JP5343600B2 - Cutting insert - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cutting insert capable of appropriately treating cutting chips, even if working conditions such as a type, a cut amount, and feed speed of a material to be cut vary, by locking a tip of a cut chip on a flank to restrain its movement. <P>SOLUTION: In the cutting insert, front and rear faces of a flat plate-like insert body 1 are made into rake faces 2, and a peripheral side face of the insert body 1 is made into the flank 3. A cutting edge 4 is formed at an intersection ridge of the rake faces and the flank along a circumference of the rake faces. A plurality of at least one of uneven parts, protrusions and recesses are successively formed on the flank without forming flat areas between them. The cut chip W made by the cutting edge has its tip locked with a locking recess or a locking protrusion on the flank, thereby restraining further movement of the tip. Thus, strong bending force or shear force works to the spiral or arcuate cut chip W, which is split as a result. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a cutting insert that is attached to an insert detachable turning tool and can reliably process chips even in light cutting from a medium cutting with a relatively large cutting amount to a finishing cutting with a small cutting amount. It is.

As a cutting insert using a rake face that enables chip disposal over a wide range from such medium cutting to finish cutting, for example, in Patent Document 1 below, a breaker groove along the cutting edge is formed on the rake face. In addition, the protrusion of the boss surface is extended to the corner part of the cutting edge, and the tip of the protrusion is formed into a concave shape surrounding the corner part in a plan view, and is projected to the vicinity of the cutting edge from the two tops of the protrusions exhibiting this concave shape. An upright surface having an upright angle of 10 ° to 30 ° is formed, and the upright surface is formed so as to be farther from the cutting edge as it is away from the corner portion.
In the cutting insert described in Patent Document 1, the upright surface protrudes from the two tops of the protrusions to the rake face near the cutting edge, so the protrusion height from the top to the top of the protrusion and the distance from the top to the cutting edge. Depending on the type, the slope of the rising surface becomes steep and it becomes difficult to form the rising angle as described above. There is a problem that the life is shortened. On the other hand, if the protrusion height to the top of the protrusion itself is made small in order to make the standing angle within the above range, the chips generated in the finishing cutting with a small cutting depth will flow over the protrusion and flow out, and smooth chip disposal There is a defect that damages

As another method of chip disposal in the cutting insert, the tip of the chip is pressed against the flank formed on the side surface of the cutting insert to restrain the movement of the chip tip, thereby applying shearing force or bending force to the chip. What is divided is known.
In addition, in the following Patent Document 2, for the purpose of improving the heat dissipation effect rather than the chip disposal, a plurality of concave portions are arranged vertically and horizontally on the flank face of the side surface of the cutting insert while being spaced apart from each other. Yes.

JP 2006-272548 A International Publication No. 2004-050314 Pamphlet

In the cutting insert described in Patent Document 2, the concave portions formed on the side flank are arranged with a space between each other, and a good heat dissipation effect can be obtained by increasing the side surface area. There existed a subject that chip disposal cannot be performed favorably.
That, in the said cutting insert, a recessed portion is disposed apart Oh only with each other, the flat portion therebetween recess is formed. For this reason, when the tip of the chip first hits the bottom of the recess on the flank, the tip of the chip can be locked, but the processing conditions such as the cutting amount and feed rate change, and when the tip of the chip hits a flat part, The tip of the chip slides on the flat part and moves, and the movement of the tip of the chip cannot be restricted. In this case, there is a problem that not only the cutting of the chips can be performed, but also the flank functions as a guide for discharging the chips and promotes the long and stable growth of the chips.

  The present invention was made under such a background, and by locking the tip of the chip to the flank and restraining its movement, the processing conditions such as the type of workpiece, the amount of cutting, and the feed rate Provided is a cutting insert capable of suitably performing chip disposal even when changes occur.

