JP5528135B2 - Cutting insert - Google Patents

Description

  The present invention relates to a cutting insert.

  Conventionally, as a cutting insert used for a turning tool such as a face mill or an end mill, a cutting insert in which a flank including a cutting edge is divided by a groove is known (for example, Patent Document 1). In such a cutting insert, since the cutting edge is divided by the groove portion, the cutting resistance during cutting is reduced. And this cutting insert has such a division | segmentation cutting edge in each edge | side from a viewpoint of economical efficiency.

  However, when there are divided cutting edges on each of such adjacent sides, narrow chips generated from the divided cutting edge corresponding to one side are clogged in a groove formed on the other adjacent side, and cutting is performed. There is a risk of damaging the insert itself, the holder fitted with the cutting insert, or the machined surface.

JP-A-9-57519

  An object of the present invention is to provide a cutting insert having a low cutting resistance and excellent chip discharge performance.

A cutting insert according to an embodiment of the present invention includes a main body having a first side surface, a second side surface adjacent to the first side surface, and an upper surface and a lower surface intersecting the first side surface and the second side surface. The first side surface includes a plurality of groove portions reaching the upper surface, and a split cutting edge formed at the intersection line with the upper surface and divided by the plurality of groove portions, and the second side surface. The side surface has a non-divided cutting edge formed at the intersection with the upper surface, and the upper surface includes a rake face provided along the divided cutting edge and the non-divided cutting edge, and an inner side than the rake face. And a plurality of first convex portions provided respectively corresponding to the plurality of groove portions, and the divided cutting surfaces. The virtual extension line of the blade and the virtual extension line of the non-divided cutting edge Having a second projecting portion which passes through the bisector of the angle formed between.

  A cutting tool according to an embodiment of the present invention includes a holder having a plurality of insert pockets on an outer peripheral surface on a front end side, and the cutting inserts mounted on the insert pockets, respectively, and the divided cutting blade and the non-divided cutting blade. The cutting insert is mounted so that the blades alternately protrude outward from the outer peripheral portion on the tip end side of the holder.

  A cutting method of a work material according to an embodiment of the present invention is a method using the above cutting tool, the step of rotating the cutting tool, and at least of the plurality of divided cutting blades of the rotating cutting tool A step of bringing a part into contact with the surface of the work material, and a step of separating the work material from the cutting tool.

According to the cutting insert of the present invention, the non-divided cutting edge is formed on the second side surface adjacent to the first side surface on which the divided cutting edge is formed. Therefore, when using a division | segmentation cutting blade for cutting, the deterioration of the chip | tip discharge property by a chip | tip clogging in the groove part formed in the adjacent side surface can be reduced. Further, when the non-divided cutting edge is used for cutting, the angle between the first convex portion provided corresponding to the groove, the virtual extension line of the divided cutting edge, and the virtual extension line of the non-divided cutting edge is The second convex portion provided on the bisector prevents the chips generated by the non-divided cutting blade from proceeding to the first side surface, and reduces the clogging of the chips formed in the groove formed on the first side surface. Is done. Therefore, excellent chip dischargeability is obtained.

It is a perspective view showing an example of a cutting insert according to an embodiment of the present invention. It is a top view of the cutting insert shown in FIG. It is the side view which looked at the cutting insert shown in FIG. 2 from the X direction. It is the side view which looked at the cutting insert shown in FIG. 3 from the Y direction. It is sectional drawing in the AA of the cutting insert shown in FIG. 1 is an overall perspective view showing a cutting tool according to an embodiment of the present invention. It is process drawing explaining the manufacturing method of the workpiece according to one Embodiment of this invention.

<Cutting insert>
Hereinafter, a cutting insert 1 (hereinafter simply referred to as an insert 1) according to an embodiment of the present invention will be described with reference to FIGS.

  A cutting insert 1 according to an embodiment of the present invention includes a first side surface 2a, a second side surface 2b adjacent to the first side surface 2a, and an upper surface 3 and a lower surface 4 that intersect the first side surface 2a and the second side surface 2b. And a main body having Specifically, the main body portion is substantially plate-shaped, and when viewed from above, it may be a quadrangle or more, specifically a quadrangle, a pentagon, a hexagon, an octagon, etc. That's fine. In this embodiment, the main body has a substantially quadrangular shape having four long sides and four corners having the same length. A cutting edge is provided at the intersection of the first side surface 2 a and the second side surface 2 b and the upper surface 3.

