JP2010023116A - Method for manufacturing cutting edge member of cutting tool and die for press forming of pressed powder body used in manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a pressed powder body for a vertical edge type throwaway chip with a chip breaker projected from the rake face, for example, by making punches advance or separate in the thickness direction of the chip body. <P>SOLUTION: A die for press forming of pressed powder is provided with punches 21 and 22 which mutually face and are relatively made to advance or separate and a die 24 defining a cavity 23 surrounding the periphery of the punches 21 and 22. The die is used to perform press forming of a pressed powder body by pressurizing material powder put into the cavity 23, with punches 21 and 22. A concave part 26 which recedes towards the outside of the cavity 23 is formed in the die 24 and material powder to be pressed by punches 21 and 22 is closely filled in the concave part 26, so that a projecting portion which becomes convex relatively to a portion adjoining to the direction side where punches 21 and 22 are separated is formed in a portion of the pressed powder body which is formed by the die 24. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a cutting blade member of a cutting tool such as a throw-away tip that is provided with a cutting blade and is detachably attached to the main body of the cutting tool, and compresses the raw material powder of such a cutting blade member. The present invention relates to a green compact press-molding die used in the manufacturing method in the case of manufacturing from a green compact.

  As a manufacturing method of the cutting blade member of such a cutting tool, for example, as a manufacturing method of the above throwaway tip in Patent Document 1, a rectangular flat plate-shaped chip body 1 as shown in FIG. Of the four peripheral surfaces arranged around the flat plate surface 2, a pair of peripheral surfaces positioned on the opposite sides is a rake surface 3, and the rake surface 3 intersects the flat plate surface 2 as a flank surface. A so-called vertical blade type throw-away tip manufacturing method in which the ridge line is the cutting edge 4 has been proposed. That is, in the manufacturing method described in Patent Document 1, the upper and lower punches that are opposed to each other in the direction perpendicular to the direction corresponding to the thickness direction of the chip body 1 (up and down direction in FIG. 19) (up and down movement) Using a press molding die provided with a die which is arranged so as to surround the upper and lower punches which are moved up and down and which surrounds the upper and lower punches to define a cavity between the upper and lower punches. The raw powder of the throw-away tip such as cemented carbide introduced in is compressed by upper and lower punches, and the green compact is press-molded.

  In the throw-away tip, the crossed ridge line between the other peripheral surface 5 adjacent to the rake face 3 of the peripheral surface of the tip body 1 and the rake face 3 is also used as the cutting edge 6. In this case, the other peripheral surface 5 is used as a flank of the cutting edge 6, and the cross ridge line portion between the other peripheral surface 5 and the flat plate surface 2 has a ¼ section. A convex curved surface such as a circular arc is formed, and at the corner portion of the rake face 3 where the intersecting ridgelines formed with the cutting edges 4 and 6 are intersected with each other, 1/4 is smoothly connected to the cutting edges 4 and 6. A convex arc-shaped corner portion 7 is formed. In addition, the throw-away tip described in Patent Document 1 is arranged in a direction in which the rake face 3 and the flat plate surface 2 and the other peripheral surface 5 serving as the flank face are orthogonal to each other via the cutting edges 4 and 6. Further, it is a throw-away tip with a breaker in which a chip breaker 8 is formed on the rake face 3. Further, in Patent Document 1, a pin is provided in the cavity so that the pin can be projected and retracted, and a through-hole serving as a mounting hole 9 into which a clamp screw or the like is inserted when the throw-away tip is attached to the tool body is provided. It is designed to form a green compact.

  On the other hand, in Patent Document 2, although it is a throw-away tip as the same cutting blade member, unlike the above-described vertical-blade type throw-away tip, a triangular flat plate surface facing the thickness direction of the triangular flat plate tip body is scooped. A method of manufacturing a so-called double positive type throw-away tip, in which a peripheral surface disposed around the flat plate surface is used as a flank, and an undercut portion recessed in the flank is formed. The green compact press mold is described. That is, in this Patent Document 2, using a press mold having a vertical punch that moves up and down in a direction corresponding to the thickness direction of the chip body, and a die that surrounds the periphery and defines a cavity, The die is divided into a plurality of pieces so as to be able to advance and retreat in a direction perpendicular to the direction corresponding to the thickness direction of the chip body, and a protrusion is provided on a surface portion forming a cavity of these divided dies, A portion corresponding to the undercut portion is formed on the peripheral surface of the green compact by the protrusion. The green compact molded by these press molds is sintered and manufactured to the above-mentioned throw-away tip.

Japanese Patent Laid-Open No. 10-146695 Japanese Patent Laid-Open No. 10-71497

By the way, the upper and lower punches that contact and separate the green compact formed on the vertical blade type throwaway tip as described in Patent Document 1 in the direction corresponding to the thickness direction of the chip body as in Patent Document 2. Then, try to mold using a press mold that includes a die that surrounds the die and defines a cavity . Then, an edge portion having a concave curved surface shape that matches the convex curved surface is formed on the peripheral edge portion of the sliding surface on the punch side that is in sliding contact with the sliding surface on the die side of these press surfaces. Since the edge portion of the edge portion becomes sharper as it goes toward the tip, breakage such as chipping is easily generated.

The present invention is made under such a background, using a press mold having an upper and lower punches that are opposed to each other and a die that is arranged around the upper and lower punches to define a cavity, For example, a cutting blade member of a cutting tool such as a vertical blade type throwaway tip is pressed against the punch body in a direction corresponding to the thickness direction of the tip body of the throwaway tip, and the pressure produced on the cutting blade member. Provided is a method for manufacturing a cutting tool member of a cutting tool capable of preventing damage as described above and extending the life of a press mold when manufacturing by molding powder, and manufacturing the same It is an object of the present invention to provide a green compact press mold suitable for use in the method.

In order to solve the above-described problems and achieve such an object, a manufacturing method of a cutting blade member of a cutting tool according to the present invention includes a punch that is relatively opposed to and separated from each other, and a punch that is close to each other. A cemented carbide or cermet raw material powder charged into the cavity is formed using a press molding die provided with a die that is disposed so as to surround the periphery and that defines a cavity with the punch. A method for producing a cutting tool member of a cutting tool, wherein the green compact produced on the cutting blade member provided with the cutting edge of the cutting tool is pressed by a punch, wherein the die is inserted into the cavity. thereby enabling disjunctive by dividing the drive means in a direction perpendicular to the disjunction direction or該離contact direction of the punch in between, a recess receding toward the outside of the cavity in the die, The wall of the recess facing the disjunction direction of serial punch, formed in a planar shape continuous to intersect at an obtuse angle to the pressing surface of the punch during compression and the bottom surface of the recess, compressed by the punch into the recess By filling the raw material powder, the portion of the green compact formed by the die has a chamfered plane and is relative to the portion adjacent to the side in which the punch is separated. A protruding portion that is convex is formed.

The green compact press-molding die of the present invention is a green compact press-molding die used in such a throw-away chip manufacturing method, and is opposed to and relatively separated from each other. A punch, and a die disposed so as to surround the adjacent punches and defining a cavity between the punches, wherein the die is separated from and attached to the punch with the cavity interposed therebetween. The die is divided into a direction or a direction perpendicular to the separation / contact direction and can be separated / attached by the driving means, and the die is formed with a recess that recedes toward the outside of the cavity . A wall surface of the concave portion facing the separation / contact direction is formed in a planar shape that is connected to the bottom surface of the concave portion and the press surface of the punch during compression so as to intersect an obtuse angle .