In order to solve the above-described problems, the present invention provides at least one of the front and back surfaces of a polygonal flat plate-like insert body as a rake face, and the peripheral side surface of the insert body as a flank face. In a cutting insert that is a peripheral edge and has a cutting edge formed at a crossing ridge line portion between the rake face and the flank face, a guide part that guides the tip of the swarf to the flank face while curling the chips on the rake face. The flank has a concavo-convex shape formed continuously and vertically and horizontally . That is, in the present invention, the concavo-convex shape formed on the flank is continuously formed in the vertical and horizontal directions, and a flat portion that is a surface portion before processing of the flank is not formed between the concavo-convex shapes . Further, the unevenness formed on the flank does not necessarily need to be formed over the entire flank, and may be formed only on a portion of the flank that is likely to hit the tip of chips.

  In the cutting insert configured as described above, chips generated by the cutting blade extend on the rake face while being curled during medium cutting with a relatively large cutting depth. Chips at the time of medium cutting often have large thickness and relatively high rigidity, so that they are often broken and broken when curled.

On the other hand, in the case of finish cutting with a small depth of cut, the chips generated by the cutting blade have a small thickness and a relatively low rigidity. For this reason, even if it curls, it does not break easily and tends to extend like a spiral. The chips extend while drawing a large arc while being curled, and the tip of the chips hits the flank of the cutting insert. In this case, an uneven shape is continuously formed on the flank. For this reason, the tip of the chip is locked to the locking concave portion or the locking convex portion that forms the concavo-convex shape of the flank, and the chip whose tip is locked is further restrained from moving on the tip side. The As a result, a strong bending force or shearing force acts on the spiral or arcuate chips, resulting in fragmentation.

In the cutting insert of the present invention, it is preferable that the concavo-convex shape formed on the flank is formed continuously in the vertical and horizontal directions along the thickness direction of the insert body and the circumferential direction orthogonal to the thickness direction. .
In this case, when the tip of the chip moves on the flank in the direction intersecting the thickness direction of the insert body and the circumferential direction perpendicular to the thickness direction, the locking formed on the surface of the flank As a result, the tip ends of the chips are engaged with any one of the locking recesses that overlap and overlap each other in the moving direction. It becomes easy to be stopped.

In the cutting insert of the present invention, the concavo-convex shape formed on the flank is formed in a row in the vertical and horizontal directions along the thickness direction of the insert body and the direction intersecting the circumferential direction orthogonal to the thickness direction. It is preferable.
In this case, when the tip of the chip moves on the flank in the thickness direction of the insert main body or in the circumferential direction perpendicular to the thickness direction, the arrangement direction of the locking recesses formed on the surface of the flank As a result, the tips of the chips are likely to be locked to any of the locking recesses that are overlapped with each other while overlapping each other in the moving direction.

In the cutting insert of the present invention, the guide portion is formed on the rake face inside the cutting blade so as to protrude in the thickness direction of the insert body with a space between the cutting blade and the cutting blade. The protrusion and the corner of the rake face are formed so as to extend from the wall surface of the protrusion to the cutting edge side on both sides of the bisector of the corner. The height is higher than the height of the protrusion It is preferable that it is comprised by a pair of convex part set low .
In this case, during cutting, chips flow out to the inside of the rake face and first contact the wall surface of the convex portion. Then, the chips collide with the wall surface of the protrusion while being guided in sliding contact with the wall surface of the convex portion, are curled by receiving resistance from the wall surface 5B, and the tip thereof is guided to the flank surface . The locked becomes Rukoto tip of該切debris on the flank surface formed uneven, consequently, the chips are separated.

A concavity formed on the rake face of the insert body may be a pyramidal shape such as a quadrangular pyramid or a hexagonal pyramid, or a truncated pyramid shape such as a quadrangular pyramid or a hexagonal pyramid.
In addition, although a cone or a truncated cone shape is also conceivable, in order to arrange so that a flat portion is not formed between the concave portions such as the conical shape, the base portion of the concave portion such as the conical shape, It is necessary to make a polygonal shape such as a square or a hexagon, and when one concave portion is seen, the cross-sectional polygonal shape and the cross-sectional circular shape are mixed and the production becomes troublesome.

