JP5217449B2 - Cutting insert - Google Patents

Abstract

A cutting insert is provided to extend the life span of the cutting insert by securely removing swarf when the cutting insert is fed in a traverse direction to form a groove or a hole. A cutting insert comprises an insert body(1) having a shaft shape and a cutting blade section(2) formed at an end of the insert body. The cutting blade section has a rectangular flank surface(5). The flank surface is provided with a pair of transverse cutting blades(3) that extend lengthwise along the insert body, a front cutting blade(4) extending between the transverse cutting blades in a cross direction to the insert body, a pair of protrusions(11) extending toward a corner(6) at which the transverse cutting blade crosses the front cutting blade, and projections(12) spaced apart from the protrusions.

Description

  The present invention relates to a cutting insert used for grooving or parting off a work material in turning.

As a cutting insert used for this type of grooving or parting off, for example, Patent Document 1 discloses a pair of ridges extending in a substantially vertical direction on the top surface of a cutting head and a chip between these ridges. Breaker pit, a crease line extending between the front and rear pit parts of the chip breaker pit, and a pair of bars arranged in the front pit part between the crease line and the main cutting edge There has been proposed a device that has an action such as pushing a chip with a squeezing portion in the vicinity of the contact point between the crease line and the ridge.
JP-A-9-174308

  By the way, in the cutting insert of this patent document 1, while the said pair of bar | burr is arrange | positioned in the vicinity of the inner surface which both ridges face, both ridges extend in the said vertical direction, respectively, The tip portion is formed to extend away from each other toward a corner portion where the front main cutting edge, that is, the front cutting edge and the side cutting edge, that is, the side cutting edge intersect.

  However, in such a cutting insert described in Patent Document 1, the cutting insert is fed out in the longitudinal direction and grooving is performed in the work material by the front main cutting edge. When trying to perform processing that widens the groove width with the above-mentioned side cutting edge, the chips generated on the side cutting edge, particularly on the corner part side, are entirely on the tip that is continuous with the ridge. Will be collided. For this reason, in such a case, an increase in cutting resistance may occur, or chip clogging may occur and smooth chip disposal may not be achieved.

  Also in such grooving and parting-off of the work material, usually, a cutting fluid (coolant) is supplied to the cutting site where the cutting edge is cut into the work material so as to lubricate and cool it. Such cutting fluid is supplied from the rear end side of the insert toward the top surface of the cutting head, that is, the rake face so that supply to the cutting site is not hindered by the flowing out chips.

  However, in the cutting insert described in Patent Document 1, the tip of the ridge extending in the longitudinal direction as described above is formed so as to continuously extend toward the corner portion. The cutting fluid supplied to the tip side through between the ridge and the side cutting edge is only guided to the tip of the ridge and flows out to the side cutting edge side. Therefore, the cutting fluid cannot be sufficiently supplied to the front main cutting edge, particularly the corner side, and the cutting edge in the corner is easily damaged by heat or depending on the work material. The accuracy and quality of the groove wall surface and cut surface of the cut work material may be impaired.

  On the other hand, when the cutting insert is fed out in the vertical direction and only the grooving or parting of the work material is performed exclusively by the front main cutting edge, the chips generated by the front main cutting edge collide with the pair of bars. In this way, the chip breaker pit is fed while sliding, but if the chips continue to slide, the bar wears down and its height decreases, and eventually wears away. Therefore, the wear of the bar makes it impossible to control the chip, so that the cutting insert has a short life, and of course, the chip control becomes unstable even in the process where the bar wears down. It becomes difficult to perform proper processing.

  The present invention has been made under such a background, and in the cutting insert used for grooving or parting-off of the work material as described above, the cutting oil is reliably applied to the corner portion side of the front cutting edge. It can be supplied to prevent thermal damage and welding of the part, improve the accuracy and quality of the groove wall surface and cut surface of the work material, and send the insert laterally during groove processing Even when the groove width is widened, it is possible to achieve smooth chip disposal without causing an increase in cutting resistance. On the other hand, when the insert is fed out in the vertical direction exclusively and used for grooving or parting-off. It is an object of the present invention to provide a cutting insert capable of constantly controlling the insert and extending the insert life.

In order to solve the above-mentioned problems and achieve such an object, the present invention provides a pair of horizontal cutting edges extending in the longitudinal direction of the insert main body at the end of the shaft-shaped insert main body, A cutting edge portion having a quadrangular rake face provided with a front cutting edge extending in a direction intersecting the longitudinal direction is formed between the tips of the cutting edges, and the rake face includes the pair of lateral edges. A pair of ridges extending toward the corner where the cutting edge and the front cutting edge intersect are formed adjacent to the horizontal cutting edge connected to the corner, and the corner is orthogonal to the longitudinal direction. Te is formed in a convex arc shape in contact with the blade side cutting with the front cutting edge in a plan view as viewed from a direction facing the rake face Rutotomoni, the ridge, the tip end portion on the tip side in the plan view As you head, the crossing above the adjacent ridges Once it approaches the side, it is formed to form an arc shape that curves away from the side cutting blade as it goes further toward the tip, and the tip of the ridge is formed by the corner portion in plan view. It is formed in a straight line that is curved so as to be parallel to the convex arc formed, or extends in parallel with the direction of the chord of the arc, and the end of the protruding portion on the corner portion side and the corner portion In the meantime, a protruding portion protruding at an interval from the protruding portion is formed so as to extend from the tip end portion of the protruding portion toward the corner portion .

