JP2011098392A - Method for manufacturing cutting edge member of cutting tool, and press-forming die for green compact used in the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a cutting edge member of cutting tool capable of preventing a step part formed in the scooping surface of the cutting edge member from extending up to the cutting edge, and provide a press-forming die for a green compact used in the method. <P>SOLUTION: The green compact is press-formed to manufacture a cutting edge member of cutting tool by pressing powder material charged into a cavity A by using a plurality of punches 21 and 22 of a press-forming die 20 equipped with the plurality of punches 21 and 22, and equipped with a die 23 for defining the cavity A. The plurality of punches 21 and 22 are composed of a plurality of dividing punches 25, 26, 31 and 32 which are divided with the dividing surfaces extended in the separating and approaching direction of the punches, and a portion corresponding to the cutting edge part of the cutting member is formed by a unit of dividing punch 25 and 31. <P>COPYRIGHT: (C)2011,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.

Conventionally, as a manufacturing method of a cutting blade member of a cutting tool, for example, as a manufacturing method of the above throwaway tip in Patent Document 1, a flat plate chip body 1 having a rectangular flat plate shape as shown in FIG. 25 is formed. Of the four peripheral surfaces arranged around the surface 2, a pair of peripheral surfaces located on opposite sides is a rake surface 3, and the ridge line between the rake surface 3 and the flat plate surface 2 serving as a flank surface A so-called vertical blade type throw-away tip manufacturing method has been proposed in which a cutting blade 4 is used. That is, in the manufacturing method described in Patent Document 1, as shown in FIG. 26, a direction corresponding to the thickness direction (vertical direction in FIG. 25) of the chip body 1 (the direction from the left front side to the right back side in FIG. 26). ) So as to surround the upper and lower punches 151 and 152 that are opposed to each other in the vertical direction (vertical direction in FIG. 26) and that move upward and downward. Using a press mold 150 provided with a die 153 that is disposed and defines a cavity A between the upper and lower punches 151 and 152, a throw of cemented carbide or the like thrown into the cavity A The raw powder of the away chip is compressed by the upper and lower punches 151 and 152 to press the green compact.
In this press molding die 150, an upper punch 151 is composed of a first divided punch 154 and two second divided punches 155 arranged on both sides of the first divided punch 154, and a lower punch 152 is a third punch. The divided punch 156 includes two fourth divided punches 157 arranged on both sides of the third divided punch 156.
In the press mold 150 configured as described above, lower end surfaces of the first divided punch 154 and the second divided punch 155 are press surfaces 154A and 155A for compressing the raw material powder, and the press surfaces 154A and 155A are chips. Of the pair of rake faces 3 of the main body 1, one rake face 3 and a portion corresponding to the cutting edge 4 are formed, and the press faces 156A and 157A of the third divided punch 156 and the fourth divided punch 157 are the other. Parts corresponding to the rake face 3 and the cutting edge 4 are formed.
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 serves 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 convex 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 this Patent Document 1, a pin 158 is provided in the cavity A so as to be able to protrude and retract, and becomes a mounting hole 9 into which a clamp screw or the like is inserted when the throwaway tip is attached to the tool body. Through holes are formed in the green compact.
In the conventional press molding die 150, the upper end surface of the third divided punch 156 is arranged above the upper end surface of the fourth divided punch 157 in the filling step of filling the raw material powder into the cavity A. In this state, when the raw material powder is filled into the cavity A and the raw material powder is filled into the cavity A, the upper punch 151 presses the upper surface of the raw material powder.
When the upper punch 151 presses the upper surface of the raw material powder, the first divided punch 154 protrudes downward to press the raw material powder, and the third divided punch 156 pulls downward to suck the raw material powder directly under the pin. The filling ratio of the raw material powder is adjusted.

Japanese Patent Laid-Open No. 10-146695

However, in the manufacturing method of the cutting blade member of the conventional cutting tool and the press mold of the green compact, a slight gap is generated between the divided punches. When compressing the raw material powder, if the raw material powder enters the gap between the divided punches, or if the press surfaces of the divided punches do not match, the rake face 3 of the formed throw-away tip has a chip A step portion 10 is formed on the surface of the rake face 3 over the thickness direction of the main body, and the step portion 10 reaches the cutting edges 4 formed at both ends of the rake face 3 in the thickness direction. Therefore, there is a problem that the stepped portion 10 is also formed on a part of the cutting edge 4.
That is, the stepped portion 10 formed on the cutting edge 4 may damage the surface of the work material when the cutting edge 4 cuts the work material, and the accuracy of the finished surface of the work material surface may deteriorate. There is a problem, and there is a problem in that excessive stress is concentrated on the stepped portion 10 at the time of cutting, and the cutting edge may be chipped from the stepped portion 10 as a starting point.