In the manufacturing method of the cutting blade member of such a cutting tool and the press molding die of the green compact used in the manufacturing method, the die of the press molding die that defines the cavity faces the outside of the cavity. By forming a recess that recedes, the raw material powder charged into the cavity is packed into the recess by being pushed out of the punch contact direction when compressed by the approach of the punch. Then, it is compressed and molded into the protruding portion. Accordingly, the cutting blade member has a chip body having a substantially flat plate shape, and includes a flat plate surface facing the thickness direction of the chip main body and a peripheral surface arranged around the flat plate surface. The above-mentioned vertical blade type in which a cutting edge is formed on at least one of an intersecting ridge line between the rake face formed on the flat plate surface and another peripheral surface adjacent to the rake face and the rake face. a throw-away tip, such green compact when molding by detaching the punch in the direction corresponding to the thickness direction of the chip body, for example, relief of the chip body protrusions in compact By forming the concave portion on the die side so as to be molded in a portion corresponding to the other peripheral surface corresponding to the surface, the crossing angle between the press surface of the punch and the sliding contact surface on the punch side should be secured at a right angle. To prevent such damage. It is possible to extend the scan molding die life. Further, by forming the wall surface of the concave portion into a planar shape that is continuous with the bottom surface of the concave portion and the press surface of the punch during compression so as to intersect at an obtuse angle, the cross ridge line portion of the chip body is a chamfered flat surface. Thus, a throw-away tip formed in a chamfer shape can be manufactured.

  Further, in the case where the cutting blade member is a flat throw-away tip and the punch is separated from the tip body in the direction corresponding to the thickness direction of the tip body, the manufacturing method described in Patent Document 1 Compared to forming a green compact by pressing and separating the punch in a direction perpendicular to the direction corresponding to the thickness direction as in the press molding die, the raw material powder can be compressed uniformly. Further, it is possible to prevent the tip body of the throwaway tip from being deformed and to improve the accuracy even when the vertical blade type throwaway tip is manufactured. In particular, in Patent Document 1, since the mounting hole 9 is formed so as to penetrate the chip body 1 in the thickness direction as shown in FIG. 19, the direction corresponding to the thickness direction, that is, the direction of attaching / detaching the punch A pin is provided in the cavity so that it can be projected and retracted in the direction perpendicular to the hole, and a through hole is formed in the green compact. When the raw material powder is compressed, the compression ratio changes slightly around this pin. As a result, there is a possibility that minute deformation may occur around the mounting hole 9 in the manufactured throw-away tip, but as described above, when the punch is moved away from and in the direction corresponding to the thickness direction of the tip body. In the cavity, a protrusion such as the pin protruding in the separating direction is provided between the punches that are close to each other while suppressing a change in the compression ratio of the raw material powder around the protrusion. Can be molded through holes in the powder, it is possible to prevent deformation around the mounting hole in the chip body.

  Here, in the case where a concave portion that recedes toward the outside of the cavity is formed on the die side of the press molding die in this way, the raw material powder that is packed in the concave portion and forms the protruding portion is compressed by the punch. As described above, the depth of the recess is compressed by being pushed into the recess so as to protrude from the separation / contact direction as described above. If the gap is too large with respect to the interval in the tangential direction, the raw material powder may not reach the back of the recess when the raw material powder is compressed, or the raw material powder may not be sufficiently compressed in the recess. Arise. For this reason, the depth of the concave portion is defined as the depth from the protruding end that protrudes toward the inside of the cavity and is continuous with both wall surfaces of the concave portion that faces the separation / contact direction of the punch. It is desirable that the distance be equal to or smaller than the distance in the separation direction, more desirably 50% or less, and even more desirably 25% or less of the distance.

Note that the projecting end of the concave portion that protrudes toward the inside of the cavity connected to both wall surfaces of the concave portion facing the separation direction is located on the die side that is in sliding contact with the punch that approaches the separation direction when the cavity is defined. When the concave portion is entirely retracted to the outside of the cavity with respect to the sliding contact surface, the die-side sliding contact surface and the wall surface of the concave portion itself become a portion itself, and the above-described distance between the two protruding ends is also the concave portion. It becomes the opening width to the die side sliding contact surface in the above-described separation / contact direction .

It is a cross-sectional view showing the first reference example in order to explain the press-molding die of the present invention. It is an expanded sectional view of the die side sliding contact surface 24C of the reference example shown in FIG. It is the top view seen in the punch separation / contact direction which shows the division example of the die | dye 24 of the reference example shown in FIG. FIG. 2 is a perspective view of a vertical blade type throw-away tip manufactured by a manufacturing method using the press-molding die of the reference example shown in FIG. 1. It is sectional drawing which shows the modification of the reference example shown in FIG. FIG. 6 is an enlarged cross-sectional view of a die side sliding contact surface 24C of the modification shown in FIG. 5. It is sectional drawing which shows the other modification of the reference example shown in FIG. FIG. 8 is an enlarged cross-sectional view of a die side sliding contact surface 24 </ b> C of the modified example shown in FIG. 7. The second reference example in describing the press forming die of the present invention is a cross-sectional view illustrating. FIG. 10 is a perspective view of a vertical blade type throw-away tip manufactured by a manufacturing method using the press mold of the second reference example shown in FIG. 9. It is a sectional view showing a third reference example in describing the press forming die of the present invention. It is a sectional view showing a fourth reference example in describing the press forming die of the present invention. FIG. 13 is an enlarged cross-sectional view of a die side sliding contact surface 24 </ b> C of the reference example shown in FIG. 12. FIG. 13 is a perspective view of a vertical blade type throw-away tip manufactured by a manufacturing method using the press-molding die of the fourth reference example shown in FIG. 12. A fifth reference example in describing the press forming die of the present invention is a cross-sectional view illustrating. It is a top view which shows a triangular flat plate type vertical blade type throwaway tip. It is a side view of the throw away tip shown in FIG. It is a sectional view showing a sixth reference example in describing the press forming die of the present invention. It is a perspective view showing a rectangular flat plate type vertical blade type throwaway tip.

FIGS. 1 to 3 show a first reference example for explaining the press molding die of the present invention. FIG. 4 shows a cutting blade member of a cutting tool using such a press molding die. The cutting blade member manufactured by one reference example of a manufacturing method is shown. Here, the cutting blade member is the above-described vertical blade type throw-away tip, that is, has a substantially rectangular flat plate-like tip body 11, and the thickness direction of the tip body 11 (from the left front side in FIG. 4). A pair of flat plate surfaces 12 having a square shape facing in the right back direction, and four peripheral surfaces arranged around the flat plate surface 12, and these peripheral surfaces are positioned on opposite sides of each other. A pair of peripheral surfaces (upper and lower peripheral surfaces in FIG. 4) serve as a rake face 13, a cross ridge line between the rake face 13 and the flat plate surface 12, and the rake face 13 and the remaining pair of other peripheral faces. Cutting edges 15 and 16 are formed on the intersecting ridge lines with the left and right peripheral surfaces in FIG. 4, respectively, and the flat plate surface 12 and the other peripheral surfaces 14 are flank surfaces for these cutting blades 15 and 16, respectively. ing.

  The rake face 13 protrudes in a direction perpendicular to the thickness direction of the chip body 11 so as to gradually rise from the peripheral cutting edges 15 and 16 toward the inside of the rake face 13. 17 is formed as a chip breaker for the cutting blades 15 and 16. Here, the projecting end of the projecting portion 17 is a rectangular flat surface 17A which is perpendicular to the flat plate surface 12 and the other peripheral surface 14 and is slightly smaller than the rake surface 13 along the thickness direction of the chip body 11. The flat surface 17A and the cutting blades 15 and 16 are formed in a concave curved surface in which a cross section perpendicular to the cutting blades 15 and 16 forms a concave arc or the like, and gradually as the distance from the cutting blades 15 and 16 increases. The breaker wall surface 17B is raised. Further, the chip body 11 is formed with a chip attachment hole 18 that opens in the center of the pair of flat plate surfaces 12 and penetrates the chip body 11 in the thickness direction.