  Therefore, in such a cutting insert, first, with respect to a pair of ridges respectively extending toward a corner portion where the pair of side cutting blades and the front cutting blade intersect, the corner portions of these ridge portions are provided. Since the protruding portion that protrudes between the tip portion on the side and the corner portion is formed so as to be spaced apart, the tip passes between the pair of ridge portions and the horizontal cutting blade on the rake face. The cutting fluid supplied to the side flows into the corner portion side of the front cutting edge through a portion having a gap between the protrusion and the tip of the protrusion. For this reason, it becomes possible to sufficiently supply the cutting fluid to the corner portion side of the front cutting edge to achieve lubrication and cooling.

  In addition, since the protrusion is formed at a distance from the tip of the protrusion, it is generated on the side of the side cutting edge, particularly at the corner, when processing to widen the groove as described above. Since the chip to be cut does not collide with these protrusions and ridges at the interval, the entire chip is not subjected to resistance, and therefore the cutting resistance can be reduced also on the cutting insert side. it can. On the other hand, the chips that collide with the projecting portion thus spaced apart and the tip of the ridge portion flow out while being bent in the width direction, and are further curled in this outflow direction. It becomes easy to divide easily, and even if there is little resistance which a chip receives, it becomes possible to promote smooth and reliable chip disposal.

  On the other hand, when the insert body is fed in the longitudinal direction, that is, in the longitudinal direction to perform only grooving or parting of the work material, the chips generated by the front cutting blade are exclusively the tips of the pair of protrusions. By colliding with and slidingly contacting the part, it is strongly rounded in the width direction and processed easily to be divided, but these protrusions have a certain length so as to extend toward the corner part as described above. Since it extends on the rake face, even if it wears due to the sliding contact of the chips, it will not be worn away. Further, if the protrusion height at the tip of the protrusion is constant, the height does not change due to wear, and stable and smooth chip disposal can be achieved.

Furthermore, the protruding portions, since the formed so as to extend toward the corner portion from the tip of the protrusions, the processing such as widening the groove width feeding the insert in the lateral direction as described above In this case, chips generated on the corner portion side of the horizontal cutting edge can be guided to the rear end side of the cutting edge portion by this projection, and the chip contacts the bottom surface of the processed groove and scratches. It is possible to prevent such a situation.

  However, when the protrusion is formed so as to extend from the tip of the ridge toward the corner, the protrusion is not perpendicular to the longitudinal direction when viewed from the direction facing the rake face. It is desirable that the film is formed so as to extend in a direction intersecting with the axis extending in the longitudinal direction within a range of 15 ° to 75 °. That is, if the angle is smaller than the above range, the chips as described above may not be reliably guided to the rear end side of the cutting edge portion. It is difficult to guide the chips stably because the hitting of the chips close to the point, and there is a risk of causing early wear of the protrusions.

  In particular, when the protrusion is formed so as to extend from the tip of the protrusion toward the corner, the protrusion may be formed so as to extend continuously. A plurality of protrusions are formed at intervals between the tip of the ridge and the corner, and the plurality of protrusions are not directed from the tip of the ridge toward the corner. If it extends continuously, the cutting fluid can be supplied to the front cutting edge also from between these protrusions, and more efficient lubrication and cooling can be achieved.

  Thus, according to the cutting insert of the present invention, when performing grooving or parting-off of the work material, the cutting oil is reliably supplied also to the corner portion side of the front cutting edge for lubrication and cooling. It is possible to extend the life of the insert by preventing damage and welding of this part due to heat, and the accuracy and quality of the groove wall surface and cut surface of the work material are impaired by such heat damage and welding. Can be prevented. On the other hand, even when the insert is fed laterally during groove processing to widen the groove width, the entire chip can be prevented from colliding with the ridges, and the increase in cutting resistance is suppressed. On the other hand, it is possible to cut the chips reliably by the protrusions and the ridges to achieve smooth processing. Furthermore, even when the insert is fed out vertically for grooving or parting-off, the ridges where the chips come into sliding contact do not wear out, so the chips can be treated stably and smoothly over a long period of time. And a longer life cutting insert can be provided.

  1 to 8 show a first embodiment of a cutting insert according to the present invention. In the present embodiment, the insert body 1 is formed of a hard material such as cemented carbide and has a substantially square shaft shape (square column shape) extending along the axis L. The insert body 1 is perpendicular to the axis L and is in the longitudinal direction. (Axis L direction. Left and right direction in FIGS. 2 to 4) It is formed substantially symmetrically with respect to the plane M located in the center, and is perpendicular to the plane M in the width direction (in FIGS. 2 and 4). Up-down direction (left-right direction in FIG. 5) is located symmetrically with respect to a plane N including the axis L and extending in the thickness direction of the insert body 1 (up-down direction in FIGS. 3 and 5). .

  A cutting blade portion 2 is formed at the end portion (both ends) of the insert body 1 in the longitudinal direction. The cutting blade portion 2 includes a pair of horizontal cutting blades 3 extending in the longitudinal direction, and a lateral portion thereof. A substantially rectangular rake face 5 extending in the longitudinal direction and having a front cutting edge 4 extending in the width direction between the tips of the cutting blades 3 is formed so as to face the thickness direction. Has been. Note that the corner portion 6 where the front cutting edge 4 and the horizontal cutting edge 3 intersect each other has a cross section with the front cutting edge 4 and the horizontal cutting edge when viewed from a direction perpendicular to the longitudinal direction and facing the rake face 5. It is formed in a 1/4 convex arc shape that smoothly contacts the blade 3.