    The present invention has been made in consideration of such circumstances, and its purpose is to adjust the filling ratio of the raw material powder filled in the cavity and to form a step portion formed on the rake face of the cutting blade member. By preventing the cutting edge from extending to the cutting edge, it is possible to prevent the formation of a stepped portion on the cutting edge, thereby improving the finished surface accuracy of the work material and the tool life of the insert body. It is an object of the present invention to provide a method for manufacturing a cutting blade member of a cutting tool capable of performing the above and a green compact press molding die used in the manufacturing method.

In order to achieve the above object, the present invention provides the following means.
According to the first aspect of the present invention, a plurality of punches which are opposed to each other and relatively separated from each other, and a cavity which is disposed so as to surround the peripheries of these adjacent punches, is defined. Cutting which press-molds the green compact produced on the cutting blade member of a cutting tool by compressing the raw material powder charged into the cavity with the punch using a press-molding die having a die to be formed In the method for manufacturing a cutting edge member of a tool, a plurality of divided punches, wherein at least one of the plurality of punches is divided with a divided surface extending in a direction of separating the punch when the raw material powder is compressed. The portion corresponding to at least one continuous cutting blade portion of the cutting blade member is formed by one divided punch among the divided punches.

    According to the method for manufacturing a cutting blade member of a cutting tool according to the present invention, when a green compact is formed in which a raw material powder is compressed into a cutting blade member in the cavity, Since one of the punches is divided by a plurality of divided punches having a dividing surface extending in the direction of separation, the filling ratio in the green compact can be adjusted satisfactorily. Since one of the divided punches forms one continuous cutting edge portion of the cutting blade member, the boundary portion between the one divided punch and the other divided punch, that is, the butted portion between the divided surfaces is the cutting blade member. Therefore, the cutting blade of the cutting blade member is accurately formed without forming the continuous cutting blade.

    According to a second aspect of the present invention, in the method for manufacturing a cutting blade member of a cutting tool according to the first aspect, another divided punch is disposed inside the one divided punch, and the cutting blade portion is arranged. All the parts corresponding to the continuous outer peripheral ridgeline of the green compact are formed by the one divided punch.

    According to the method for manufacturing the cutting blade member of the cutting tool according to the present invention, since the other divided punch is positioned inside the one divided punch, the other divided punch is disposed on the outer peripheral edge portion of the one divided punch. When the cutting blade member is formed by compressing the raw material powder in the cavity without being positioned, the outer peripheral edge portion of one divided punch accurately forms the outer peripheral edge portion of the cutting blade member.

    According to a third aspect of the present invention, in the method for manufacturing a cutting blade member of the cutting tool according to the first or second aspect, the green compact has a flat plate shape and is arranged around the flat plate surface. At least one of the peripheral surfaces to be formed is compressed by a punch constituted by the plurality of divided punches.

    According to the method for manufacturing a cutting blade member of a cutting tool according to the present invention, a cutting blade member such as the vertical blade type throwaway tip having a flat plate surface and a rake face arranged around the flat plate surface is obtained. A green compact is formed, and a punch constituted by a plurality of divided punches forms a portion that becomes at least one rake face of the cutting blade member.

    According to a fourth aspect of the present invention, in the method for manufacturing a cutting edge member of the cutting edge tool according to the third aspect, the pin is capable of protruding and retracting in the direction perpendicular to the separation / contact direction of the punch in the cavity. A hole is formed in the flat plate surface of the green compact.

  According to the method for manufacturing a cutting blade member of a cutting tool according to the present invention, in the vertical blade type throwaway tip, the green compact which is a cutting blade member having a through-hole formed in a flat plate surface has a filling ratio. Molded without bias.

  A fifth aspect of the present invention is a green compact press mold used in the method for manufacturing a cutting blade member of a cutting tool according to any one of the first to fourth aspects, wherein the pressing molds are opposed to each other. A plurality of punches that are relatively separated from each other, and a die that is disposed so as to surround the peripheries of the punches that are close to each other and that defines a cavity between the punches. One is a split punch that slides along the peripheral surface in the cavity, and another split punch that is slidably fitted in a through-hole formed in the one split punch. A plurality of divided punches are provided.