Specifically, the main body part intersects so that the angle formed by the side surface 2 (the first side surface 2a and the second side surface 2b) and the upper surface 3 is an acute angle. That is, as shown in FIG. 2B, the insert 1 is a so-called positive type insert having a side surface provided with a positive clearance angle θ. Here, the clearance angle θ is an inclination angle of the side surface 2 with respect to an auxiliary line substantially perpendicular to the lower surface 4 in a side view. In the present embodiment, the clearance angle θ is constant in a region along the cutting edge 4.
The insert 1 of the present invention may be a so-called negative type insert in which the side surface 2 is formed perpendicular to the upper surface 3 and the lower surface 4 from the viewpoint of the strength of the insert.

  A groove 5 is provided on the first side surface 2a. The groove 5 is provided so as to divide the cutting edge 6 into a plurality of divided cutting edges 61. That is, as shown in FIGS. 1 and 2, one end of the groove 5 reaches the upper surface 3. Further, as shown in FIG. 2A, the groove 5 is formed to have a concave shape that opens outward in a top view. The groove 5 may or may not reach the lower surface 4 side end. In the present embodiment, the groove portion 5 has a shape that does not reach the end portion on the side of the lower surface 4 in a side view from the viewpoint of suppressing a decrease in strength of the insert 1.

  In the present embodiment, one cutting blade 6 is divided into eight divided cutting blades 6a by seven groove portions 5, and a plurality of generated chips are also small in width. Therefore, the load applied to the insert during cutting is reduced. As a result, excellent cutting performance can be exhibited even under cutting conditions where the cutting load is higher or the cutting speed is higher.

  The second side surface 2b has a non-divided cutting edge 6b formed at the intersection line with the upper surface 3. In the present embodiment, the first side surface 2a having the divided cutting edge 6a and the second side surface 2b having the non-divided cutting edge 6b are formed adjacent to each other as described above. Thus, since the groove part is not formed in the side surface (2nd side surface 2b) adjacent to the 1st side surface 2a which has the division | segmentation cutting edge 6a, when cutting with the division | segmentation cutting edge 6a which had arisen conventionally, it is adjacent. Damage to the insert, the holder, or the processing surface is reduced by clogging the grooves formed in the mating side surfaces. In addition, since the chip | tip produced | generated from the non-dividing cutting blade 6b is wider than the groove part 5, it is less likely to clog a groove part.

  In the present embodiment, specifically, the second side surface 2b is disposed on both sides of the first side surface 2a. That is, in this embodiment, it is comprised by four side surfaces, and the 1st side surface 2a and the 2nd side surface 2b are arrange | positioned alternately.

  On the upper surface 3, a rake surface extending inwardly from the cutting edge 6 along the cutting edge 6 (the divided cutting edge 6 a and the non-dividing cutting edge 6 b), and an inward position from the rake face. A breaker surface is provided so as to be positioned higher as the distance increases. From the viewpoint of reducing cutting resistance, the rake face is provided so as to be positioned at a lower position as the distance from the cutting edge 6 increases. The breaker surface is inclined so as to be positioned higher as it goes inward. The breaker surface is disposed to face the divided cutting edge 6a. With such a configuration, it is possible to stably further curl the chips with the breaker surface generated by the divided cutting blade 6a and curled along the rake face, and cut the chips in the length direction.

A first protrusion 71 is provided on the upper surface 3 corresponding to the groove 5. Here, “the first convex portion 71 corresponds to the groove portion 5” means that the first convex portion 71 is arranged on the upper surface 3 so as to satisfy the following two points.
The first convex portion 71 is positioned inward of the groove portion 5 on the upper surface 3.
-At least one part of the 1st convex part 71 is located on the virtual straight line along the direction where the groove part 5 extends through the center in the width direction of the groove part 5. As shown in FIG.

  In this embodiment, the 1st convex part 71 is formed along the said virtual straight line. That is, it is an upper surface and is located in an extended region that passes when the groove 5 is extended in the longitudinal direction.

  In addition, inward here means the direction which goes to the center side of the insert 1 with respect to the cutting blade 4 by the top view.