  Further, the upper surface portion 7 of the insert body 1 facing the same side as the rake face 5 in the thickness direction between the cutting edge portions 2 at both ends in the longitudinal direction is thicker than these cutting edge portions 2 as shown in FIG. It protrudes one step in the vertical direction. Furthermore, the upper surface portion 7 and the lower surface portion 8 of the insert body 1 opposite to the upper surface portion 7 are formed with mounting groove portions 7A and 8A having a V-shaped cross section over the entire length in the longitudinal direction. These mounting groove portions 7A and 8A come into contact with and sandwiched between a pair of jaw portions having a convex V-shaped cross section facing each other of the insert mounting seat formed on the holder of the insert detachable turning tool. The cutting insert is held by the holder and used for grooving or parting off of the work material. In addition, the end surface 7B facing the longitudinal direction of the upper surface portion 7 is an inclined surface that is inclined toward the lower surface portion 8 side as it goes toward the cutting blade portion 2 side.

  Furthermore, the front end surface facing the longitudinal direction and the both side surfaces facing the width direction of the cutting edge portion 2 are respectively the front cutting edge 4 and the flank 9 of the pair of side cutting edges 3, and the cutting insert of this embodiment These flank surfaces 9 are positive type inserts that are inclined so as to gradually recede from the rake face 5 including the intersecting ridge line part connected to the corner part 6 toward the lower surface part 8 side. Has been. Note that the end face and side face of the insert body 1 other than the flank face 9 of the cutting edge portion 2 have a planar shape extending in parallel to the thickness direction.

  The pair of side cutting blades 3 are formed so as to extend on a plane perpendicular to the thickness direction as shown in FIG. 3 including the corner portion 6, and from the corner portion 6 to the rear of the cutting edge portion 2. The taper is slightly inclined so as to approach each other in the width direction toward the end side. Further, the front cutting edge 4 is formed so as to extend in a straight line in the plan view, while in the thickness direction, both ends on the corner part 6 side are connected to the corner part 6 and the side cutting edge 3. It is formed so as to extend on the same plane, and the central portion in the width direction is formed in a concave curve shape so as to be slightly recessed in the thickness direction. At least the corner portion 6 is formed with a land 10 having a very small width as shown in FIG. 7, and the rake face 5 is separated from the side cutting edge 3, the front cutting edge 4, and the corner portion 6. The positive rake face is inclined so as to gradually recede in the thickness direction toward the inside.

  A pair of protrusions 11 extending toward the corner portion 6 are formed so as to protrude from the rake face 5 in the thickness direction further inside the rake face 5 which is a positive rake face. At the same time, a protrusion 12 that protrudes in the thickness direction is formed between the tip of the protrusion 11 on the corner 6 side and the corner 6 at a distance from the protrusion 11. Has been. In addition, the protruding portion 11 and the protruding portion 12 are formed so as to be spaced from the side cutting blade 3, the front cutting edge 4, and the corner portion 6.

  Of these, the protrusions 11 are connected to the inner wall surface 13 facing the inside of the rake face 5 facing each other in the plan view between the pair of protrusions 11 and the corner part 6 from which each protrusion 11 extends. It has an outer wall surface 14 that faces the side cutting blade 3 side, that is, faces opposite to each other, and in the present embodiment, it is a cross ridge line portion of the inner and outer wall surfaces 13 and 14 and is a ridge that protrudes most in the thickness direction. A protruding end surface 15 is formed in the portion. As shown in FIG. 8, the inner and outer wall surfaces 13 and 14 are inclined surfaces that are inclined so as to be separated from each other toward the rake face 2 side from the protruding end face 15, and intersect the protruding end face 15 with an obtuse angle. It has been made.

  Such a pair of protrusions 11 are branched into two from the rear end portion 11A narrower than the end surface 7B connected to the end surface 7B of the upper surface portion 7 toward the front end side of the cutting blade portion 2, respectively. It extends so as to be adjacent to the horizontal cutting edge 3 connected to each corner portion 6 toward each corner portion 6. Of these, the rear end portion 11B that branches off from the rear end portion 11A and reaches the position of approximately half the total length of the horizontal cutting blade 3 in the longitudinal direction is V-shaped toward the corner portion 6 in the plan view. The front end portion 11C extending from the rear end portion 11B has a convex curve shape that curves toward the adjacent horizontal cutting blade 3 in the same plan view. Is formed.

  More specifically, the front end portion 11C has a side cutting edge 3 adjacent to each protrusion 11 as the protruding end surface 15 moves from the rear end portion 11B toward the front end side of the cutting edge 2 in the plan view. It is formed so as to form an arcuate convex curve that is curved so as to be further away from the horizontal cutting edge 3 as it approaches the tip side once further. Accordingly, the inner wall surfaces 13 of the pair of ridge portions 11 in the distal end side portion 11C are formed in a concave curved surface shape that bends toward the side cutting blade 3 adjacent to each ridge portion 11 in the plan view. At the same time, the outer wall surface 14 is formed in a convex curved shape that is curved toward the side cutting blade 3 side, and the radius of curvature thereof is at the intersecting ridge line portion between the inner and outer wall surfaces 13 and 14 and the protruding end surface 15. The concave curve formed by the inner wall surface 13 is slightly smaller than the convex curve formed by the outer wall surface 14.