  According to the press molding die of the green compact according to the present invention, when the raw material powder is compressed in the cavity and the cutting blade member is molded, the outer peripheral edge of one divided punch and the inner cavity The peripheral surface cooperates to form a portion corresponding to the outer peripheral edge portion including the cutting edge portion of the cutting blade member, and one divided punch and the other divided punch are located inside the outer peripheral edge portion of the rake face. The part corresponding to is molded. The one divided punch in the method for manufacturing a cutting blade member of the cutting tool and the green compact press mold of the present invention is at least one continuous cutting blade of the cutting blade member among the plurality of divided punches. One divided punch with respect to another divided punch that does not mold a portion corresponding to the portion, and the portion where this one divided punch is not used as a cutting blade, and further constituted by a plurality of divided punches In this case, the through hole only needs to be formed in one divided punch constituted by the plurality of divided punches.

  The invention described in claim 6 is characterized in that, in the green compact press-molding die described in claim 5, the other divided punch is further constituted by a plurality of divided punches.

  According to the powder press die according to the present invention, since the other divided punch is constituted by a plurality of divided punches, the filling ratio of the raw material powder filled in the cavity can be adjusted even better. it can.

  According to a seventh aspect of the present invention, in the green compact press molding die according to the fifth or sixth aspect, the area of the press surface of the other divided punch is the same as that of the press surface of the one divided punch. Of the line segments forming the contour of the press surface of the other divided punch, the line segment that does not extend along the outer peripheral edge portion, and the extension line to the outer peripheral edge portion is surrounded. It is characterized by being 50% or more of the area.

According to the green compact press-molding die according to the present invention, a sufficient area is secured on the press surface of the other divided punch to adjust the filling amount of the raw material powder in the punch separation / contact direction in the cavity. Therefore, the density in the formed cutting blade member becomes uniform.
The area of the press surface of the other divided punch is the outer peripheral edge of the outer peripheral edge of the press surface of the one divided punch and the line segment forming the contour of the press surface of the other divided punch. When the area is smaller than 50% of the area surrounded by the line segment that does not extend along the line and the extension line to the outer peripheral edge, the other split punch is in the direction of the punch separation / contact of the raw material powder in the cavity. It becomes difficult to adjust the filling amount in the orthogonal direction, and it becomes difficult to make the density of the formed cutting blade member uniform.
However, if this area is too large, there is a possibility that the sufficient width between the through-hole and the outer peripheral edge described below cannot be secured.

  According to an eighth aspect of the present invention, in the green compact press molding die according to the seventh aspect, the area of the press surface of the other divided punch is the outer peripheral edge of the press surface of the one divided punch. And the area surrounded by the line segment that does not extend along the outer peripheral edge portion and the extended line to the outer peripheral edge portion among the line segments that form the contour of the press surface of the other split punch It is characterized by being 80% or more.

  According to the powder molding press according to the present invention, the adjustment of the filling ratio of the raw material powder filled in the cavity is more reliably achieved.

  According to a ninth aspect of the present invention, in the green compact press-molding die according to any one of the fifth to eighth aspects, the through-hole formed in the one divided punch is the one divided It is characterized by being formed at a position spaced 0.1 mm or more from the outer peripheral edge of the punch.

According to the green compact press die according to the present invention, the width between the through hole formed in one divided punch and the outer peripheral surface slidably contacting the inner peripheral surface of the cavity is formed to be 0.1 mm or more. Therefore, one divided punch has a strength that does not break even if the forming of the cutting blade member is repeated.
However, if this width is too wide, the press surface of the other divided punch becomes small, and it becomes difficult to adjust the filling ratio of the raw material powder filled in the cavity. It is desirable.

  According to a tenth aspect of the present invention, in the green compact press molding die according to the ninth aspect, the through hole is formed at a position spaced 0.5 mm or more away from the outer peripheral edge of the one divided punch. It is characterized by being.

  According to the green compact press die according to the present invention, one divided punch surely has a strength that does not break even when the cutting blade member is repeatedly formed.

  According to an eleventh aspect of the present invention, in the green compact press-molding die according to any one of the fifth to tenth aspects, a through hole into which the other divided punch is inserted is provided in the one divided punch. It is formed in one place.