  As described above, according to the present invention, the tip of the chip can be locked in medium cutting with a relatively large depth of cut, and of course, the tip of the chip can also be locked during finish cutting with a relatively small depth of cut. Then, the movement can be restricted and the chips can be appropriately divided.

FIG. 1 is a perspective view of a cutting insert according to an embodiment of the present invention. FIG. 2 is a plan view of the cutting insert of the same embodiment. FIG. 3 is a front view of the cutting insert of the embodiment. FIG. 4 is an enlarged perspective view of a part of the cutting insert of the same embodiment. FIG. 5 is a perspective view of a cutting insert according to another embodiment of the present invention. FIG. 6 is a perspective view of a cutting insert according to another embodiment of the present invention. FIG. 7 is a perspective view of a cutting insert according to still another embodiment of the present invention.

1 to 4 show an embodiment of the present invention. FIG. 1 is a perspective view of a cutting insert of the embodiment of the present invention, FIG. 2 is a plan view of the cutting insert of the embodiment, and FIG. FIG. 4 is an enlarged perspective view of a part of the cutting insert according to the embodiment.
In the present embodiment, the insert body 1 is formed in a polygonal flat plate shape by a hard material such as a cemented carbide, in particular, a diamond flat plate shape, and a rake face 2 is formed on a pair of upper and lower rhomboid surfaces. The flank 3 disposed around the rake face 2 is a negative type insert extending parallel to the thickness direction of the insert body 1 (vertical direction in FIG. 1). The insert body 1 has the pair of rhombus surfaces symmetrically reversed, and is also 180 ° rotationally symmetric with respect to the center line of the rhombus surface. Further, the acute angle portions of the rhombus and obtuse angles are formed. It is also formed symmetrically on a plane parallel to the thickness direction connecting the corners.

  Then, a cutting edge 4 is formed on the periphery of the rake face 2 which is an intersecting ridge line part of the rake face 2 and the flank face 3. have. In the present embodiment, the corner portion 4A has a convex arc shape in plan view when viewed in the thickness direction, and is formed to extend with a predetermined height in the thickness direction. Further, the cutting edge 4 has a pair of inclined parts 4B extending as tangents to the corner part 4A in the plan view at both ends of the corner part 4A, and the opposite side of the inclined part 4B to the corner part 4A. In the plan view, the straight portion 4C is connected to the inclined portion 4B in a straight line and extends in the thickness direction perpendicularly to the obtuse angle portion of the rhombus.

  As shown also in FIG. 4, on the rake face 2 inside the cutting edge 4 including the corner portion 4A, the cutting edge 4 is spaced apart from the rake face 2 in the thickness direction. A protruding portion 5 is formed. The protrusion 5 is a flat surface perpendicular to the thickness direction, and has a top 5A that protrudes in the thickness direction higher than the cutting edge 4 and a protrusion 7 that will be described later, and toward the top 5A. And a wall surface 5B inclined so as to gradually rise in the thickness direction as it goes inward of the rake face 2, and the top portion 5A penetrates the insert body 1 in the thickness direction at the center of the rake face 2. A mounting hole 6 formed as described above is opened.

  The rake face 2 is a positive rake face 2A in which the portion on the cutting edge 4 side gradually recedes toward the inside in a cross section orthogonal to the cutting edge 4 inside the corner portion 4A. Further, the rake face 2 of the portion of the cutting edge 4 that is continuous with the linear portion 4C, in order from the cutting edge 4 inward, is a negative land portion with a very narrow width that intersects the relief face 3 at an obtuse angle, The positive rake face 2A having a rake angle equal to the positive rake face part on the side of the cutting edge 4 inside the corner part 4A through the narrow flat land part which is wide and extends perpendicularly to the thickness direction, and further A flat rake face 2B that smoothly contacts the wall surface 5B of the protrusion 5 inside the linear part 4C is formed on the inner side.