  The tip 11D of the ridge 11 is curved so as to be substantially parallel to the convex arc formed by the corner 6 in the plan view, or is formed in a straight line extending in parallel with the direction of the chord of the arc. The front end of the front cutting edge 4 forms a concave curve in the width direction and is substantially disposed at a position where it begins to be recessed in the thickness direction. However, the protruding end surface 15 of the tip portion 11D has a wide width so that a portion of the corner portion 6 located on the bisector of the corner portion 6 in the same plan view slightly protrudes toward the corner portion 6 side. In the portion extending from the protruding portion to the tip, the intersecting ridge line between the protruding end surface 15 and the outer wall surface 14 extends linearly so that the width of the protruding end surface 15 is gradually reduced. The outer wall surface 14 is formed to have a concave curved surface shape in a short range from the bent portion to the portion where the outer wall surface 14 has a convex curved surface shape in the distal end side portion 11C.

  Further, in the rear end side portion 11B of the ridge 11, the inner and outer wall surfaces 13 and 14 are formed so as to be bent in the plan view, and the inner wall surface 13 includes the rear end portion 11B. It is formed so as to bend in the bending direction at an obtuse angle with respect to the distal end side portion 11C. However, the bent portion 13A where the front and rear end side portions 11C and 11B forming the concave curved surface shape of the inner wall surface 13 intersect is formed in a convex curved surface shape that is smoothly connected to both concave curved surfaces, and the pair of protrusions 11 The interval in the width direction between the bent portions 13 </ b> A is made smaller than the interval in the width direction between the tips of the protruding end surfaces 15 of the pair of protruding portions 11 at the portion intersecting the protruding end surface 15. Further, the rear end portion 11B of the outer wall surface 14 is also smoothly connected to the tip end portion 11C having a convex curved surface shape in the same plan view, and is formed to be concave with respect to the horizontal cutting edge 3. Will be.

  Furthermore, the projecting end surface 15 of the projecting ridge portion 11 is perpendicular to the thickness direction from the rear end portion 11A to the rear end side portion 11B, and is slightly smaller than the groove bottom of the mounting groove portion 7A formed on the upper surface portion 7. The tip surface portion 11C has a flat surface disposed at a position retracted in the thickness direction, and is bent while being concavely bent from the position of the bent portion 13A toward the tip side as shown in FIG. After retreating one step in the vertical direction, a flat surface perpendicular to the thickness direction is formed again to reach the tip 11D of the ridge 11. In addition, the protruding end surface 15 at the distal end portion 11D is disposed so as to slightly protrude from a plane perpendicular to the thickness direction in which the side cutting edge 3 is formed. Further, the rake face 2 further inside than the inner wall surface 13 of the pair of ridge portions 11 is smoothly connected to the inner wall surface 13, and the width direction cross section or the longitudinal direction cross section along the thickness direction is also described. It is formed in a concave curved surface shape that forms a smoothly continuous concave curve.

  On the other hand, the protrusion 12 is positioned substantially on the bisector of each corner 6 and is disposed with a gap between the corner 6 and the protrusion 11. In this embodiment, the protrusion 12 also has a flat protruding end surface 16, a peripheral wall surface 17 that is arranged around the protruding end surface 16, intersects with the protruding end surface 16 at an obtuse angle, and inclines so as to gradually expand toward the rake face 5 side. As shown in FIG. 8, the height of the protruding end surface 16 in the thickness direction is equal to the height of the protruding end surface 15 of the protruding portion 11 at the tip end portion 11D. In addition, by forming such protrusions 12 at intervals from the protrusions 11, the peripheral wall surface 17 and the outer wall surface 14 intersect between the protrusions 12 and the protrusions 11. A concave portion 18 that is relatively recessed in the thickness direction is formed in the portion, and the bottom surface of the concave portion 18 has a concave curved surface shape as shown in FIG.

  Further, in the present embodiment, the protruding portion 12 is formed so as to extend from the tip portion 11D of the protruding portion 11 toward the corner portion 6, and more specifically, the protruding end surface 16 is an ellipse in the plan view. The long axis of the ellipse is inclined toward the outer side in the width direction and extends toward the corner portion 6 as it goes toward the distal end side of the cutting edge portion 2. Here, in the plan view, the direction in which the protrusion 12 extends toward the corner 6 intersects the axis L extending in the longitudinal direction of the insert body 1 at an angle θ in the range of 15 ° to 75 °. In this embodiment, the angle θ formed by the major axis of the ellipse and the axis L is 30 °, and is smaller than the angle formed by the bisector with respect to the axis L. Has been.

  The protrusion 12 is disposed such that the tip in the axis L direction, particularly the tip of the protruding end face 16 is located on the front cutting edge 4 side of the protruding portion 11. However, the protrusion 12 is formed to be sufficiently smaller than the protrusion 11, and for example, in the present embodiment, the protruding end surface 16, which has an oval shape, is formed in the corner portion 6 at the tip 11 </ b> D of the protrusion 11. It is made to be substantially the same size as the protruding end face 15 of the portion from the protruding side to the tip or slightly smaller than this. Also, reference numeral 19 in the figure denotes a display for identifying a pair of cutting blade portions 2 formed at both ends of the insert body 1, and in the present embodiment, this display 19 is the above-mentioned protrusion portion. 11 is a concave portion provided on the protruding end surface 15 of the rear end portion 11 </ b> A, and is formed only on one of the pair of cutting blade portions 2.