  The insert 1 of the present embodiment stabilizes the discharge direction of the chips so that the short chips generated by the adjacent divided cutting edges 6a do not collide with each other by the first convex portion 71 having such a configuration. Can do. For this reason, it is possible to suppress damage to the cutting blade and the holder, deterioration of the processing surface of the work material, deterioration of processing accuracy, and the like due to the chips being caught between the cutting blade and the work material.

That is, the chips generated by the divided cutting blade 6a are curled along a rake face extending inward from the divided cutting blade 6a. In that case, the 1st convex part 71 is provided in the inside of the groove part 5, ie, the direction where chips are discharged | emitted with respect to the groove part 5. As shown in FIG. By this first convex portion 71, it is possible to suppress the discharge direction of the chips finely divided in the width direction from swinging left and right. Therefore, the chips generated by the divided cutting blade 6a are prevented from colliding with each other. As a result, excellent chip discharge performance can be exhibited.

  In particular, even in a cutting mode in which a large load is applied at the time of cutting, such as intermittent cutting or high feed processing, it is possible to exhibit excellent chip discharging performance while reducing the cutting resistance at the time of cutting.

  In the present embodiment, a plurality of first convex portions 71 are provided corresponding to the plurality of groove portions 5.

  The shape of the 1st convex part 71 should just be a shape which can suppress the blurring of a chip. In the present embodiment, as shown in FIG. 5, the first convex portion 71 is further connected to the front end portion 711 positioned higher as the distance from the groove portion increases, and to the top portion in the direction away from the groove portion. The rear end 712 has a substantially constant height position.

  In the present embodiment, the front end portion 711 increases in width as the distance from the groove portion 5 increases, and is provided so as to protrude from the corresponding groove portion 5 toward the divided cutting edge 6a. That is, the width W711 of the front end portion 711 of the first convex portion is larger than the width W5 of the groove portion 5 in a top view. With such a configuration, the chips generated by the divided cutting blade 6a are first curled along a rake face extending inward from the divided cutting blade 6a. In that case, the edge part of a chip contacts the front-end part 711, and a chip is deform | transformed so that the cross-sectional shape of a chip may become concave shape. Therefore, the width of the chips generated by the divided cutting blade 6a can be gradually reduced as the chips are curled along the rake face. As a result, the effect of suppressing adjacent chips from colliding with each other is enhanced.

  The width W711 of the front end portion 711 here is the maximum value among the dimensions in the direction along the divided cutting edge 6a in a top view.

  The width W5 of the groove 5 is the distance between two intersections between the virtual extension line of the wall surface of the groove 5 and the virtual extension line of the cutting edge 411. FIG. 2 illustrates the width W5 of the groove 5. Here, the wall surface of the groove portion 5 refers to a series of surfaces connected to the rake face and the side surface 2. In addition, unlike the present embodiment in which the wall surface of the groove portion 5 has a flat surface, when the entire wall surface of the groove portion 5 is configured by a curved surface, the tangent line of the curved surface may be a virtual extension line of the wall surface of the groove portion described above. . In the present embodiment, the width of the rear end portion becomes narrower as the distance from the groove portion increases.

  The first convex portion 71 is positioned higher than the divided cutting edge 6a. With such a configuration, the collision between chips is further suppressed.

  The rear end 712 extends inward from the groove and is formed so as to partition the breaker surface. With such a configuration, it is further reduced that chips generated from adjacent divided cutting blades collide with each other.

  The arrangement of the first protrusions 71 is not particularly limited as long as it is arranged so as to correspond to each groove. From the viewpoint of further stabilizing the chip discharge direction, it is preferable that the chip is formed at a position close to the groove. Moreover, in this embodiment, the 1st convex part 71 is arrange | positioned ranging over a rake face and a breaker surface. With such a configuration, it is possible to suppress chip blurring for a longer time.

On the upper surface 3, a second convex portion 72 is provided on a bisector of an angle formed by the virtual extension line of the divided cutting edge 6a and the virtual extension line of the non-divided cutting edge 6b. This 2nd convex part is provided in order to suppress that the chip | tip produced | generated from the division | segmentation cutting edge 6a goes to the non-division | segmentation cutting edge 6b side. In this embodiment, the 2nd convex part 72 is substituted by the said 1st convex part nearest to the 2nd side surface side. Thus, the 2nd convex part 72 may be integrated with the 1st convex part 72 in the range which does not impair the effect of this invention.