As shown in FIG. 1, the press-molding die of the reference example for manufacturing such a throw-away tip as a cutting blade member has upper and lower surfaces opposed to each other by driving means (not shown) facing each other. Punches 21 and 22 and a die 24 that is disposed so as to surround the adjacent punches 21 and 22 and that defines a cavity 23 between the punches 21 and 22 are provided. Here, the upper and lower punches 21, 22 mutually separating direction (vertical direction in FIGS. Hereinafter referred to as punch disjunction direction.) Is to match the direction corresponding to the thickness direction of the chip body 11 The lower surface of the upper punch 21 and the upper surface of the lower punch 22 are press surfaces 21A and 22A for forming a flat plate surface of the green compact corresponding to the flat plate surface 12 of the chip body 11, respectively. The press surfaces 21A and 22A are flat surfaces perpendicular to the punch separation / contact direction.

Further, the die 24, (the left-right direction. The following 1 and 3, referred to as a horizontal direction.) A direction perpendicular to the punch disjunction direction as indicated by arrow line A in FIG. 1 and FIG. 3, The die 23 is divided into two dies 24A and 24B which are divided into two through the dividing surface P shown in FIG. 3 with the cavity 23 in between, and the dividing dies 24A and 24B are also not shown. Therefore, it is possible to make a relative separation in the horizontal direction. Then, the divided dies 24A and 24B come close to each other and come into close contact with each other to form the die 24, and the lower punch 22 slides the punch side sliding contact surface 22B on the die side sliding contact surface 24C of the die 24. Then, from above, the upper punch 21 descends while sliding the punch side sliding contact surface 21B against the die side sliding contact surface 24C, and is inserted into the die 24, as shown in FIG. As shown, a cavity 23 is defined (for the sake of illustration, a large gap is formed between the punch side sliding contact surfaces 21B and 22B and the die side sliding contact surface 24C. Actually, this gap is about several microns.) The punch side and die side sliding contact surfaces 21B, 22B, and 24C are all flat surfaces extending in parallel to the punch separation / contact direction.

Further, in the cavity 23 defined in this manner, a pin 25 protruding in the punch separation direction between the upper and lower punches 21, 22 that are close to each other, compresses the through hole that becomes the mounting hole 18 of the chip body 11. It is provided as a protrusion for molding on the body. That is, the pin 25 has a cylindrical shape, and is inserted into a circular hole 22C formed in the lower punch 22 so as to open at the center of the press surface 22A of the upper surface of the lower punch 22, and is also not shown. Thus, it is possible to move in and out of the cavity 23 from the press surface 22 </ b> A in the punch separation / contact direction independently of the lower punch 22. On the other hand, the upper punch 21 is formed with a circular hole 21C that opens at the center of the lower pressing surface 21A, and the tip (upper end) of the pin 25 protruding into the cavity 23 The punch 21 is received by being inserted into the circular hole 21 </ b> C.

The die 24 is formed with a recess 26 so as to open to the cavity 23 defined by the punches 21 and 22 and to recede to the outside of the cavity 23. A portion corresponding to the protrusion 17 formed on the rake face 13 of the eleven is formed by the recess 26. Here, the concave portion 26 is formed so as to recede with respect to the die side sliding contact surface 24C facing the horizontal direction of the divided dies 24A and 24B, and the inner surface thereof is perpendicular to the horizontal direction. A rectangular flat bottom surface 26A facing the inside of the cavity 23, and a concave portion while drawing a convex curved surface such as a convex circular arc in a horizontal direction from the four side ridges of the bottom surface 26A toward the inside of the cavity 23. 26 is formed of a wall surface 26B that gradually rises so as to widen the opening of the die 26 and continues to the die-side sliding contact surface 24C. The flat surface 17A of the protrusion 17 in the green compact and the bottom surface 26A and the wall surface 26B Portions corresponding to the breaker wall surface 17B are respectively formed.

Incidentally, these wall 26B, wall 26B continuous with the die-side sliding contact surface 24C facing the horizontal direction of the die 24 shown in FIGS. 1 and 2, so as to continue smoothly in contact with the die-side sliding contact surface 24C The positions of the press surfaces 21A and 22A of the upper and lower punches 21 and 22 when the cavity 23 is defined are the tangents between the wall surface 26B describing the convex curved surface and the die side sliding contact surface 24C. It is considered as a position. On the other hand, the die side sliding contact surface 24D that forms the peripheral surface corresponding to the other peripheral surface 14 of the chip body 11 in the green compact extends in parallel to the horizontal direction in addition to the punch separation direction. The wall surface 26B of the recess 26 that is a flat surface and continues to the die-side sliding contact surface 24D intersects the die-side sliding contact surface 24D at an angle while drawing the above-described projecting curved surface as shown by a broken line in FIG. The positions of the upper and lower punches 21 and 22 in the punch separation direction of the upper and lower punches 21 and 22 when the cavity 23 is defined are the intersection of the wall surface 26B and the die side sliding contact surface 24D. It is the position of both ends of the ridgeline.

  In order to mold the green compact produced in the vertical blade type throw-away tip by such a press molding die, the upper punch 21 is inserted into the cavity 23 before the upper punch 21 is inserted into the die 24. Raw material powder of a throw-away tip such as a cemented carbide mainly composed of WC or cermet mainly composed of TiC-TiN is introduced from the opening, and this raw material powder is used as the press surface 21A and the lower punch 22 of the upper punch 21. The inside of the cavity 23 is compressed by the press surface 22A. Accordingly, a green compact having a shape corresponding to the shape of the inner surface of the cavity 23 is formed, including the pin 25 protruding into the cavity 23.

  In the press-molding die having the above-described configuration, a recess 26 is formed on the die 24 defining the cavity 23 so as to recede from the cavity 23. In the method of manufacturing a cutting blade member using the above, the raw material powder charged into the cavity 23 is compressed in the above-described punch separation direction within the cavity 23 by the press surfaces 21A and 22A of the upper and lower punches 21 and 22. Then, it is packed so that it protrudes from the punching / separating direction and is also pushed into the concave portion 26 and receives pressure, and is formed into a green compact having a shape corresponding to the shape of the inner surface of the cavity 23 including the concave portion 26. The For this reason, on the peripheral surface of the green compact corresponding to the rake face 13 of the chip body 11, a protruding portion that protrudes to the peripheral surface is formed according to the shape of the inner surface of the recess 26. Thus, a throw-away tip having a flat tip body 11 is manufactured by compressing the raw material powder in a direction corresponding to the thickness direction of the tip body 11, that is, in the punching / separating direction, to form a green compact. Even in this case, it is possible to manufacture a throw-away tip including the protruding portion 17 such as the above-described chip breaker that protrudes from the peripheral surface of the chip body 11.

Further, like the manufacturing method and press mold described in Patent Document 1, the raw powder is compressed in a direction perpendicular to the direction corresponding to the thickness direction of the flat chip body, and the green compact is press molded. Then, since the dimension of the direction of the green compact are the compression becomes larger than the thickness of the green compact, it may become difficult to uniformly compress the raw material powder, in the above manufacturing method, described above In this way, the green compact is formed by the punches 21 and 22 coming into contact with each other in the direction corresponding to the thickness direction of the plate-like chip body 11, so that the raw material powder can be compressed relatively uniformly, deformation, etc. It is possible to manufacture a throw-away tip with little dimensional error. In particular, in the manufacturing method and press mold described in Patent Document 1, a pin is protruded into the cavity perpendicularly to the direction of contact of the upper and lower punches in order to form a chip mounting hole. Since the compression ratio slightly changes around the chip, even in the manufactured throw-away tip, a minute deformation occurs around the mounting hole. In the above reference example , as shown in FIG. Even when the mounting hole 18 is formed in the main body 11 in the thickness direction, the pin 25 for forming the through hole serving as the mounting hole 18 into the green compact is directed toward the punch separation direction. 23, it is possible to reliably prevent deformation of the compression ratio of the raw material powder around the pin 25 and deformation around the mounting hole 18 of the chip body 11. The ability.