  In the cutting insert configured as described above, the insert body 1 is advanced in the direction of the axis L, and the work material is grooved or cut off by the front cutting edge 4 of the cutting edge portion 2 and the corner portions 6 at both ends thereof. In this case, the chips generated by the front cutting edge 4 and the corner portion 6 and flowing out in the direction of the axis L first collide with the protrusion 12 positioned at the forefront of the axis L and are guided inward in the width direction. Then, it is bent so as to receive resistance and be rounded in the width direction by colliding with and slidingly contacting the tip 11D of the ridge 11. The chips are also rounded in the width direction by the concave central portion in the width direction of the front cutting edge 4 being bent.

  Further, the chips thus rounded in the width direction are further rounded in the width direction while rubbing on the rake face 5 which is a concave curved surface inside the inner wall surface 13 of the pair of protrusions 11, and in the axis L direction, that is, It is also rounded in the outflow direction and sent out to the rear end side portion 11B of the ridge 11. And in this embodiment, the inner wall surface 13 in 11 C of front end side parts of these protrusions 11 is made into the concave curved surface shape curved toward the side cutting blade 3, and the inner wall surface of the rear end side part 11B Since the space | interval of the inner wall surfaces 13 of a pair of protrusion part 11 is made narrow by the bending part 13A with 13, the chip | tips collide with this bending part 13A, and the width direction rolled up as mentioned above And being separated by receiving a larger resistance in the outflow direction.

  However, when grooving or parting off the work material in this way, the cutting edge portion 2 is lubricated and cooled by the front cutting edge 4 or the corner portion 6 from the rear end side toward the rake face 5. When the cutting fluid is supplied, since the chips are scratched inside the pair of protrusions 11 as described above, the cutting fluid passes exclusively between the lateral cutting edges 3 outside these protrusions 11. In the cutting insert having the above-described configuration, the protrusion 12 formed between the tip 11D of the protrusion 11 and the corner 6 is connected to the protrusion 11. Since the protrusion 18 is protruded with a gap in between and the recess 18 that communicates from the rear end side to the front end side of the cutting blade portion 2 is defined between the protrusion portion 11 and the protrusion portion 12. It becomes possible to reliably supply the cutting fluid to the front cutting edge 4 through the recess 18.

  Therefore, according to the cutting insert, it becomes possible to effectively lubricate and cool the cutting site by the front cutting edge 4 with the cutting fluid supplied in this way, and it is possible to suppress an increase in cutting resistance and to occur during cutting. It is possible to prevent the front cutting edge 4 from being damaged or welded by the heat that is generated, and the insert life can be extended. Further, in particular, since the recess 18 between the protrusion 11 and the protrusion 12 is opened toward the corner 6 side portion of the front cutting edge 4, damage and welding at the portion are reliably prevented. It is possible to finish the groove wall surface in the grooving process of the work material formed by the corner part 6 side of the front cutting edge 4 and the cut surface in the cut-off process with high accuracy and high quality. Become.

  Further, when the insert body 1 is sent out in the longitudinal direction (axis L direction) and grooving or parting is performed in this way, the chips collide with the tip part 11D of the ridge part 11 and make sliding contact as described above. However, this resistance causes wear on the ridge 11, but the ridge 11 is formed to extend toward the corner 6 and has a certain length. Since it extends on the rake face 5, it will not wear out even if worn. That is, if it is like a bar described in Patent Document 1 that receives resistance by this chip, as the wear of this bar B progresses as shown in FIG. The height H gradually decreases, and eventually wear or burl B disappears. In FIG. 9A, the portions other than the bar B are denoted by the same reference numerals as those in the first embodiment shown in FIG.

  However, if it is the protrusion 11 that receives the resistance due to the chips as in the above-described cutting insert, the tip 11D is worn away even if the tip 11D is retracted due to wear as shown in FIG. 9B. It will never be lost. Moreover, in the present embodiment, the protruding end surface 15 at the distal end portion 11D of the protruding portion 11 is a flat surface perpendicular to the thickness direction, so that it is retracted due to wear as shown in FIG. 9B. However, the height does not change. Therefore, a constant resistance can be always given to the chips, and it is possible to provide a cutting insert with a long life while achieving smooth chip disposal.

  On the other hand, at the time of the grooving process, after the insert body 1 is sent out in the axis L direction to form a groove to a predetermined depth, the insert body 1 is sent as it is in the width direction (lateral direction) to widen the groove width. When processing is performed, cutting is performed by the side cutting blade 3 and the corner portion 6 on the side fed in the width direction. In this case as well, in the cutting insert configured as described above, the protrusion 11 and the protrusion Since the part 12 is spaced apart, smooth and reliable processing of chips can be achieved while reducing cutting resistance.