  In the periphery of the corner portion 4A, from the wall surface 5B of the projection 5 to the rake face 2, a pair of convex portions 7 are formed on both sides of the bisector L of the rhomboid acute angle portion formed by the rake face. It is formed to extend to the side. These convex parts 7 face the corner part 4A side of the cutting edge 4, and are spaced apart from each other toward the cutting edge 4 side from the wall face 5B of the protruding part 5 and extend to the both end parts of the corner part 4A. And a second wall surface 7B that intersects the first wall surface 7A at the intersecting ridge line M and faces the inclined portion 4B side of the cutting edge 4 in opposite directions, and rounds the intersecting ridge line M portion. A beveled chamfer is applied.

  Here, the protruding portion 5 and the convex portion 7 are provided with a guide portion 10 that guides the tip to the flank 3 while curling the chips W even during finishing cutting with a small cutting amount or during medium cutting with a large cutting amount. It is composed.

  On the other hand, a plurality of recesses 11 are arranged on the flank 3 so as to cross obliquely at an appropriate angle (45 degrees in this embodiment) with respect to the thickness direction or the circumferential direction of the cutting insert and vertically and horizontally. It is formed in the state. In this embodiment, two types of recesses 11 are formed. That is, the corner portion of the flank is formed with a locking recess 11A having a pair of triangular inclined surfaces obtained by bending a predetermined angle along a ridge line connecting the vertices of a square, and generally connecting the corner portions. The flat portion is formed with a locking recess 11B having a regular quadrangular pyramid shape. The locking recesses 11A and 11B are continuously formed in close contact with each other without forming a gap therebetween. Therefore, a flat portion that is a surface portion of the flank before processing is not formed between the locking recesses 11A and 11B.

  The size of the locking recesses 11A and 11B is set so that the tip of the chip W can be locked. For example, in the case of the locking recess 11B, the vertical dimension La and the horizontal dimension Lb are set to 0.1 mm to 3.0 mm, and the depth D is set to 0.02 mm to 3.0 mm.

  In addition, as a method of forming the concave portion 11 on the flank 3, for example, a convex portion is formed in advance on the inner surface of a mold for forming the cutting insert, and when the cutting insert is press molded or injection molded, A method of transferring irregularities to the side surface of the main body 1 can be considered. Of course, the concave and convex transfer method using the inner surface of such a mold is not limited, and the concave portion 11 may be formed by machining such as cutting or grinding, and it is conceivable to use electric discharge machining or film formation technology. .

Next, the operation of the cutting insert having the above configuration will be described.
In the case of medium cutting where the cutting depth is relatively large as used from the corner portion 4A of the cutting edge 4 to the inclined portion 4B connected to one end thereof, the chips W generated by the cutting are scooped from the corner portion 4A and the inclined portion 4B. It flows out to the inside of the surface 2 and first comes into contact with the second wall surface 7B of the convex portion 7. The chips W collide with the wall surface 5B of the projection 5 while being guided in sliding contact with the second wall surface 7B of the projection 7, and are curled and divided by receiving resistance from the wall surface 5B.

At this time, some of the chips W may extend as they are while being curled while being curled. In this case, the chips W are curled by receiving a resistance from the wall surface 5B constituting the guide portion, and FIG. As shown in FIG. 3, the tip extends so as to draw a large arc, and the tip thereof contacts the flank 3 of the cutting insert. Here, the recesses 11A and 11B for locking are formed in the flank 3 in advance, and the tip of the chip W is near the center of these locking recesses 11A and 11B or the boundary between the locking recesses 11A and 11B. Contact near the part.
When the tip of the chip W comes into contact with the vicinity of the central portion of the locking recesses 11A and 11B, the depth of the locking recesses 11A and 11B is guided while being guided along the inclined surface forming the locking recesses 11A and 11B. To the bottom of the door, where it is locked.