  In the present embodiment, the protruding portion 8 is disposed inward of the divided cutting edge 6a, that is, at a position corresponding to the space between the first convex portions and in the vicinity of the top portion of the breaker surface.

  The insert 2 </ b> A has a through hole 9 that penetrates from the center of the upper surface 3 to the center of the lower surface 4. The through-hole 9 is a hole through which an attachment screw is inserted for attachment to the holder. The four cutting edges 6 are arranged so as to be 90-degree rotationally symmetric about the axis of the through hole 9.

  In the insert 1 in the present embodiment, a non-divided cutting edge in which no groove is formed is provided on the second side surface adjacent to the first side surface on which the divided cutting edge is formed. Therefore, when using a division | segmentation cutting blade for cutting, the deterioration of the chip | tip discharge | emission property that a chip | tip clogs in the groove part formed in the adjacent side surface can be reduced. Further, when the non-divided cutting edge is used for cutting, the angle between the first convex portion provided corresponding to the groove, the virtual extension line of the divided cutting edge, and the virtual extension line of the non-divided cutting edge is The second convex portion provided on the bisector prevents the chips generated by the non-divided cutting blade from proceeding to the first side surface, and reduces the clogging of the chips formed in the groove formed on the first side surface. Is done. Therefore, the insert 1 in the present embodiment has excellent chip discharging properties.

<Cutting tools>
A cutting tool 20 according to an embodiment of the present invention includes a holder 10 having a plurality of insert pockets 11 on the outer peripheral surface on the front end side, and the cutting inserts 1 mounted in the insert pockets 11 respectively.

  The holder 10 has a substantially rotating body shape with the axis S as the center. Four insert pockets 11 are provided on the outer peripheral surface on the tip end side of the holder 10. The insert pocket 11 is a portion to which the insert 1 is mounted, and is open on the outer peripheral surface and the front end surface of the holder 10.

  And the cutting insert 1 is mounted | worn corresponding to the some insert pocket 11 provided in the holder 10. FIG. The plurality of inserts 1 are mounted such that the cutting edge 6 protrudes outward from the outer peripheral surface. At this time, the insert 1 mounted so that the divided cutting blade 6a protrudes from the outer peripheral surface and the insert 1 mounted so as to protrude the non-divided cutting blade 6b outward from the outer peripheral surface are alternately arranged. It is preferable. Further, the processed surface processed by the divided cutting edge 6a has a groove-shaped uncut portion. In the present embodiment, since the insert 1 in which the non-divided cutting edge 6b protrudes outward is provided at the rear of the holder 10 in the rotation direction, the uncut portion of the groove-like processed surface can be reliably cut. It is possible to obtain a flatter processed surface without a step.

  In the present embodiment, the insert 1 is mounted in the insert pocket 11 with a fixing screw. That is, the insert 1 is mounted on the holder 1 by inserting a fixing screw into the through hole 9 of the insert 1 and screwing the tip of the fixing screw into a screw hole (not shown) formed in the insert pocket 11.

Furthermore, in the present embodiment, the insert 1 is mounted on the holder 10 so that the cutting edge protruding outward from the outer peripheral surface has a positive axial rake angle. That is, as shown in FIG. 4 to be described later, the cutting edge 6 of the insert 1 arranged on the outer peripheral surface side of the holder 10 in a side view is the axis of the holder 10 as it goes from the front end side to the rear end side of the holder 10. Inclined away from S. With such a configuration, it is possible to reduce the cutting resistance applied during cutting.

<Cutting method of work material>
The cutting method of the work material which concerns on one Embodiment of this invention using FIG. 5 demonstrates the case where the cutting tool 20 is used as an example. A cutting method for a work material according to the present embodiment includes the following steps (i) to (iii).
(I) As shown in FIG. 5A, the cutting tool 20 is rotated in the direction of arrow A around the axis S of the holder 10, moved in the direction of arrow B, and the cutting edge of the cutting tool 10 is placed on the work material 100. The process of approaching.
(Ii) As shown in FIG. 5B, the cutting blade 6 of the insert 1 is brought into contact with the surface of the work material 100, the cutting tool 20 is moved in the direction of arrow C, and the surface of the work material 100 is cut. .
(Iii) A step of moving the cutting tool 20 in the direction of arrow D to separate the cutting tool 20 from the work material 100 as shown in FIG.