  That is, the chips generated by the horizontal cutting edge 3 and the corner portion 6 connected to the horizontal cutting edge 3 flow out from the corner portion 6 in the width direction of the insert body 1 with the width of the predetermined depth. 11 and collides with the outer wall surface 14 and the projecting portion 12, but since the projecting portion 11 and the projecting portion 12 are spaced at this time, the chip is entirely projected with these projecting portion 11 and the projecting portion 11. There is no so-called solid contact with the outer wall surface 14 of the portion 12, in particular, the ridge portion 11, and the resistance when chips collide can be suppressed. In particular, in the present embodiment, the outer wall surface 14 of the tip end portion 11C of the ridge portion 11 is formed in a convex curved shape that protrudes toward the horizontal cutting edge 3 in the above-described plan view, so that chips collide with the outer wall surface 14. Even in the portion to be cut, only the periphery of the portion that is convex and approaches the side of the horizontal cutting blade 3 collides, so that the cutting resistance received from the chips can be further reduced.

  On the other hand, the chips generated by the horizontal cutting blade 3 by colliding with the protruding portion 12 and the protruding portion 11 thus spaced from each other are a pair of protruding ridges cut by the front cutting blade 4. Similar to the case of colliding with the tip of the portion 11, it is bent so as to be rounded in the width direction (longitudinal direction in the insert main body 1) and pressed against the protruding portion 11 and the protruding portion 12 protruding on the rake face 5. As a result, it is curled so as to be rounded in the outflow direction (in the width direction in the insert body 1). Therefore, by bending in the width direction and the outflow direction in this way, the chips are easily divided by receiving stress, and the resistance when the chips collide with the protrusions 11 and the protrusions 12 is small as described above. However, it is possible to divide the chips reliably and to process them smoothly.

  Furthermore, since the protrusion 12 is formed between the tip 11D of the protrusion 11 extending toward the corner 6 and the corner 6, the insert body 1 is advanced in the direction of the axis L as described above. In addition to the case of performing grooving or parting off with the front cutting edge 4 or the case of performing processing that widens the groove width by feeding the insert body 1 in the width direction, for example, the width direction while the insert body 1 is advanced Even if the wall surface of the groove formed in the work material or the end face of the work material is cut obliquely by feeding it also in the width direction while retracting the insert body 1, It is possible to reliably guide and process between the tip 11D of the protrusion 11 and between the protrusion 11 and the protrusion 12.

  That is, when the insert body 1 is advanced and fed in the width direction to cut the groove wall surface and end face of the work material obliquely, the chips are disposed on the rear side with respect to the feed direction in the width direction, that is, the width feed direction. Although it produces | generates by the part extended to the width feed direction side of the front cutting edge 4 from the corner part 6, it flows out diagonally toward the width feed direction back side as it goes to the axis L direction rear side from the front cutting edge 4. When the protrusion 12 is disposed between the corner portion 6 on the rear side in the width feeding direction and the tip portion 11D of the protrusion 11, and the chips collide, the discharge direction of the chips follows the axis L. It is guided so as to be directed in the opposite direction, slidably contacts the ridge 11 on the rear side in the width feeding direction, or is wound inside the ridge 11 to be curled.

  On the other hand, when the insert body 1 is retracted and fed also in the width direction to cut the groove wall surface and end face obliquely, the tip of the horizontal cutting edge 3 extending rearward in the axis L direction from the corner portion 6 on the width feed direction side. Chips are generated by the side portion, and the outflow direction thereof is also a direction inclined obliquely toward the rear side in the width feeding direction as it goes toward the front end side in the axis L direction. However, since the protruding portion 12 is also formed between the corner portion 6 and the protruding portion 11 on the width feeding direction side on the outflow direction side with respect to the horizontal cutting edge 3 that generates chips, this protruding portion. The chip is guided so that the outflow direction thereof is along the width direction perpendicular to the axis L by colliding with the projection 12, and the chip 12 and the projection 12 are projected in the same manner as in the case where the insert body 1 is simply sent laterally and cut. It collides with the outer wall surface 14 of the strip 11 and is processed. That is, in the cutting insert having the above-described configuration, it is possible to reliably process the generated chips even when the insert body 1 is sent obliquely.

  In addition, the protrusion 12 in the present embodiment is formed such that the protruding end surface 16 has an oval shape in the plan view and extends from the tip 11D of the protrusion 11 toward the corner 6. As described above, when the insert body 1 is fed out only in the width direction to widen the groove width, chips that collide with the protrusion 12 are guided to the rear end side of the cutting edge 2 along the direction in which the protrusion 12 extends. Can be spilled out. For this reason, the chip generated by the horizontal cutting edge 3 and rounded in the outflow direction along the width direction of the insert main body 1 as described above is brought into contact with the cut groove wall surface to damage the groove wall surface. Can be prevented, and further high-precision and high-quality processing can be promoted.

  In the present embodiment, the extending direction of the projecting portion 12 extending toward the corner portion 6 in this way, that is, the major axis direction of the ellipse formed by the projecting end surface 16 of the projecting portion 12 in the plan view is the insert in the plan view. The axis L extends in the range of an angle θ of 15 ° to 75 ° with respect to the axis L extending in the longitudinal direction of the main body 1, but this is because the angle θ is too small and the protrusion 12 is formed on the insert main body 1. If it is close to the direction parallel to the longitudinal direction, that is, close to the direction in which the horizontal cutting blade 3 extends, the chips flowing out along the width direction of the insert body 1 are rounded and directly contact the groove wall surface. On the contrary, when the angle θ is too large and the extending direction of the protrusion 12 is close to the direction perpendicular to the horizontal cutting edge 3 in the plan view, the collision between the protrusion 12 and the chip is close to the point. It is difficult to get stable guidance This is because the protrusion 12 may be worn out at an early stage.