  According to the green compact press die according to the present invention, since there is one through-hole formed in one divided punch, a punch constituted by one divided punch and another divided punch is easy and It is manufactured with high accuracy. In addition, for example, when forming a green compact manufactured on the above-mentioned vertical blade type throw-away tip, the finish surface accuracy of the work surface is affected when cutting with the throw-away tip. Since the corner portion of the rake face around the corner portion can be formed by a single split punch, the throwaway tip (cutting blade member) manufactured in this way has higher processing accuracy. Can be obtained.

According to a twelfth aspect of the present invention, in the green compact press-molding die according to any one of the fifth to eleventh aspects, at least one of the plurality of punches configured by the plurality of divided punches. The press surface of the punch is formed with an uneven portion that is concave or convex relative to the adjacent portion in the direction of separation of the punch, and the dividing lines of the plurality of divided punches are It is formed along a boundary part with the adjacent part.
According to the green compact press die according to the present invention, for example, among cutting members to be molded, the surface formed by one divided punch and the other divided punch is recessed along the outer peripheral edge. When the breaker is formed, the stepped portion formed by the dividing line of one divided punch and the other divided punch is formed at the bottom of the breaker or at the opening edge of the breaker. Even if it occurs, the influence on the flow of chips generated during cutting can be suppressed, and abnormal phenomena such as chip catching can be suppressed.

  According to the present invention, by preventing the step portion formed on the rake face of the cutting blade member from extending to the cutting blade, it is possible to prevent the step portion from being formed on the cutting blade. The finished surface accuracy of the work material and the tool life as a cutting blade member can be improved.

1 is a perspective view of a green compact press-molding die according to a first embodiment of the present invention. FIG. FIG. 2 is a perspective view of a throw-away tip formed by the green compact press-molding die shown in FIG. 1. FIG. 2 is a top view of a lower punch of a green compact press molding die shown in FIG. 1. It is a perspective view at the time of the press molding die of the green compact shown in FIG. 1 compressing raw material powder. It is a perspective view of the press molding die of the green compact concerning a 2nd embodiment of this invention. (A) It is a perspective view of the throw away tip shape | molded by the press molding die of the compact shown in FIG. 5, (b) It is a partial expanded sectional view of Fig.6 (a). FIG. 6 is a top view of the lower punch of the green compact press-molding die shown in FIG. 5. It is a partial enlarged view of the outer side division punch which comprises a lower punch. It is a partially enlarged view of the outer divided punch and the inner divided punch constituting the lower punch. (A) It is a perspective view of the press molding die of the green compact concerning the 3rd Embodiment of this invention, (b) It is a bottom view of the upper punch 21 of (a). (A) It is a top view of the throw away tip shape | molded by the press molding die of the compact shown in FIG. 10, (b) It is a side view of the throw away tip shown in (a). (A) It is a perspective view of the press molding die of the green compact concerning 4th Embodiment, (b) It is a top view of the lower punch shown by (a). (A) It is a perspective view of the throw away tip shape | molded by the press molding die of the compact shown in FIG. 12, (b) It is a top view of (a). It is a perspective view of the press molding die of the green compact concerning the 5th Embodiment of this invention. FIG. 15 is a perspective view of a throw-away tip formed by the green compact press-molding die shown in FIG. 14. FIG. 15 is a top view of the lower punch of the green compact press-molding die shown in FIG. 14. (A) It is a perspective view of the press molding die of the green compact concerning 6th Embodiment of this invention, (b) It is a bottom view of the upper punch 21 of (a). (A) It is a top view of the throw away tip shape | molded with the press molding die of the compact shown in FIG. 17, (b) It is a side view of (a). It is a perspective view of the press-molding die of the green compact concerning a 7th embodiment of this invention. FIG. 20 is a top view of the lower punch of the green compact press mold shown in FIG. 19. It is a top view of the lower punch 22 of the press molding die of the green compact concerning the 8th Embodiment of this invention. FIG. 22 is a perspective view of a throw-away tip formed by the green compact press-molding die shown in FIG. 21. (A) It is a top view of the lower punch 22 of the press molding die of a green compact. (B) It is a top view of the lower punch 22 of the press molding die of a green compact. It is a top view which shows the modification of the lower punch shown by FIG. It is a perspective view of a throw-away tip molded by a conventional green compact press mold. FIG. 6 is a perspective view of a conventional green compact press mold.

Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a view showing a green compact press-molding die according to the present embodiment. The cutting blade of the cutting tool of the present invention using the press-molding die will be described below while explaining the press-molding die. An embodiment of a member manufacturing method will also be described.
A press-molding die 20 shown in FIG. 1 is for molding a green compact to be formed on a vertical blade type throw-away tip 50 shown in FIG. 2, and as shown in FIG. The molding die 20 includes upper and lower punches 21 and 22 that are supported so as to be relatively separable from each other in a vertical direction that is perpendicular to a direction corresponding to the thickness direction of the chip body, and an upper punch 21 and a lower punch. The die 23 is disposed so as to surround the periphery of the upper punch 21 and defines the cavity A between the upper punch 21 and the lower punch 22, and the thickness direction of the lower punch 22 (in FIG. 1, from the left front to the right It is comprised from the pin 24 provided in the cavity A toward the back (it is only called a punch thickness direction hereafter).

The lower punch 22 includes an outer divided punch (one divided punch) 25 and an inner divided punch 26 (another divided punch) that is fitted in the outer divided punch 25 and is slidable in the vertical direction. Yes.
The outer divided punch 25 is fixed to the outer punch plate 27, and a through hole 25a into which the inner divided punch 26 is inserted is formed at the center of the outer divided punch 25. Accordingly, the inner peripheral surface of the through hole 25a is a divided surface on the outer divided punch 25 side, and the outer peripheral surface of the inner divided punch 26 inserted into the through hole 25a is the divided surface.
As shown in FIG. 3, the press surface 25A at the upper end surface of the outer divided punch 25 includes a ridge line portion (line segment) 25A1 arranged in parallel to the punch thickness direction, and a ridge line portion 25A2 orthogonal to the ridge line portion 25A1. It is made into the substantially rectangular shape comprised from these. Further, the corner portion of the ridge line portion 25A1 and the ridge line portion 25A2 is a 1/4 convex arc-shaped corner portion 25A3.
The through hole 25 a is formed in the substantially central portion of the press surface 25 </ b> A of the outer divided punch 25.
Both end portions of the through hole 25a in the punch thickness direction are formed at positions spaced from the ridge line portion 25A2 of the outer divided punch 25 by 0.1 mm or more (preferably 0.5 mm or more).
That is, the width of the thin portion 25b formed between the peripheral surfaces facing each other in the punch thickness direction in the inner peripheral surface of the through hole 25a and the outer peripheral surface of the outer divided punch 25 is 0.1 mm or more. It is configured as follows.

The inner divided punch 26 is fitted into a through hole 25a formed in the outer divided punch 25, and is fixed to the inner punch plate 28 as shown in FIG. 26 </ b> A is arranged so as to protrude above the press surface 25 </ b> A on the upper end surface of the outer divided punch 25.
In FIG. 3, the outer peripheral edge portion of the press surface 26A of the inner divided punch 26 is a ridge line portion 26a, 26a parallel to the punch thickness direction, and a ridge line portion orthogonal to the ridge line portion 26a and parallel to the ridge line portion 25A2. 26b, 26b, and is formed in a substantially square shape.
Among these, the ridge lines 26a and 26a are configured to coincide with both side edges of the pin 24 when viewed from above.
The area I1 of the press surface 26A of the inner divided punch 26 is a ridge line that forms the contour of the outer peripheral edge of the press surface 25A on the upper end surface of the outer divided punch 25 and the press surface 26A of the inner divided punch 26 when viewed from above. Area O1 (which is surrounded by ridge line portions 26a, 26a that do not extend along the outer peripheral edge portion of the press surface 25A, and an extension line of the ridge line portions 26a, 26a to the outer peripheral edge portion of the press surface 25A ( 50% or more (preferably 80% or more) of the area of the hatched portion in FIG.
A slight gap is generated between the inner divided punch 26 and the outer divided punch 25, and a dividing line 80 between the inner divided punch 26 and the outer divided punch 25 by the gap, that is, the above-described division of each other. Intersecting ridgelines between the surface and the press surfaces 25 </ b> A and 26 </ b> A are formed along the outer peripheral edge of the inner divided punch 26.
In FIG. 1, the outer punch plate 27 and the inner punch plate 28 are displaced in the vertical direction perpendicular to the punch thickness direction by a drive source (not shown).