  Thereby, as mentioned above, since it processes using the cutting tool 10 which is provided with the outstanding chip discharge | emission property and can obtain a smoother processed surface, improvement of processing efficiency and finished surface precision can be aimed at.

  The cutting tool 20 and the work material 100 may be relatively close to each other. For example, the work material 100 may be close to the cutting tool 20. Similarly, in the step (iii), the work material 100 and the cutting tool 20 need only be relatively distant from each other. For example, the work material 100 may be kept away from the cutting tool 20. In the case of continuing the cutting process, the process of rotating the cutting tool 20 and holding the cutting blade 6 of the insert 1 in contact with different parts of the work material 100 may be repeated. When the cutting edge 6 being used is worn, the insert 1 may be rotated 90 degrees with respect to the central axis of the through hole 9 and the unused cutting edge 6 may be used.

  As mentioned above, although some embodiment which concerns on this invention was illustrated, this invention is not limited to embodiment mentioned above, It cannot be overemphasized that it can be made arbitrary, unless it deviates from the objective of invention. Absent.

DESCRIPTION OF SYMBOLS 1 Cutting insert 2a 1st side surface 2b 2nd side surface 3 Upper surface 4 Lower surface 5 Groove part 6a Divided cutting blade 6b Non-divided cutting blade 71 1st protruding part 72 2nd protruding part 8 Protrusion part 9 Through hole 10 Holder 20 Cutting tool 100 Workpiece Material

Claims (11)

A main body having a first side surface, a second side surface adjacent to the first side surface, and an upper surface and a lower surface intersecting the first side surface and the second side surface;
The first side surface includes a plurality of groove portions reaching the upper surface, and a split cutting edge that is formed at a line of intersection with the upper surface and divided by the plurality of groove portions,
The second side surface has a non-divided cutting blade formed at the intersection with the upper surface,
The upper surface is positioned inward of the rake face provided along the divided cutting edge and the non-divided cutting edge, and is positioned higher as the distance from the divided cutting edge and the non-divided cutting edge increases. a breaker surface as said plurality of first convex portions of a plurality provided corresponding to the groove, second-in angle between the virtual extension of the virtual extension line and the undivided cutting edge of the divided cutting edge A cutting insert having a second convex portion passing on the segment. First projection before SL are arranged across the rake face and the breaker face, the cutting insert according to claim 1. Said first convex portion close most to the side of the second side surface, and the second convex portions are integrated, the cutting insert according to claim 1 or 2. The said main-body part has multiple said 1st side surfaces and said 2nd side surfaces , respectively, The said 1st side surface and the said 2nd side surface are arrange | positioned alternately, The statement in any one of Claim 1 to 3 Cutting inserts. In a position corresponding to between before Symbol said even on the breaker face first protrusion, the protrusion is arranged, the cutting insert according to any one of claims 1 4.   The first convex portion has a front end portion that is positioned higher as it is separated from the groove portion, and a rear end portion that is connected to the front end portion and is positioned lower as it is separated from the groove portion. The cutting insert according to any of the above items. The cutting insert according to claim 6 , wherein the front end portion becomes wider as the distance from the groove portion increases. The cutting insert according to claim 6 or 7 , wherein a width of the rear end portion becomes narrower as the distance from the groove portion increases. A holder having a plurality of insert pockets on the outer peripheral surface on the front end side, and the cutting insert according to any one of claims 1 to 8 mounted in each of the insert pockets,
The cutting tool with which the said cutting insert is mounted | worn so that the said division | segmentation cutting edge and the said non-dividing cutting edge may protrude outward from the front end side outer peripheral part of the said holder alternately.   The cutting tool according to claim 9, wherein the cutting insert is attached to the holder so that the divided cutting blade and the non-divided cutting blade each have a positive axial rake. A method of cutting a work material using the cutting tool according to claim 9 or 10,
Rotating the cutting tool;
Contacting at least a part of the plurality of divided cutting blades of the rotating cutting tool with the surface of the work material;
Separating the work material and the cutting tool;
A method for cutting a work material.

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