  However, in the present embodiment, the angle θ formed by the extending direction of the projection 12 with respect to the axis L in the plan view is smaller than the angle formed by the bisector of the corner 6 with respect to the axis L. However, if the angle θ is within the above range, the angle θ formed by the extending direction of the protrusion 21 with respect to the axis L is, for example, as in the second embodiment of the present invention shown in FIG. The angle between the bisector of the corner portion 6 and the axis L may be larger. Incidentally, in the second embodiment, the angle θ is set to 60 °. According to the second embodiment in which the angle θ is increased in this way, when the insert body 1 is fed in the direction of the axis L to perform grooving or parting-off processing, of course, the portion on the corner portion 6 side of the front cutting edge 4 is of course. Also, since it becomes possible to supply the cutting fluid to the corner 6 itself through the recess 18 in a wider range, it is possible to further reduce resistance and prevent thermal damage and welding.

  Further, in these first and second embodiments, the protrusion 12 is formed so as to continuously extend to the corner portion 6 side with the protruding end surface 16 having an oval shape in the plan view, but in FIG. As shown in the third embodiment of the present invention, a plurality of protrusions 22 such as a truncated cone are arranged at intervals from the tip 11D of the ridge 11 toward the corner 6 side. These protrusions 22 may extend discontinuously. In this case, in addition to the recess 18 formed between the protrusions 11, the cutting fluid can be supplied to the front cutting edge 4 side from the recess 18 formed in the space between the protrusions 22. It is possible to increase the oil supply amount.

FIG. 12 shows a reference example for the embodiment of the present invention. For example, it is used exclusively for grooving or parting off of a work material, and not for processing that widens the groove width. A cutting insert , which is a truncated cone-shaped projection 23 having no directivity, or a spherical projection is projected one by one between the tip portion 11D of the pair of protrusions 11 and each corner portion 6. I try to set it up . In this case, since the gap between the protrusion 23 and the tip 11D or the corner 6 can be increased, the amount of cutting fluid supplied to the front cutting edge 4 side is increased to achieve efficient lubrication and cooling. Can do. In the second and third embodiments shown in FIGS . 10 and 11 and the reference example shown in FIG. 12, the same reference numerals are used for the parts common to the first embodiment except the protrusions 21 to 23. The description is omitted.

On the other hand, in the first embodiment as well as in the second and third embodiments and the reference example , each of the protrusions 11 is adjacent to the distal end portion 11C of the pair of protrusions 11 in the plan view. The inner wall surface 13 is concavely curved toward the side of the horizontal cutting edge 3 and the outer wall surface 14 is convexly curved, and the insert body 1 is fed in the direction of the axis L to form a groove. Chips generated by the front cutting edge 4 when performing cutting or parting can be divided as described above by the mutually opposing inner wall surfaces 13 of the pair of protrusions 11 and the groove width is increased. Chips generated by the horizontal cutting edge 3 in the processing can be processed by the outer wall surface 14 and the protrusions 12 and 21 to 23.

  Further, since the outer wall surface 14 has a convex curved surface shape, even when the groove width is widened, the insert body 1 as described above is retracted while being fed in the width direction to form an inclined groove wall surface. When the chip flowing direction changes such that the chip flows out toward the tip side of the cutting edge portion 2 as it goes inward in the width direction of the insert body 1, the outer wall surface 14 is always opposed to the chip flowing direction. Therefore, it is possible to stably perform the treatment by causing the outer wall surface 14 to stably collide with the chips.

Further, in the first to third embodiments and the reference examples , the outer wall surface 14 of the leading end portion 11C of the ridge portion 11 is thus a convex curved surface in the plan view, whereas the rear end portion 11B. The outer wall surface 14 is formed in a concave curved surface shape that is curved with respect to the adjacent horizontal cutting edge 3, and therefore, a larger space is secured between the horizontal cutting edge 3 and the protrusion 11 at the rear end side portion 11 </ b> B. can do. And it is possible to supply more cutting fluid toward the concave portion 18 between the protrusions 12, 21 to 23 on the tip end side of the cutting blade portion 2 and the protruding portion 11 through the large gap portion. Therefore, according to these embodiments and reference examples, it is possible to more efficiently supply the cutting fluid to the front cutting edge 4, particularly to the corner portion 6 side, to achieve efficient lubrication and cooling.

In the first to third embodiments and the reference example , a portion where the projecting end surface 15 at the distal end portion 11D of the projecting portion 11 is located on the bisector of the corner portion 6 in the plan view is the corner portion. 6 is formed so as to protrude slightly toward the side 6 and become wide, but the protruding end surface 15 or the protruding portion 11 itself is at least in the range including the leading end portion 11D or the leading end portion 11D and the leading end side portion 11C. The width may be gradually narrowed toward the front end side, or may be formed to extend with a constant width.

Here, FIG. 13 to FIG. 16 respectively show the first to third in the case where the width of the protruding end surface 15 is gradually narrowed toward the tip end side in the range including the tip end portion 11C from the tip end portion 11D . Although the embodiment and the reference example are modified, the protruding portion 11 and the protruding portion 12 are not formed in the protruding end surface 15 or the protruding portion 11 by forming a widened portion at the distal end portion 11D. , 21 to 23 can be secured at a larger distance so that a large amount of cutting fluid can be supplied to the tip side, and the flow of the supplied cutting fluid can be smoothed to promote efficient supply.