The cavity A formed in the die 23 includes an inner peripheral surface 23A disposed substantially parallel to the punch thickness direction, an inner peripheral surface 23B disposed in a direction substantially orthogonal to the inner peripheral surface 23A, and an inner peripheral surface It is composed of a convex curved surface 23C that is formed at a crossing ridge line portion between the surface 23A and the inner peripheral surface 23B and is formed in a ¼ convex arc shape in cross section.
The pin 24 is formed in a cylindrical shape, and is provided in the cavity A so as to be able to advance and retreat in the punch thickness direction.

The upper punch 21 has the same configuration as the lower punch 22, and has an outer divided punch (one divided punch) 31 and an inner divided punch that is fitted in the outer divided punch 31 and is slidable in the vertical direction. 32 (other divided punches).
The outer divided punch 31 is fixed to the outer punch plate 33, and a through hole 31 a into which the inner divided punch 32 is inserted is formed at the center of the outer divided punch 31.
The press surface 31A of the outer divided punch 31 has the same shape as the press surface 25A of the outer divided punch 25.
The through hole 31 a is formed at a substantially central portion of the press surface 31 A of the outer divided punch 31, and is formed at the same position as the through hole 25 a formed in the outer divided punch 25.
The inner divided punch 32 is fitted into a through hole 31 a formed in the outer divided punch 31 and is fixed to the inner punch plate 34. The press surface 32 A of the inner divided punch 32 is the press surface 31 A of the outer divided punch 31. It arrange | positions so that it may protrude below.
Further, the press surface 32A of the inner divided punch 32 has the same shape as the press surface 26A of the inner divided punch 26.

In order to produce a green compact to be formed into a vertical blade type throw-away tip by the press molding die 20 configured in this way, first, raw material powder is filled into the cavity A in the filling step. .
When the raw material powder is filled into the cavity A, before the upper punch 21 is inserted into the cavity A, a cemented carbide containing WC as a main component from the opening is inserted. Raw material powder for throwaway chips such as cermet mainly composed of TiC-TiN is charged. When the raw material powder is put into the cavity A, the press surface 26A of the inner divided punch 26 is positioned above the press surface 25A of the outer divided punch 25, and the pin 24 is In the cavity A, it arrange | positions toward the punch thickness direction.

Next, in the filling ratio adjustment step of adjusting the filling ratio of the raw material powder in the cavity A, the upper punch 21 is inserted from the upper opening portion of the cavity A, and the inner divided punch 32 is driven to press the press surface 32A. Is protruded from the press surface 31A of the outer divided punch 31 and at the same time, the inner divided punch 26 is pulled into the outer divided punch 25, whereby the raw material powder immediately above the pin 24 is pushed by the inner divided punch 32, By pulling in the inner divided punch 26, the raw material powder is sucked into the portion directly under the pin 24, and the raw material powder in the cavity A is regulated so as to restrict the density of the raw material powder in the portion directly under the pin 24. The filling ratio is adjusted.
At this time, as shown in FIG. 3, the area I1 of the press surface 26A of the inner divided punch 26 is equal to the outer peripheral edge of the press surface 25A on the upper end surface of the outer divided punch 25 and the inner divided punch when viewed from above. Among the ridge lines that form the contour of the press surface 26A of 26, the ridge line portions 26a and 26a that do not extend along the outer peripheral edge of the press surface 25A and the extension line to the outer peripheral edge of the press surface 25A are surrounded. Since the inner divided punch 26 is drawn into the outer divided punch 25, the raw material powder immediately below the pin 24 is sucked in well, and the inside of the cavity A is The filling ratio of the raw material powder is adjusted favorably.
Further, when the area I1 is configured to be 80% or more with respect to the area O1 (the area of the hatched portion in FIG. 3), the filling ratio of the raw material powder is adjusted more satisfactorily.
However, if the area ratio becomes too large, the width of the thin portion 25b described above may become too small.

  Next, in the pressurizing step after the filling ratio adjusting step, as shown in FIG. 4, the lower punch 22 matches the press surfaces 25 </ b> A and 26 </ b> A of the outer divided punch 25 and the inner divided punch 26. On the other hand, in the upper punch 21, the upper punch 21 and the lower punch 22 are close to each other so that the press surfaces 31 </ b> A and 32 </ b> A of the inner divided punch 32 and the outer divided punch 31 coincide with each other, and compress the raw material powder.