  On the other hand, when the tip of the chip W comes into contact with the vicinity of the boundary between the locking recesses 11A and 11B, the tip of the chip W is not immediately locked by the locking recesses 11A and 11B. While moving along the boundary as it is, it may move in a predetermined direction, for example, in the thickness direction as indicated by X in FIG. At this time, in this embodiment, the locking recesses 11A and 11B are arranged so as to cross obliquely at an angle of, for example, 45 degrees with respect to the thickness direction. Therefore, the locking recesses 11A and 11B are In this case, they are arranged so as to overlap each other in the thickness direction. For this reason, even when the tip of the chip W is not locked to the first locking recesses 11A and 11B, any one of the chips W is overlapped and overlapped in the moving direction as it goes downstream in the moving direction. The locking recesses 11A and 11B are locked.

  When the tip of the chip W is locked to the locking recesses 11A and 11B, the chip W whose tip is locked is restrained from further movement on the tip side. As a result, a strong bending force or shearing force acts on the spiral or arcuate chips W, and as a result, they are divided.

  On the other hand, in the case of finishing cutting with a small depth of cut, the chips W generated at the corner portion 4A of the cutting edge 4 scrape the inner rake face 2 of the corner portion 4A, so The protrusion of the wall surface 5B that faces the corner portion 4A of the projection portion 5 flows out between the one wall surface 7A and is guided as it is along the bisector L or in sliding contact with the first wall surface 7A. It is caused to collide with the curved surface and is curled by receiving resistance from the wall surface 5B. At this time, an edge portion may be formed along the ridge line on the convex curved surface of the wall surface 5B, and the chips W may be curled while being swung to the left or right by being applied to the edge portion.

  The curled chip W is thin and has a relatively low rigidity. Therefore, the curled chip W is not easily broken even when curled, and tends to extend in a spiral shape. Also in this case, the chip W extends while drawing a large arc while being curled, and the tip thereof contacts the flank 3 of the cutting insert. Then, similarly to the chip W in the case of the above-mentioned medium cutting, the tip of the chip W is locked by the locking recesses 11A and 11B formed in advance on the flank 3 and restrains further movement on the tip side. As a result, it receives a strong bending force or shearing force, and as a result, is divided.

  As described above, according to the cutting insert of this embodiment, the chip W can be divided in medium cutting with a relatively large cutting depth, and the tip of the chip W can be escaped even in finish cutting with a relatively small cutting depth. The movement can be restricted by restraining the surface, and the chips W can be suitably divided.

Moreover, according to the cutting insert of this embodiment, since the several recessed part 11 is formed in the flank 3, the surface area can be increased by that part, As a result, favorable heat dissipation is obtained.
In addition, when an operator grasps the cutting insert with a finger, it is usual to usually hold the flank 3 which is a side surface of the cutting insert. However, a plurality of recesses 11 are formed on the flank 3 in advance. Therefore, the recess 11 functions as a slip stopper. For this reason, when an operator grasps the cutting insert with a finger and fixes it to a holder, the workability | operativity improves.

As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, this invention is not limited to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.
For example, in the above-described embodiment, the present invention has been described with an example in which a plurality of regular quadrangular pyramid-shaped recessed recesses 11B are formed on a substantially flat portion of the flank 3 of a flat plate-shaped cutting insert. As shown in FIG. 5, the concave portion is not limited to the shape of a quadrangular pyramid-shaped concave portion 20 as shown in FIG. 5, but is also a hexagonal pyramid-shaped concave portion as viewed in plan view as shown in FIG. 6. Even if it is 30, as shown in FIG. 5 to 7, the fine shape of the upper surface of the cutting insert is omitted.
In addition, the recessed part and convex part which are formed in the flank 3 are flat as shown in FIGS. 5 to 7 to avoid the corner part to which a certain degree of strength is supplied to support the cutting edge 4 and to connect the corner parts. You may provide only in the part.

  In the above-described embodiment, the present invention has been described by taking a planar cutting insert having a rhombus in plan view as an example. However, the shape of the cutting insert to which the present invention is applied is not limited to a flat plate having a rhombus in plan view. Further, it may be a flat plate having a plan view polygonal shape such as a triangle, square, rectangle, or pentagon in plan view. Alternatively, it is not necessary to have an obtuse angle, and it may be rounded. Furthermore, the shape of the cutting insert to which the present invention is applied may be a flat plate shape that is circular or elliptical in plan view.

