level " and " high position " are contrary concepts.

Rake face 61 mainly plays and the chip generated by cutting edge 5 is nuzzled up and the effect of rearward flowing, and as shown in Figure 6, rake face 61 arranges along cutting edge 5 and tilts with tilt angle alpha 2 along with towards inner side.In the present embodiment, as shown in Figure 6, rake face 61 leaves to tilt downwards relative to datum line S1a described later along with from the first cutting edge 5a.Be preferably, tilt angle alpha 2 is such as set as 5 ~ 30 °.

Erect face 62 and mainly play effect by making the track of the chip of nuzzling up on rake face 61 make upward chip curling.As shown in Figure 6, erect face 62 be adjacent to arrange with the rear end side of rake face 61 and along with towards rear end side, tilt upward with tilt angle alpha 3 relative to datum line S1a described later.Be preferably, tilt angle alpha 3 is such as set as 9 ~ 35 °.

In the present embodiment, with regard to erecting the border in face 62 and rake face 61, as shown in Fig. 3 (b), when top view, with by the central 5af of the first cutting edge 5a and the distance of the straight line X ' orthogonal with imaginary line X be set to, along with the part at rear from the central 5af being positioned at the first cutting edge 5a is left and becomes large.That is, the distance on vertical with the tangent line of the central 5af of the first cutting edge 5a direction has such relation.

In addition, as shown in Fig. 3 (b), when top view, erect face 62 along the length on the direction of imaginary line X along with from be positioned at the first cutting edge 5a central 5af rear part towards be positioned at the first cutting edge 5a two ends rear part and diminish.

It should be noted that, as shown in Figure 2, when observing from the side, namely observing from inner surface 12b, erecting can being set at least partially of face 62 more high-order than the first cutting edge 5a.

In addition, be preferably, the tilt angle alpha 2 of rake face 61 is less than the tilt angle alpha 3 in the face of erecting 62.

As mentioned above, as shown in Figure 1, side 4 is connected with upper surface 2 and lower surface 3.In the present embodiment, as shown in figs.5 and 6, side 4 tilts to the inside along with from the side of upper surface 2 towards the side of lower surface 3, and plays as avoiding the effect with the rear knife face of the contact being cut part.

As shown in Figure 1, lower surface 3 is positioned at the opposition side of upper surface 2 across side 4.In the present embodiment, as shown in figs.5 and 6, lower surface 3 also tilts to the inside along with from the side of upper surface 2 towards the side of lower surface 3, and plays as avoiding the effect with the rear knife face of the contact being cut part.In the present embodiment, lower surface 3 in plane, and extends towards adjacent cutting portion.And as shown in Figure 9, lower surface 3 becomes the position contacted with cutter holder 21 when being fixed on cutter holder 21 by edge cutter 1.

(about fixed part)

Fixed part 1b is the position of mainly playing for edge cutter 1 being fixed on the effect on cutter holder, as shown in Figure 1 and Figure 2, and the region between three the cutting portion 1a in leg-of-mutton bight laying respectively at edge cutter 1.In other words, fixed part 1b is positioned at the rear end side of each cutting portion 1a.

As shown in Figure 1 and Figure 2, fixed part 1b has: with the side 4 continuous print outer surface 11b of cutting portion 1a, the inner surface 12b being positioned at the opposition side of outer surface 11b.In the present embodiment, as shown in Figure 9, when being fixed on cutter holder 21 by edge cutter 1, the inner surface 12b of fixed part 1b connects with cutter holder 21.In addition, the face that the lower surface 3 of cutting portion 1a extends also is connected with cutter holder 21.

In addition, as shown in Figure 1, fixed part 1b has through hole 8 through on the direction substantially vertical with outer surface 11b.

When such edge cutter 1 is fixed on cutter holder, as described later, undertaken by the through hole 8 screw inserted between through outer surface 11b and inner surface 12b.

< cutting element >

Next, with reference to Fig. 9, Figure 10, the cutting element 20 involved by one embodiment of the present invention is described in detail.

As shown in Fig. 9,10, the cutting element 20 involved by present embodiment possesses edge cutter 1, is provided with the cutter holder 21 of edge cutter 1 in leading section.

Edge cutter 1 is arranged on cutter holder 21 from the mode that the front end of cutter holder 21 is outstanding with its cutting edge 5.