When the upper and lower punches 21 and 22 compress the raw material powder, a portion corresponding to the rake face 53 of the throw-away tip 50 is formed, and the inner peripheral surface 23B of the cavity A corresponds to the flat plate surface 52 of the throw-away tip 50. The portion is formed, and further, the portion corresponding to the peripheral surface 55 of the throw-away tip 50 is formed by the inner peripheral surface 23A of the cavity A.
The pin 24 disposed in the cavity A in the punch thickness direction forms a portion corresponding to the hole 59 penetrating in the thickness direction of the chip body at a substantially central portion of the flat plate surface 52 to be formed.

When the lower punch 22 forms one rake face 53 of the pair of rake faces 53, the ridge line portion 25A1 of the press face 25A and the inner peripheral face 23A of the cavity A cooperate with each other to insert a throw-away tip. A portion corresponding to 50 cutting blades 56 is formed.
Further, the ridge line portion 25A2 of the press surface 25A and the inner peripheral surface 23B of the cavity A cooperate to form a portion corresponding to the cutting edge 54 of the throw-away tip 50.
Further, the corner portion 25A3 of the press surface 25A and the convex curved surface 23C of the cavity A cooperate to form a portion corresponding to the corner portion 57 of the throw-away tip 50.
That is, a portion corresponding to the outer peripheral edge portion of the rake face 53 of the throw-away tip 50 is formed by the outer divided punch 25 and the inner peripheral face of the cavity A. On the other hand, the press surface 26 </ b> A of the inner divided punch 26 forms a portion of the rake surface 53 of the throw-away tip 50 corresponding to the inside of the cutting edge portions 54 and 56.

  When the press surface 26A of the inner divided punch 26 forms a portion corresponding to a part of the rake face 53, raw material powder enters between the inner divided punch 26 and the outer divided punch 25, or the press surface. Since the 25A and the press surface 26A are not located at the same position, the stepped portion 70 along the dividing line 80 between the inner divided punch 26 and the outer divided punch 25 may be formed on the formed rake face 53. However, at this time, the ridge line portions 26 a and 26 b of the inner divided punch 26 are positioned inward from the ridge line portions 25 A 1, 25 A 2, and 25 A 3 of the outer divided punch 25, so that they follow the outer peripheral edge of the inner divided punch 26. The dividing line 80 is also positioned inward of the ridge line portions 25A1, 25A2, and 25A3 of the outer dividing punch 25, and is formed on the rake face 53 of the throw-away tip 50. Difference portion 70 is formed inward from the outer peripheral ridge portions of the rake face 53.

  Thus, when the upper and lower punches 21 and 22 compress the raw material powder, the flat plate surfaces 52 and 52 and the flat plate surface 52 are disposed in the cavity A so as to face the punch thickness direction as shown in FIG. The green compact formed on the throw-away tip 50 composed of the rake face 53 formed by the upper and lower punches 21 and 22 and the remaining pair of other peripheral faces 55 is formed.

  In the pin extracting step after the pressing step, the pressurization of the upper and lower punches 21 and 22 with respect to the formed green compact is reduced or removed. However, the upper punch 21 is not separated from the green compact, but the green compact is sandwiched between the upper and lower punches 21 and 22. Thus, since the upper and lower punches 21 and 22 reduce or eliminate the pressure applied to the green compact, no load is applied when the pin 24 is removed, and in particular, the green compact in which the hole 59 is formed. There is no crushing.

In the extraction step after the pin extraction step, the die 23 is displaced downward until the upper end of the lower punch 22 coincides with the upper surface of the die 23 with the green compact sandwiched between the upper and lower punches 21 and 22. As a result, the green compact is extracted from the cavity A of the die 23, and then the upper punch 21 is pulled away from the green compact, whereby the green compact is discharged from the lower punch 22 and the green compact is removed. It is taken out. Thus, since the upper end of the lower punch 22 is made to coincide with the upper surface of the die 23, it is easy to discharge the green compact.
In this extraction step, the press surfaces 31A and 32A of the inner split punch 32 and the outer split punch 31 are matched, and the press surfaces 26A and 25A of the inner split punch 26 and the outer split punch 25 are matched. Is held by.

In the pin insertion step after the extraction step, the die 23 that has been displaced downward during the extraction step is displaced upward, and the inner divided punch 26 is protruded from the outer divided punch 25. Then, the pin 24 is inserted into the cavity A.
Thereby, the filling process of filling the raw material powder is enabled.