Moreover, in the said embodiment, although the several recessed part 11 was formed in the flank, it is not restricted to this, A convex part other than a recessed part may be sufficient, and also a recessed part and a convex part may mutually adjoin and make a pair. The concavo-convex portion to be formed may constitute one unit, and a plurality of concavo-convex portions forming these units may be formed.
The shape of these convex portions or concave-convex portions may be a rhomboid quadrangular pyramid shape in plan view, a regular hexagonal hexagonal pyramid shape in plan view, or a truncated pyramid shape. Also good.

  Moreover, in the said embodiment, although the cutting blade 4 and the scoop surface 2 are formed in each front and back of a flat insert main body, it is not restricted to this, The cutting blade 4 is only in any one of front and back. The present invention is also applicable to those having the rake face 2 formed.

  Furthermore, in the above-described embodiment, the plurality of recesses 11 are formed on the flank 3 in a state where they are obliquely intersected at an appropriate angle with respect to the thickness direction or circumferential direction of the cutting insert and are arranged vertically and horizontally. However, the present invention is not limited to this, and a plurality of concave portions or convex portions or concave and convex portions are formed in a state in which they are arranged vertically and horizontally along the thickness direction of the insert body 1 and the circumferential direction orthogonal to the thickness direction. May be.

1 Insert body, 2 rake face, 3 flank face, 4 cutting edge, 4A corner, 4B
Inclined part, 4C linear part, 5 protruding part, 5A top part, 5B wall surface, 7 convex part, 10 guide part, 11 concave part, 11A, 11B locking concave part, W chip.

Claims (5)

At least one of the front and back surfaces of the polygonal flat plate-shaped insert body is a rake face, the peripheral side surface of the insert body is a flank face, and the rim face of the rake face is the rake face and the flank face. In the cutting insert in which the cutting edge is formed at the intersecting ridge line part with
A guide portion is formed on the rake face to guide the tip of the chip to the flank while curling the chip.
A cutting insert characterized in that the flank is formed with concavities and convexities continuously and vertically and horizontally . The guide portion includes a protrusion formed on the rake face inside the cutting blade so as to protrude in the thickness direction of the insert body with a space between the guide blade and the rake face. A pair of the corners of the corners formed on both sides of the bisector of the corners so as to extend from the wall surface of the projections to the cutting edge side, the height being set lower than the height of the projections The cutting insert according to claim 1, wherein the cutting insert is formed of a convex portion . The unevenness formed on the flank is formed in a row in the longitudinal direction and in the lateral direction along the thickness direction of the insert main body and the circumferential direction orthogonal to the thickness direction. Cutting insert as described in. The concavo-convex shape formed on the flank is characterized by being formed continuously in length and width along a direction intersecting a thickness direction of the insert main body and a circumferential direction orthogonal to the thickness direction. The cutting insert according to claim 1 or 2. At least one of the front and back surfaces of the polygonal flat plate-shaped insert body is a rake face, the peripheral side surface of the insert body is a flank face, and the rim face of the rake face is the rake face and the flank face. In the cutting insert in which the cutting edge is formed at the intersecting ridge line part with
A guide portion is formed on the rake face to guide the tip of the chip to the flank while curling the chip.
The guide portion includes a protrusion formed on the rake face on the inner side of the cutting blade so as to protrude in the thickness direction of the insert body with a space between the guide blade and the rake face. A pair of convex portions that are formed to extend from the wall surface of the protruding portion to the cutting edge side on both sides of the corner portion with a bisector, and whose height is set lower than the protruding portion. Configured ,
On the flank, a plurality of concave portions having a pyramid shape or a truncated pyramid shape are continuously formed without forming a gap between each other, thereby forming concave and convex shapes continuously and vertically and horizontally. Cutting insert characterized by that.

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