In this way, in order to form the through hole serving as the mounting hole 18 of the chip body 11 in the green compact in this way, in the reference example described above , the cylindrical pin 25 is formed as a cavity from the press surface 22A of the lower punch 22 into the cavity. After the raw material powder is introduced into the cavity 23 with the pin 25 protruding, the upper and lower punches 21 and 22 are accommodated in the circular hole 21 </ b> C of the upper punch 21. By forming the green compact relatively close, the through hole is formed in the green compact by the pin 25. In this case, the through hole and the mounting hole 18 have a full length. As a result, it must be a cylindrical hole with a constant inner diameter. However, such a throw-away tip mounting hole 18 may be formed such that the opening at one end or both ends thereof is expanded so that the inner diameter increases toward the opening, such as a dish shape or a bell shape. .

  Therefore, in order to form a through-hole serving as the mounting hole 18 having such a shape into a green compact so that the opening on the surface side formed by the press surface 21A of the upper punch 21 is enlarged, Instead of forming the circular hole 21C in the punch 21, the upper punch 21 protrudes toward the lower punch 22 in the direction of punch separation in the press surface 21A, and its outer diameter faces the press surface 21A. After the core portion that expands so as to increase in diameter is formed as the protruding portion and the upper and lower punches 21 and 22 are relatively approached and the tip of the core portion comes into contact with the tip of the pin 25, this contact state The green compact may be formed while the pin 25 is retracted and pushed into the circular hole 22 </ b> C of the lower punch 22. Further, in order to form a green compact so that the opening on the surface side formed by the press surface 22A of the lower punch 22 has a larger diameter, the core whose outer diameter increases toward the press surface 22A side. The portion may be provided as the above-described protrusion so as to be able to protrude and retract from the press surface 22 </ b> A instead of the pin 25. In addition, when the core portion whose diameter is expanded toward the press surfaces 21A and 22A is used as the protrusion protruding into the cavity 23 in this way, the raw material powder is formed by the outer peripheral surface of the core portion during the green compact molding. Since it becomes easier to be pushed toward the outer peripheral side of the core part, that is, the concave part 26 outside the cavity 23, there is also an advantage that the material powder can be reliably and efficiently packed in the concave part 26.

Further, in the press forming die, divided dies 24A of the die 24 defining the cavity 23 is capable disjunction is divided into the horizontal direction, it is constituted by 24B, the die-side sliding as described above Even when the protruding portion that protrudes from the contact surface 24C is molded into a green compact, the molded green compact can be easily extracted from the press mold by dividing the die 24 into a plurality of parts. . In particular , the inner surface of the concave portion 26 forming the protruding portion gradually protrudes so as to expand the opening portion of the concave portion 26 from the bottom surface 26A toward the inside of the cavity 23 from the bottom surface 26A. In addition to the wall surface 26B, the die 24 is configured by being formed on both of the divided dies 24A and 24B which are divided so as to be able to be separated from each other in such a manner that the concave portions 26 face each other. Therefore, when separating the divided dies 24A and 24B after forming the green compact, a so-called draft angle is given to the wall surface 26B, so that the green compact can be surely used without damaging the formed protrusions. The effect that it can be extracted is also obtained.

However , in this way, the die 24 is divided and separated from the dividing surface P in the horizontal direction perpendicular to the bottom surface 26A of the recesses 26 facing each other. For example, as shown by the chain line in FIG. P is provided with a cavity 23 in between so as to intersect the bottom surface 26A perpendicularly along the punch separation direction, and as shown by an arrow B in FIG. The die 24 may be divided in a direction perpendicular to the direction (vertical direction in FIG. 3) so as to be separable. Further , when the wall surface 26B of the recess 26 is formed so as to be continuous with the die side sliding contact surface 24C without passing over the die side sliding contact surface 24C from the bottom surface 26A toward the inside of the cavity 23, for example, FIG. As shown by a chain line, a dividing surface P is provided perpendicular to the punch separation direction, and as shown by an arrow C in the figure, the die 24 is divided in the punch separation direction with the cavity 23 in between. The punches 21 and 22 may be separated from each other in the same direction.

Here, in the throw-away tip as described above, when the protruding portion 17 is provided on the rake face 13 to form a chip breaker, the breaker wall surface 17B is raked away from the cutting edges 15 and 16 as shown in FIG. In addition to being formed so as to rise gradually toward the inner side of the surface 13 and continue to the flat surface 17A of the protruding portion 17 at the end of the protrusion 17, the cutting blade 15, After retreating from 16, it may be a concave curved surface that gradually rises toward the flat surface 17. FIGS. 5 to 8 show modifications of the press-molding die of the first reference example when molding the green compact produced on such a throw-away tip. The same reference numerals are assigned to portions common to the first reference example , including the sixth reference example, and description thereof is omitted.

  Of these, first, in the modification shown in FIGS. 5 and 6, the convex portion 26 </ b> C protruding from the die side sliding contact surface 24 </ b> C to the inside of the cavity 23 at the periphery of the opening of the concave portion 26 in the die side sliding contact surface 24 </ b> C. Is formed adjacent to the concave portion 26, and the convex portion 26C has a cavity 23 so that the surface thereof protrudes at an angle from the die side sliding contact surface 24C as shown in FIG. A convex curved surface that protrudes inward and then retreats to the concave portion 26 side (outside of the cavity 23) with its convex curved section passing through the tip, and smoothly connected to the convex curved surface formed by the wall surface 26 </ b> B of the concave portion 26. Has been. Further, the positions of the press surfaces 21A and 22A of the upper and lower punches 21 and 22 when the cavity 23 is defined are on both outer sides of the concave portion 26 in the punch separation direction (the side in which the upper and lower punches 21 and 22 are separated from each other). Is a position where the convex portion 26C adjacent to the surface protrudes from the die-side sliding contact surface 24C, or a position slightly retracted further toward the above-mentioned direction of separation.

  On the other hand, in the modification shown in FIGS. 7 and 8, the punch-side and die-side sliding contact surfaces 21B, 22B, and 24C are different from the cavity 23 defined in the modification shown in FIGS. The position is shifted to the inside of the cavity 23 in the horizontal direction. That is, in this modified example, the recess 26 has an inner surface as shown in FIG. 8, and the opening of the recess 26 is expanded toward the inside of the cavity 23 while drawing a convex curved surface from the bottom surface 26A. Wall surface 26B that gradually rises, convex portion 26C that has a convexly curved surface continuously connected to this wall surface 26B and that protrudes toward the inside of cavity 23, and retracted from the protruding end of this convex portion 26C It is formed so as to include a wall surface 26D that intersects the position directly or via a narrow flat surface that is horizontal in the punch separation direction and extends in the horizontal direction and continues to the die side sliding contact surface 24C. Of these, the wall surface 26D is flush with the press surfaces 21A and 22A of the upper and lower punches 21 and 22 with the cavity 23 defined as shown in FIG.

  Therefore, according to the press-molding die of such a modification, it is formed by the convex portion 26C formed at the periphery of the opening of the concave portion 26 in FIGS. 5 and 6, and in the concave portion 26 in FIGS. Since the convex portion 26C is formed such that the portion corresponding to the breaker wall surface 17B of the green compact chip body 11 is recessed once with respect to the portions corresponding to the cutting edges 15 and 16, and is thus raised. Can be manufactured. Therefore, in such a throw-away tip, the rake angle of the cutting edges 15 and 16 can be set substantially larger on the positive angle side, and the sharpness can be improved.