In the present embodiment, inlay cutter 1 to being fitted through of cutter holder 21, the through hole 8 of screw 22 from edge cutter 1 to be inserted in the screwed hole be arranged at cutter holder 21 and to carry out.By being regulated restraining force by screw 22, edge cutter 1 is pressed into row constraint of going forward side by side.

It should be noted that, also the installation method of present embodiment can be replaced, by following mode, edge cutter is arranged on cutter holder, such as, edge cutter offers hole, by the effect of the lever of substantially l-shaped bar, from the mode that the hole inwall of edge cutter retrains edge cutter, or, use the pin of axle portion and head bias, utilize the hole offered at edge cutter and to the mode etc. of inlaying cutter and retraining.

The manufacture method > of < machining thing

Next, enumerate and edge cutter 1 is installed and carries out the situation of grooving processing, utilize the manufacture method of Figure 11 to the machining thing of embodiments of the present invention to be described.

The manufacture method of the machining thing involved by present embodiment utilizing cutting element 20 to carry out possesses the operation of following (i) ~ (iii).

I (), as shown in Figure 11 (a), makes to be cut the operation that part 100 rotates along arrow A direction.

(ii) as shown in Figure 11 (b), make cutting element 20 in the direction of arrowb along the shape movement being cut part 100, make the cutting edge 5 of cutting element 20 with rotate be cut the operation that part 100 contacts.Cut (grooving processing) being cut part 100 thus.

(iii) as shown in Figure 11 (c), cutting element 20 is moved upward in arrow C side, and make cutting element 20 from the operation being cut part 100 and leaving.

As above cutting being cut part 100 to operation by being set to, desired machining thing can be obtained.

It should be noted that, in the operation of (i), be cut part 100 relative with cutting element 20 close, such as, also can make to be cut part 100 close to cutting element 20.In the same manner, in the operation of (iii), make to be cut that part 100 is relative with cutting element 20 to be left, such as, also can make to be cut part 100 and leave from cutting element 20.

In addition, when continuing machining, as long as keep the state making to be cut part 100 rotation, repeatedly carry out the operation that the cutting edge 5 of cutting element 20 is contacted with the different parts being cut part 100.

In addition, the mode that cutter 1 takes triangle to use as mentioned above is inlayed.Therefore, when the cutting edge 5 of cutting portion used weares and teares, as long as use other the cutting edge 5 of cutting portion untapped.

Above, some embodiments involved in the present invention are illustrated, but the present invention is not limited to these embodiments, in the scope described in claims, can various improvement, change be carried out.

Such as, edge cutter involved by above-mentioned embodiment is that cutter inlayed by through hole through so-called longitudinal type between the second cutting edge continuous print outer surface and inner surface of cutting portion, but, replace it, as shown in figure 12, the edge cutter of so-called horizontal arrangement type can also be applied.

Specifically, if be set to make the upper surface of three cutting portion 1a towards equidirectional formed and through hole 8 from the upper surface side of cutting portion 1a to the through structure of lower face side.Thus, when being arranged on cutter holder by edge cutter, edge cutter being positioned in the upper surface of cutter holder, being inserted by screw and be fixed from through hole 8 towards the lower face side of cutter holder, this through hole 8 is through to lower face side from the upper surface side of the cutting portion 1a of edge cutter.

In this case, it is identical with above-mentioned edge cutter by the structure of cutting portion 1a is set to, for in chip, the position generated near the two ends of the first cutting edge, also can make this position constriction in the direction of the width at the wide width part in chip breaking portion by rake face, and make this position curling for path by the face that erects in chip breaking portion.Therefore, excellent discharge can be played to the chip that the first cutting edge by curve shape convex laterally generates.In this edge cutter 1, three cutting portion 1a with the center of through hole 8 for axle Rotational Symmetry.

In addition, in the above-described embodiment, at upper surface, cutting edge is provided with land, but, replace it, also can be set to the structure that land is not set.Now, as long as be set to rake face and the such continuously structure of the first cutting edge.Thereby, it is possible to reduce cutting resistance further.