  However, even when the width of the protruding end surface 15 at the distal end portion 11D of the protruding portion 11 is made narrower or constant as it goes toward the distal end side, the protruding portion 12 is made smaller than the protruding portion 11, that is, When the projecting end surfaces 16 of the projections 12 and 21 have an oval shape as in the modification shown in FIGS. 13 and 14, the width in the minor axis direction is the projecting end surface at the end portion 11 </ b> D of the projecting portion 11. The length in the major axis direction is made smaller than that of the projecting end face 15. 15 and 16, when the protrusions 22 and 23 have a truncated cone shape or a spherical shape and the protruding end face 16 is circular, the diameter of the circular protruding end face 16 is as follows. The width of the protruding end surface 15 of the protruding portion 11 at the tip end portion 11D is substantially equal to or smaller than this.

1 is a perspective view showing a first embodiment of the present invention. It is the top view which looked at the embodiment shown in FIG. 1 from the direction facing the rake face 5 perpendicular to the longitudinal direction. It is a side view of embodiment shown in FIG. It is a bottom view of embodiment shown in FIG. It is a front view of embodiment shown in FIG. It is an expansion perspective view of the cutting blade part 2 of embodiment shown in FIG. It is an enlarged plan view of the cutting edge part 2 in FIG. It is ZZ expanded sectional drawing in FIG. (A) The figure (in FIG. 7) which shows the change of the height H by progress of wear with the burl | bump of the invention described in patent document 1, and the ridge part 11 in (b) 1st Embodiment. It is a figure equivalent to a YY sectional view). It is the enlarged plan view of the cutting blade part 2 which looked at the 2nd Embodiment of this invention from the direction which opposes the rake face 5 perpendicular | vertical to the longitudinal direction. It is the enlarged plan view of the cutting blade part 2 which looked at the 3rd Embodiment of this invention from the direction which opposes the rake face 5 perpendicular | vertical to the longitudinal direction. It is an enlarged plan view of the cutting edge part 2 seen from the direction facing the rake face 5 perpendicular to the longitudinal direction of the reference example for the embodiment of the present invention. It is an enlarged plan view of the cutting edge part 2 seen from the direction which opposes the rake face 5 perpendicular | vertical to the longitudinal direction in the modification of 1st Embodiment. It is the enlarged plan view of the cutting blade part 2 seen from the direction which opposes the rake face 5 perpendicular to the longitudinal direction of the modification of 2nd Embodiment. It is the enlarged plan view of the cutting blade part 2 seen from the direction which opposes the rake face 5 perpendicular | vertical to the longitudinal direction in the modification of 3rd Embodiment. It is the enlarged plan view of the cutting blade part 2 seen from the direction which opposes the rake face 5 perpendicular to the longitudinal direction of the reference example .

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Insert body 2 Cutting edge part 3 Horizontal cutting edge 4 Front cutting edge 5 Rake face 6 Corner part 11 Projection part 11A Projection part 11 Rear end part 11B Projection part 11 Rear end side part 11C Projection part 11 Tip side portion 11D Tip portion 12, 21 to 23 of ridge portion 11 Projection portion 13 Inner wall surface of ridge portion 11 14 Outer wall surface of ridge portion 11 15 Projection end surface of ridge portion 11 16 Protrusion portions 12, 21 to 23 17 Projection end surface 17 Peripheral wall surface of projections 12, 21-23 18 Concave portion between ridge 11 and projections 12, 21-23 L Axis of insert body 1 Rake face perpendicular to longitudinal direction of insert body 1 5, an angle at which the direction in which the projecting portions 12, 21 to 23 intersect with the axis L extending in the longitudinal direction of the insert body 1 is viewed from the direction facing 5.

Claims (3)

A pair of horizontal cutting blades extending in the longitudinal direction of the insert main body at the end of the shaft-shaped insert main body, and a front cutting blade extending in a direction intersecting the longitudinal direction between the distal ends of the horizontal cutting blades A cutting blade portion having a rectangular rake face provided with a pair of protrusions extending toward a corner portion where the pair of side cutting blades and the front cutting edge intersect is formed on the rake face. The corner portion is formed so as to be adjacent to the horizontal cutting edge that is continuous with the corner portion, and the corner portion crosses the front cutting edge in a plan view as viewed from a direction orthogonal to the longitudinal direction and facing the rake face. Rutotomoni formed in a convex arc shape in contact with the blade, the protrusions, after the distal portion has approached once to the side cutting edge side adjacent each protrusions, toward the tip side in the plan view, Further away from the side cutting edge toward the tip side. The tip of the protrusion is curved so as to be parallel to the convex arc formed by the corner in the plan view, or the direction of the chord of the arc Are formed in a straight line extending in parallel with each other, and a protruding portion that protrudes with a gap from the protruding portion between the leading end portion of the protruding portion on the corner portion side and the corner portion , A cutting insert, characterized in that it is formed so as to extend from the tip of the ridge to the corner . The protrusion is formed so as to extend in a direction intersecting with the axis extending in the longitudinal direction within a range of 15 ° to 75 ° as viewed from the direction facing the rake face perpendicular to the longitudinal direction. The cutting insert according to claim 1 . A plurality of projections are formed between the tip of each ridge and the corner so as to extend from the tip of the ridge toward the corner. The cutting insert according to claim 1 , wherein the cutting insert is provided.

Images