  Further, in the modification shown in FIGS. 5 and 6, the convex portion 26 </ b> C is formed so that the positions of the press surfaces 21 </ b> A and 22 </ b> A at the time of defining the cavity 23 are directed in the direction in which the upper and lower punches 21 and 22 approach each other. By making the upper and lower punches 21 and 22 slightly recede in a direction away from each other than the position protruding from the contact surface 24C, and in the modification shown in FIGS. By interposing the flat surface between the wall surface 26D and the wall surface 26D, lands can be formed on the cutting blades 15 and 16 of the manufactured throw-away tip, and the strength of the cutting blade can be ensured.

In addition, the die 24 of the press molding die in which such a convex portion 26C is formed is divided in the horizontal direction indicated by an arrow A in FIGS. 5 and 7 as in FIGS. In other words, in the first reference example including these modified examples, by separating the die 24 in at least the direction in which the concave portion 26 recedes to the outside of the cavity 23 (the horizontal direction ), it is possible to make contact and disconnection. It is possible to form a green compact having an overcut portion that is relatively concave with respect to the protruding portion in a portion adjacent to the protruding portion in the direction in which the punches 21 and 22 are separated from each other. For example, in the modification shown in FIGS. 5 and 6, the bottom surface 26 </ b> A of the recess 26 is positioned inside the cavity 23 with respect to the die-side sliding contact surface 24 </ b> C, so that the protrusion 17 of the chip body 11 is The breaker wall surface 17B rises after being recessed once as it goes from the cutting edges 15 and 16 to the inside of the rake face 13, but the flat face 17A that becomes the protruding end of the protruding part 17 inside thereof is the cutting edge 1. , It is possible to manufacture such a position recessed from the inner side of the chip body 11 16.

By the way, as in the first reference example and the modification thereof, when the concave portion 26 that retreats toward the outside of the cavity 23 is formed in the die 24 and the protruding portion is formed in the green compact. The protruding portion is inserted into the cavity 23 as described above so that the raw material powder compressed in the punch separation direction by the press surfaces 21A and 22A of the upper and lower punches 21 and 22 is pushed into the recess 26. Since it is formed by being packed and compressed, if the depth D of the concave portion 26 is too deep, the compressive force toward the outside of the cavity 23 based on the compressive force in the punch separation / contact direction is reduced. The chip body 11 may be deformed at a portion of the green compact corresponding to the flat surface 17A of the protruding end of the protruding portion 17 and the like. For this reason, it is desirable that the depth D of the recesses 26 be equal to or less than an interval E in a range in which a compressive force acts on the raw material powder packed in the recesses 26 in the punch separation / contact direction.

Here, in the first reference example in which the recess 26 is entirely retracted from the die-side sliding contact surface 24C, the modified examples shown in FIGS. The compressive force on the outside of the cavity 23 based on the compressive force in the punch separation / contact direction acts on the powder in the punch separation / contact direction between the positions where the concave portion 26 starts to retreat from the die side sliding contact surface 24C. a during the interval E, i.e., between the first in reference example draws a convex curved surface as shown in FIG. 2 wall 26B and spacing E between the tangent position of the die-side sliding contact surface 24C, FIG. 7 And in the modification shown in FIG. 8, it is between the space | interval E between the positions of the crossing ridgeline of wall surface 26D of the recessed part 26, and die | dye slidable contact surface 24C. Accordingly, the depth D of the concave portion 26 in such a case is the depth from the tangent line or the intersecting ridge line to the bottom surface 26A, that is, the receding depth of the concave portion 26 from the die-side sliding contact surface 24C. It is desirable.

However, as in the modification shown in FIGS. 5 and 6, a convex portion 26 </ b> C that protrudes toward the inside of the cavity 23 is formed at the periphery of the opening portion of the concave portion 26 to the die-side sliding contact surface 24 </ b> C. The compressive force to the outside of the cavity 23 acting on the raw material powder pushed into the concave portion 26 is within the interval E between the protruding ends of these convex portions 26C adjacent to both sides of the concave portion 26 in the direction in which the upper and lower punches 21 and 22 are separated from each other. The depth D of the concave portion 26 into which the raw material powder is pressed and packed based on this compressive force is also the depth D from these protrusions. Become. Therefore, the depth D of the concave portion 26 includes both wall surfaces of the concave portion 26 facing the punch separation / contact direction, including the case where the concave portion 26 is entirely retracted from the die side sliding contact surface 24C as described above. 26B that protrudes toward the inside of the cavity 23 (the tangent line in the first reference example , the intersecting ridge line in the modification examples of FIGS. 7 and 8, and the protrusion 26C in the modification examples of FIGS. 5 and 6). It is desirable that the depth D from the protrusions is not more than the distance E between the protrusions in the punch separation direction. It should be noted that the depth D of the concave portion 26 is 50% or less of the interval E because the raw material powder is sufficiently packed in the concave portion 26 by the compressive force to the outside of the cavity 23 as the depth becomes shallower. Is more desirable, and it is even more desirable that the distance E is not more than 25% of the interval E.

Next, FIG. 9 shows a second reference example of the press molding die, 10 is produced by the process of cutting members of this second reference example cutting tool with a press molding die 2 shows a throw-away tip as a cutting blade member. The press-molding die of this reference example is characterized in that the inner surface of the recess 26 formed in the die 24 is formed by a smoothly continuous curved surface. That is, the inner surface of the recess 26 is formed in a concave curved surface in which the bottom surface 26A is concave with respect to the inside of the cavity 23 in the horizontal direction, and the wall surface continuous from the bottom surface 26A to the die side sliding contact surface 24C. 26B is a convex curved surface that smoothly contacts the concave curved bottom surface 26A. As shown in FIG. 9, also in the punch separation direction, the direction perpendicular to the punch separation direction and the horizontal direction ( Also in the direction orthogonal to the drawing of FIG. 9, the die 24 is formed so as to be in smooth contact with the die side sliding contact surface 24 </ b> C. Therefore, also in the second reference example , the depth D of the recess 26 is the depth from the die side sliding contact surface 24C to the bottom surface 26A, and the interval E is the wall side 26B in the die side sliding contact direction in the punch separation direction. The distance is between tangents that contact the surface 24C.

In the throw-away tip manufactured from the green compact molded by such a press mold, the tip has a convex curved surface on the rake face 13 of the tip body 11 as shown in FIG. A projecting portion 17 is formed in which the periphery forms a concave curved surface smoothly connected to the convex curved surface and is connected to the cutting blades 15 and 16. Thus, in the press mold of the present reference example , as described above, the inner surface of the recess 26 is formed by an uneven curved surface that smoothly continues to the die side sliding contact surface 24C. Based on the compressive force of the punches 21 and 22 in the punch separation / contact direction, the raw material powder can be densely packed in the concave portion 26, that is, the raw material also in the protruding portion formed on the peripheral surface of the green compact. It becomes possible to compress the powder uniformly, and it is possible to more reliably prevent the produced throwaway tip from being deformed. In this reference example , only the concave and convex curved surface that smoothly contacts the inner surface of the concave portion 26 is formed. For example, in the first reference example , the flat bottom surface 26A and the convex curved wall surface 26B are formed. In addition, the side ridge portion of the bottom surface 26A where they intersect may be formed so as to be in smooth contact with the concave curved surface so as to be continuous, and a plane that is in smooth contact with the curved surface may be interposed.

Then, 11, there is shown a third reference example of a press-molding die according to an embodiment of the present invention, the press-molding die, illustrated in Figure 19 described in Patent Document 1 When manufacturing such a throw-away tip, the crossed ridge line portion between the other peripheral surface 5 and the flat plate surface 2 as the flank face of the cutting edge 6 of the tip body 1 is included including the corner portion 7. It can be used to form a convex curved surface such as a convex circular arc in cross section. That is, in the first and second reference examples and modifications thereof, the breaker wall surface 17B having a concave curved surface is provided on the peripheral surface of the green compact corresponding to the rake face 13 of the tip body 11 of the throw-away tip. Although the case where the protrusion corresponding to the protrusion 17 such as a chip breaker is formed has been described , for example, in the green compact manufactured in the vertical blade type throw-away chip shown in FIG. It is possible to form a protruding portion on another peripheral surface 5 other than the surface, for example, corresponding to the flank, and it is relatively concave adjacent to the side of the protruding portion in which the punches 21 and 22 are separated. Thus, the retreating part can be shaped so as to retreat in a convex curved surface shape like the above-mentioned cross ridge line part.