Symbol description

1 cutting insert

1a cutting portion

1af front end

2 upper surfaces

3 lower surfaces

4 sides

5 cutting edges

5a first cutting edge

5af central authorities

5b second cutting edge

6 chip breaking portions

61 rake faces

62 erect face

6W wide width part

6L lowest part

6H highest portion

7 lands

1b fixed part

11b outer surface

12b inner surface (mounting surface)

8 through holes

20 cutting elements

21 cutter holders

213 cutter holder lower surfaces

22 screws

100 are cut part

The face (datum level) that S1a is parallel with cutter holder lower surface

Claims

1. a cutting insert, it possesses:

Cutting portion, it has the cutting edge in upper surface, lower surface, the side be connected with described upper surface and described lower surface and the intersection portion that is positioned at described upper surface and described side; And

Fixed part, it is positioned at the rear end side of described cutting portion when carrying out top view to described cutting portion,

When top view, described cutting edge has: be positioned at the front of described cutting portion and the first cutting edge of circular shape convex laterally; And a pair second cutting edges of the rectilinear form to be connected respectively with the two ends of described first cutting edge,

Described upper surface has chip breaking portion, and described chip breaking portion has: be positioned at described first cutting edge inner side and along with the rake face tilted downwards towards inner side; And be disposed adjacent and the face that erects tilted upward along with the rear end side towards described cutting portion in the rear end side of described cutting portion relative to described rake face,

When top view, described chip breaking portion leans on the rear end side of described cutting portion to have wide width part at the two ends than described first cutting edge, and the width of described wide width part on the direction orthogonal with the imaginary line extended from the rear end side of described cutting portion towards front is maximum.

2. cutting insert according to claim 1, wherein,

When top view, the length along the described chip breaking portion on the direction of described imaginary line is positioned at the part of the rear end side of described cutting portion along with the part being positioned at the rear end side of described cutting portion from the central authorities relative to described first cutting edge towards the two ends relative to described first cutting edge and diminishes.

3. cutting insert according to claim 1 and 2, wherein,

When top view, described chip breaking portion the straight line parallel with described imaginary line has a position of lowest order by the central authorities of described first cutting edge.

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

When top view, described chip breaking portion the straight line parallel with described imaginary line has a position of highest order by the central authorities of described first cutting edge.

5. the cutting insert according to any one of Claims 1 to 4, wherein,

When top view, described a pair second cutting edges are not parallel each other.

6. the cutting insert according to any one of Claims 1 to 5, wherein,

Described fixed part has through hole, and described through hole is relative to through on the direction substantially vertical with described a pair second cutting edge continuous print sides.

7. the cutting insert according to any one of claim 1 ~ 6, wherein,

When top view, described in erect face and described rake face border in towards the convex curve shape of the central authorities of described first cutting edge.

8. the cutting insert according to any one of claim 1 ~ 7, wherein,

When top view, the length erecting face described on the direction of described imaginary line is positioned at the part of the rear end side of described cutting portion along with the part being positioned at the rear end side of described cutting portion from the central authorities relative to described first cutting edge towards the two ends relative to described first cutting edge and diminishes.

9. the cutting insert according to any one of claim 1 ~ 8, wherein,

When observing from the side, described in erect the higher than described first cutting edge at least partially of face.

10. the cutting insert according to any one of claim 1 ~ 9, wherein,

The angle of inclination erecting face described in the angle of inclination ratio of described rake face is little.

11. cutting inserts according to any one of claim 1 ~ 10, wherein,

Described upper surface also has the land between described first cutting edge and described chip breaking portion.

12. cutting inserts according to claim 11, wherein,

When top view, the interval between described first cutting edge and described chip breaking portion and the length of described land are the shortest with the continuous print part place, front end of described first cutting edge.

13. cutting inserts according to claim 11 or 12, wherein,

Described land tilts downwards along with leaving from described first cutting edge.

14. cutting inserts according to claim 13, wherein,

The angle of inclination of described land is less than the angle of inclination of described rake face.

15. 1 kinds of cutting elements, it possesses:

Cutting insert according to any one of claim 1 ~ 14; And

The cutter holder of described cutting insert is installed in leading section.

The manufacture method of 16. 1 kinds of machining things, it comprises:

Make the operation being cut part rotation;

Make the operation that the described cutting edge being cut the described cutting element that part is recorded with claim 15 described in rotation contacts; And

The operation that part leaves from described cutting element is cut described in making.