Here, in the reference example shown in FIG. 11, the die side sliding contact surface 24D of the die 24 for forming the peripheral surface of the green compact corresponding to the other peripheral surface 5 of the chip body 1 shown in FIG. A recess 26 is formed which is retracted toward the outside of the cavity 23 and is also retracted from the die side sliding contact surface 24D. The inner surface of the recess 26 is punched in parallel to the die side sliding contact surface 24D. A bottom surface 26A that extends in the separation direction so as to retreat one step from the die side sliding contact surface 24D, and the bottom surface 26A at the both ends of the bottom surface 26A in the punch separation direction (upper and lower edges of the recess 26). A wall surface 26B having a concave curved surface such as a quarter-concave concave arc or the like that is connected so as to be in smooth contact with each other. The wall surface 26B is also smooth on the press surfaces 21A and 22A of the upper and lower punches 21 and 22 that come close to each other when the raw material powder is compressed to define the cavity 23 via the die side sliding contact surface 24D. They are in contact with each other.

Therefore, according to the third reference example , the other peripheral surface of the green compact corresponding to the other peripheral surface 5 of the chip body 1 is protruded from the flat plate surface 2 of the chip body 1. The convex curved surface adjacent to the side in the direction in which the punches 21 and 22 are separated, formed by the concave portion 26 together with the crossed ridge line portion and the corner portion of the green compact corresponding to the curved portion. It is possible to form a protrusion that is relatively convex with respect to the crossed ridge line portion. However, when such a convex curved cross-ridge portion of the green compact is to be formed by the press surfaces 21A and 22A of the upper and lower punches 21 and 22, for example, the die side sliding contact surface 24D of these press surfaces 21A and 22A. An edge portion having a concave curved surface shape corresponding to the convex curved surface is formed on the peripheral edge portion on the punch side sliding contact surface 21B, 22B side that is in sliding contact with the edge portion, and the edge portion intersects toward the tip. Since the corner becomes extremely sharp, breakage such as chipping is easily generated, whereas in this reference example , the concave portion 26 for forming the intersecting ridge line portion is formed on the die side sliding contact surface 24D, press surface 21A of the upper and lower punches 21, 22, 22A and a punch-side sliding contact surface 21B, since the cross angle between 22B can secure a right angle as well as other reference example, press-molding to prevent such damage It is possible to extend the lifetime of the mold.

In the die 24 in which the concave portion 26 for forming the other peripheral surface of the green compact is formed on the die side sliding contact surface 24D in this way, the peripheral surface of the green compact corresponding to the rake face 3 of the chip body 1 If the concave portions 26 of the first and second reference examples and the modified examples thereof are formed on the die side sliding contact surface 24C that will form the die, the intersecting ridgeline between the flat plate surface 2 and the other peripheral surface 5 It is possible to manufacture a throw-away tip in which the portion is formed in a convex curved shape and the corner portion 7 is formed in a convex curved shape, and the rake face 3 is formed with the protruding portion 17 acting as a chip breaker. And in the manufacturing method of the cutting blade member of the cutting tool of embodiment of this invention, and the press molding die of the green compact used for this manufacturing method, the wall surface of the recessed part 26 formed in this die side sliding contact surface 24D 26B, and the pressing surface 21A at the time of compression between the bottom surface 26A, by forming the planar contiguous so as to intersect at an obtuse angle to the 22A, the corner portion 7 the intersecting edge line region is the chamfered planes chamfer-like can be manufactured cutting insert is formed in a straight line.

On the other hand, in particular, the die side sliding contact of the die 24 for molding the other peripheral surface to the other peripheral surface of the green compact corresponding to the other peripheral surface as the flank of the tip body of the throw-away tip as described above. By forming a concave portion 26 that recedes toward the outside of the cavity 23 on the surface 24D, a protrusion that is relatively convex with respect to a portion adjacent to the direction in which the punches 21 and 22 are separated on the other peripheral surface. When molding the part , as described above, since the raw material powder is packed into the concave portion 26 based on the compressive force in the punch separating direction by the upper and lower punches 21 and 22, the protruding portion is molded. For example , as in the press-molding die of the fourth reference example shown in FIGS. 12 and 13, the maximum width W in the punch separating / attaching direction in the recess 26 is set to the opening of the recess 26 inside the cavity 23. Larger than the minimum width To be, it can be Takashimitsu raw material powder into the recess 26.

That is, in the fourth reference example , the recess 26 is formed so as to recede with respect to the die-side sliding contact surface 24D, and at least one of the wall surface 26B facing the punch separation / contact direction is formed in the recess. The punches 21 and 22 are formed so as to recede toward the outer side of the cavity 23 with respect to the opening portion of the die 26 on the slidable contact surface 24D. The raw material powder pressed into the recess 26 based on the compressive force in the punch separation / contact direction is also pressed and packed in the recess 26 in the direction in which the punches 21 and 22 are separated from each other. Therefore, it is possible to form a protrusion that is thicker than the thickness of the green compact at the opening of the recess 26 inside the cavity 23 on the peripheral surface of the green compact.

Here, in the present reference example , the concave portion 26 includes a flat bottom surface 26A extending along the punch separation direction retracted so as to be recessed by one step with respect to the die side sliding contact surface 24D, and the bottom surface 26A in the punch separation direction. It is comprised from the wall surface 26B extended from the peripheral part toward the inner side of the cavity 23 at the die side sliding contact surface 24D, and these wall surfaces 26B extend in the direction in which the punches 21 and 22 are separated from each other toward the inner side of the cavity 23. Then, the punches 21 and 22 are formed so as to extend in the approaching direction so as to intersect with the die side sliding contact surface 24D, so that the wall surface 26B is separated from the punches at the positions where the directions are changed. The maximum width W of the recess 26, which is the width in the contact direction, is the opening of the recess 26, which is the width in the punch separation direction at the intersection of the wall surface 26B and the die-side sliding contact surface 24D, to the inside of the cavity 23. It is made larger than the minimum width of the part. Therefore , the minimum width of the opening of the concave portion 26 to the inside of the cavity 23 is such that the width of the concave portion 26 is continuous with the wall surface 26B facing the punch separating direction of the concave portion 26 so It becomes equal to the interval E.

  More specifically, the wall surface 26B is formed in a concave curved surface shape such as a concave arc having a cross section of more than ¼ that is in smooth contact with the bottom surface 26A. It is made into the substantially ellipse shape extended in a punch separation / contact direction. Therefore, when the cross-section of the wall surface 26B is a concave arc shape exceeding 1/4, the maximum width W is the punch separation between the positions of the 1/4 arc from the bottom surface 26A of both wall surfaces 26B. The distance is in the tangential direction. The portion where the wall surface 26B intersects with the die side sliding contact surface 24D may be left in the shape of the concave curved surface, and the punch 21 is smoothly in contact with the concave curved surface toward the inside of the cavity 23. , 22 may be formed in a planar shape in a direction approaching each other.

Further, in this reference example , the press surfaces 21A and 22A of the upper and lower punches 21 and 22 have a convex shape such as a V-shaped cross section that is convex toward the direction in which the punches 21 and 22 approach each other. The press surfaces 21A and 22A intersect with the punch-side sliding contact surfaces 21B and 22B that are in sliding contact with the die-side sliding contact surface 24D. The angle is obtuse, and the wall surface 26B of the recess 26 forms a complementary angle of the intersection angle formed with the die-side sliding contact surface 24D, and the cavity 23 is defined by bringing the upper and lower punches 21 and 22 closer to each other. The press surfaces 21A and 22A and the wall surface 26B are arranged to be flush with each other. In order to extract the green compact from the press-molding die configured in this way, the die 24 is divided in the punch separation direction as shown by the arrow C in FIG. What is necessary is just to divide | segment and make contact possible in the horizontal direction (direction orthogonal to drawing of FIG. 12) parallel to the die | dye slidable contact surface 24D shown by the arrow A in FIG.

  FIG. 14 shows a throw-away tip manufactured from a green compact formed by a press-molding die configured as described above. The tip body 11 has a flat plate surface 12 with a cutting edge 15. The rake face 13 is formed in a butterfly shape in accordance with the cross-sectional shape of the cavity 23 and is formed so as to be recessed in a V shape toward the center. The intersecting ridge line portion has a convex curved surface shape, and the corner portion 19 of the cutting blades 15 and 16 has a convex curve shape such as an arc exceeding 1/4. The periphery of the chip attachment hole 18 on the flat plate surface 12 may be a flat surface perpendicular to the thickness direction of the chip body 11 in the direction connecting the rake surfaces 13, for example. In such a throw-away tip, when using the cutting edge 16 of the intersecting ridge line between the other peripheral surface 14 and the rake face 13 in which the protruding portion is formed in the green compact, the corner portion 19 is provided on the cutting edge 16. When the cutting blade 15 and the flat plate surface 12 intersecting with each other are given relief in a direction away from the cutting blade 16 along the rake face 13, for example, when grooving the work material by the cutting blade 16 Can be used as a throwaway tip.

However, if the maximum width W of the concave portion 26 in the punch separation / attachment direction is too large with respect to the minimum width of the opening to the inside of the cavity 23 (the interval E 2 ), the punch attachment / detachment by the punches 21 and 22 as described above. The raw material powder pushed into the concave portion 26 from the opening portion based on the compressive force in the direction is sufficient on the wall surface 26B side of the concave portion 26 that widens from the opening toward the outside of the cavity 23 (bottom surface 26A side). There is a risk that the corner 19 in the tip body 11 of the throw-away tip or the crossed ridge line portion between the flat plate surface 12 and the other peripheral surface 14 in the throwaway tip may be deformed. For this reason, it is desirable that the maximum width W of the concave portion 26 is within 110% of the minimum width of the opening inside the cavity 23.

FIG. 15 is a cross-sectional view showing a fifth reference example for explaining the press-molding die of the present invention. In this reference example , the upper and lower punches 21 and 22 are further inserted into chips in the green compact. Upper and lower inner punches 21D and 22D for forming a flat surface perpendicular to a direction corresponding to the thickness direction of the chip main body 11 at a portion corresponding to the center of the flat plate surface 12 of the main body 11, and the flat surface of the flat plate surface 12 The upper and lower outer punches 21E and 22E that are formed into valleys having a V-shaped cross section, like the green compact according to the fourth reference example , except for the flat surface portion, are formed at portions corresponding to both outer sides of the upper and lower outer punches. These upper and lower inner / outer punches 21D, 22D, 21E, and 22E can be separated from each other independently in a direction corresponding to the thickness direction. Accordingly, the press surfaces 21A and 22A of the upper and lower inner punches 21D and 22D are perpendicular to the punch separating direction, and the press surfaces 21A and 22A of the upper and lower outer punches 21E and 22E are outside the cavity 23, that is, on the concave portion 26 side of the die 24. The slopes are gradually inclined toward each other.

Accordingly, even in press-molding die of such fifth reference example, the as with the fourth reference example, of the maximum width W in the punch disjunction direction of the recess 26 into the cavity 23 inside the recess 26 Even if it is larger than the minimum width of the opening (the above-mentioned distance E), the raw material powder is surely packed in the concave portion 26 so as to be larger than the thickness of the green compact in the opening portion inside the cavity 23 of the concave portion 26. A thick protrusion can be formed on the peripheral surface of the green compact, and when a throw-away tip is manufactured from such a green compact, the cutting edge 15 and flat plate intersecting the cutting edge 16 via the corner 19 By providing relief to the surface 12, it can be used effectively for grooving of the work material. Furthermore, in this reference example , the punches 21 and 22 are divided into inner and outer punches 21D, 22D, 21E, and 22E so that they can be separated and connected independently. Therefore, when the raw material powder charged into the cavity 23 is compressed. First, the inner punches 21D and 22D are moved closer to push the raw material powder to the outside of the cavity 23, and then the outer punches 21E and 22E are moved closer to push the raw material powder pushed to the outer side further to the outer side of the cavity 23. Thus, the raw material powder can be more densely and efficiently packed in the recess 26.

By the way, in the first to fourth reference examples , the case of manufacturing the rectangular flat plate type vertical blade type throwaway tip as shown in FIG. 4, FIG. 10, FIG. 14 and FIG. For example , the fifth reference example can also be applied to manufacture a throw-away tip having a substantially triangular flat-plate-shaped tip body 11 as shown in FIGS. . This throw-away tip is also used for grooving of a work material and the like. Of the triangular plate surfaces 12 facing the thickness direction of the chip body 11, one flat plate surface 12 (see FIG. In FIG. 17, the upper flat surface 12) is a flat surface perpendicular to the thickness direction, and the other flat surface 12 (the lower flat surface 12 in FIG. 17) is substantially flat. At the corners of the triangle formed by these flat plate surfaces 12, one of a pair of peripheral surfaces adjacent to each other at the corners is a rake surface 13 and the other peripheral surface 14 is a flank surface. A cutting edge 16 is defined as a crossing ridge line between the outer peripheral surface 14 and the other peripheral surface 14.

  And the corner part 19 which makes a convex circular arc shape is formed in the both ends of this cutting blade 16, and the intersection ridgeline part of the said other peripheral surface 14 and the said corner | angular part of the flat plate surface 12 which continue to these corner parts 19 The chip body 11 faces outward in the thickness direction so that a cross section perpendicular to the extending direction of the intersecting ridge line forms a convex curve such as a convex arc continuously connecting the flat plate surface 12 and the other peripheral surface 14. Thus, it is formed in a convex curved shape that recedes so as to be relatively concave with respect to the peripheral surface 14. Further, among the corner portions of the flat plate surface 12 intersecting with these intersecting ridge line portions, the portion on the one flat plate surface 12 side is from the intersecting ridge line portion side to the flat surface side of the central portion of the flat plate surface 12. It is set as the inclined surface which inclines toward the said other flat plate surface 12 of an other side as it goes. Therefore, if such a triangular flat plate throwaway tip is manufactured from a green compact by powder press molding, the green compact also becomes a triangular flat plate shape. In the method and mold for forming the green compact by compressing perpendicularly to the direction corresponding to the thickness direction of the main body 11, it is more difficult to uniformly compress the raw material powder, and it is practically manufactured. I can't.

Thus, FIG. 18, (cross-sectional view corresponding to ZZ cross-section of the cutting insert shown in FIG. 16) Sixth sectional view showing a reference example of the press molding die in the case of producing such a throw-away tip , and the like the reference example of the fifth, respectively upper and lower inner punches 21D are upper and lower punches 21, 22, 22D and the upper and lower outer punches 21E, is composed of a 22E, the upper and lower inner and outer punches 21D, 22D, 21E, 22E Are relatively separable independently of each other. However, on the upper punch 21 side, the press surface 21A of the upper inner punch 21D is in the punch separation direction so as to form a portion of the green compact corresponding to the flat surface at the center of the one flat plate surface 12. In contrast, the upper and outer punches 21E have three upper and outer punches 21E arranged around the upper and inner punches 21D in accordance with the corner portions of the green compact formed into a triangular flat plate shape. Thus, the press surface 21A is made to be an inclined surface in which the distance from the press surface 22A of the lower punch 22 gradually increases toward the concave portion 26 side of the die 24. Yes.

On the other hand, on the lower punch 22 side, the lower inner punch 22D and the three lower outer punches 22E are disposed at positions facing the upper inner punch 21D and the three upper and outer punches 21E of the upper punch 21, respectively. Of these, the three lower and outer punches 22E can be separated from and connected to the upper and outer punches 21E in the same manner as the upper and outer punches 21E. However, the press surfaces 22A of these lower inner and outer punches 22D and 22E are both flat surfaces perpendicular to the punch separation direction in accordance with the flat surface of the other flat plate surface 12 of the chip body 11 being flat. The cavities 23 are flush with each other in a defined state. Therefore, in the present reference example , only the press surface 21A of the upper and outer punches 21E moves toward the concave portion 26 with respect to the plane perpendicular to the punch separating direction, and the press surface 22A of the lower outer punch 22E that faces the lower punch 22 is opposed. It is set as the inclined surface inclined so that it may space apart from. Further, the die 24 is divided into three parts at positions corresponding to the respective corner portions of the triangular flat plate-shaped green compact, and can be detached and attached in a direction perpendicular to the punch separating and attaching direction.

Therefore, according to the press-molding die of the sixth reference example as described above, even the throw-away tip having the triangular flat plate-like tip body 11 as described above can be easily obtained from the green compact obtained by uniformly compressing the raw material powder. It can be manufactured. And on that, the intersection ridgeline part of the above-mentioned other peripheral surface 14 of chip body 11 and the corner of flat plate surface 12 has receded from peripheral surface 14 in the shape of a convex curved surface as described above, Accordingly, in the green compact manufactured on the throw-away tip, the portion corresponding to the peripheral surface 14 is relative to the portion corresponding to the intersecting ridge line portion adjacent to the side in which the punches 21 and 22 are separated from each other. Even if it becomes a projecting portion that becomes convex, a recess 26 that recedes toward the outside of the cavity 23 is formed in the die 24, so that the projecting portion is made dense by filling the recess 26 with the raw material powder. It can be reliably generated on the 24 side.

Further, even in this reference example , even if the maximum width W in the punch 26 in the recess 26 is larger than the minimum width of the opening to the inside of the cavity 23 of the recess 26 (the interval E), the recess 26 It is possible to make the raw material powder densely packed and to form the projecting portion thicker than the thickness of the green compact at the opening inside the cavity 23 of the concave portion 26. In the away insert, a relief is given to the corner portion of the flat plate surface 12 connected to the other peripheral surface 14 which is a flank of the cutting edge 16 via the intersecting ridge line portion, and the throw away insert is removed from the work piece. It is possible to use it effectively for grooving. In addition, even if the intersecting ridge line portion between the flat plate surface 12 and the other peripheral surface 14 is a convex curved surface as described above, the press surfaces 21A, 22A of the upper and lower outer punches 21E, 22E and the punch side sliding contact surface The strength of the intersecting ridge line portion with 21B, 22B can be secured, and the press surface 21A of the upper and outer punches 21E is a press surface of the lower outer punch 22E that is a flat surface perpendicular to the opposing punch separation direction. Since the inclined surface is gradually separated from 22A toward the concave portion 26, it is possible to more reliably and efficiently promote the filling of the raw material powder into the concave portion 26.

Incidentally, these first to fourth reference examples and the modifications thereof, and beauty in an embodiment of the present invention based on these, it has been described as applied to the production of throw-away tip of the vertical blade type, except the indexable insert It can also be applied when manufacturing cutting blade members of other cutting tools from green compacts of the raw material powder, and is also applicable when manufacturing throwaway inserts or chips having a chip body other than a flat plate shape. Is possible. Further, even in a throw-away tip having a flat tip body, a flat surface facing the thickness direction is a rake face, and at least one of peripheral surfaces arranged around the flat face is a flank face. It is also possible to apply this method when manufacturing a throw-away tip having a cutting edge formed between the rake face and the peripheral surface to be the flank face. not obtained there usually the protrusion as described above in addition to the peripheral surface is formed to be, also above problems, considering the action and effect, in particular for producing indexable insert of the vertical blade type It can be said that it is more effective when applied to.

1,11 Chip body 2,12 Flat surface 3,13 Rake face 4,6,15,16 Cutting edge 5,14 Other peripheral surface of chip body 1,11 7,19 Corner part 9,18 Mounting hole 17 Projection part 21, 22 Punch 21A, 22A Press surface 21B, 22B Punch side sliding contact surface 23 Cavity 24 Die 24C, 24D Die side sliding contact surface 25 Pin (projection)
26 concave portion 26A bottom surface of concave portion 26B wall surface 26C of concave portion 26 convex portion D depth from a protruding end that protrudes toward cavity 23 side along both wall surfaces 26B facing the direction of punch separation of concave portion 26 E punch separation of concave portion 26 The distance in the punch separation direction between the protrusions that are continuous with both wall surfaces 26B facing the contact direction and protrude toward the cavity 23 (the minimum width of the opening of the recess 26 inside the cavity 23)
W The maximum width of the recess 26 in the punch separation / contact direction

Claims (9)

  A press-molding die comprising punches that are opposed to each other and relatively separated from each other, and a die that is disposed so as to surround the adjacent punches and that defines a cavity between the punches. A method for producing a cutting tool member of a cutting tool, wherein the raw powder charged into the cavity is compressed by the punch, thereby pressing the green compact produced on the cutting tool member of the cutting tool, A portion formed by the die in the green compact is formed by forming a recess in the die that recedes toward the outside of the cavity, and filling the recess with the raw material powder that is compressed by the punch. A method of manufacturing a cutting blade member for a cutting tool, comprising: forming a protruding portion that is relatively convex with respect to a portion adjacent to the side in which the punch is separated.   The cutting blade member has a chip body having a substantially flat plate shape, and includes a flat plate surface facing the thickness direction of the chip main body and a peripheral surface disposed around the flat plate surface, and formed on the peripheral surface A throwaway tip having a cutting edge formed on at least one of the intersecting ridgeline between the rake face and the flat plate surface, and the other ridge face adjacent to the rake face and the rake face, The punch is separated in a direction corresponding to the thickness direction, and the protrusion is formed in a portion corresponding to the peripheral surface of the chip body in the green compact by the concave portion formed in the die. The manufacturing method of the cutting-blade member of the cutting tool of Claim 1 characterized by these.   A press molding die of a green compact used in the method for manufacturing a cutting blade member of a cutting tool according to claim 1 or 2, wherein the press mold is close to a punch that is opposed to and separated from each other. A die which is disposed so as to surround the peripheries of the punches and defines a cavity between the punches, and the die has a recess which recedes toward the outside of the cavity. A green compact press mold.   The recess is connected to both wall surfaces of the recess facing the punching direction of the punch, and the depth from the protruding end protruding toward the inside of the cavity is the distance between the protruding directions between the protruding ends. The green compact press-molding die according to claim 3, characterized in that:   5. The green compact press-molding die according to claim 3, wherein the concave portion is formed by a curved surface having a smoothly continuous inner surface.   6. The concave portion according to any one of claims 3 to 5, wherein the concave portion has a maximum width in a direction of separation of the punch that is larger than a minimum width of an opening portion inside the cavity. Press molding mold for green compact.   The green compact press-molding die according to claim 6, wherein the maximum width is 110% or less of the minimum width.   8. The die according to claim 3, wherein the die is divided in a direction in which the punch is detached or perpendicular to the direction of the separation with the cavity interposed therebetween. A green compact press mold according to any one of the above.   The green compact according to any one of claims 3 to 8, wherein a protrusion is provided between the punches that are close to each other in the cavity so as to protrude in a direction of separating the punch. Press mold.

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