In such a method for manufacturing the throw-away tip 50 and the press molding die 20, even when the stepped portion 70 is formed in a portion corresponding to the rake face 53 of the throw-away tip 50 to be molded, it is formed. It is possible to reliably prevent the stepped portion 70 from being formed on the ridge line portion of the rake face 53.
For this reason, even when the formed green compact is subsequently sintered and the throw-away tip 50 is formed, the stepped portion 70 is formed at the cutting edges 54 and 56 and the corner portion 57 formed on the rake face 53. When the workpiece is machined by the throw-away tip 50, the stepped portion 70 is formed at a position separated from the cutting blades 54 and 56 and the corner portion 57. Therefore, the finished surface is prevented from being deteriorated by the stepped portion 70 without contacting the surface of the work material, and a good finished surface can be obtained.
In particular, the most important corner portion 57 at the time of cutting is formed by the single outer divided punch 25, so that it can be accurately formed as specified.
Further, since the stepped portion 70 does not come into contact with the cutting surface, it is possible to prevent an excessive load from being applied to the stepped portion 70 and to prevent the throw-away tip 50 from being damaged starting from the stepped portion. it can.

In addition, since the width of the thin portion 25b formed in the outer divided punch 25 is configured to be 0.1 mm or more, the thin portion 25b is cracked or chipped even if the green compact is repeatedly formed. Therefore, the green compact can be molded satisfactorily. In particular, when the width of the thin portion 25b formed on the outer divided punch 25 is 0.5 mm or more, the thin portion 25b can be surely provided with a strength that does not cause cracks or defects. it can.
However, if the width becomes too large, the area of the press surface 26A of the inner divided punch 26 becomes small, and it may be difficult to adjust a good filling ratio.
Furthermore, according to this embodiment, since the through holes 25a, 31a formed in the outer divided punches 25, 31 are only formed in one place, any of the upper punch 21 and the lower punch 22 is selected. Can be accurately and easily formed. In addition, in the case of molding the green compact manufactured on the vertical blade type throw-away tip 50 as in the present embodiment, the through holes 25a and 31a are formed at the center portions of the press surfaces 25A and 31A of the outer divided punches 25 and 31. 2, the stepped portion 70 is positioned at the center of the rake face 53 as shown in FIG. 2, and the finished surface of the work material is formed by cutting with the throwaway tip 50. The rake face 53 around the corner portion 57 important for shape accuracy can be formed by press molding with the press surfaces 25A and 31A of the single outer divided punches 25 and 31, respectively. It becomes possible to give high accuracy, and it is possible to manufacture the throw-away tip 50 that can be processed with high accuracy.

A second embodiment of the present invention will be described with reference to FIGS. In addition, about the same structure as the structure shown by FIGS. 1-4, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
FIG. 5 is a view showing a press-molding die 20 according to the second embodiment. As shown in FIG. 6A, the green compact formed on the throw-away tip 50 on which the breaker 60 is formed. Is formed.
As shown in FIG. 6B, the breaker 60 formed in the vicinity of the outer peripheral edge of the rake face 53 of the slow way tip 50 is formed in an annular shape along the outer peripheral edge of the rake face 53.
Further, the breaker 60 is connected to the inclined surface 60a gradually toward the inner side of the main body of the throwaway tip 50 as it goes inward from the outer peripheral edge side of the rake face 53, and the outer peripheral edge side of the rake face 53. It is comprised from the inclined surface 60b which inclines toward the outer side of the slow way chip | tip 50 gradually as it goes inside. The intersecting ridge line portion between the inclined surface 60a and the inclined surface 60b is a smooth concave curved surface portion 60c.
A cutting edge land 62 formed in a flat shape is formed on the outer peripheral edge of the breaker 60, and a flat seating surface 63 is formed on the chip body side from the breaker 60.

As shown in FIG. 5 and FIG. 7 when the lower punch 22 is viewed from above, an annular convex portion 30 is formed on the outer peripheral edge portion of the press surface 25A of the outer divided punch 25.
FIG. 8 is an enlarged view of the cross section Q in FIG. 7. As shown in FIG. 8, a flat surface 31 is formed on the outer peripheral edge of the press surface 25 </ b> A. Is formed with an annular convex portion 30 composed of a raised surface 32 that gradually rises inward from the flat surface 31 and a descending surface 33 that gradually descends inward from the raised surface 32. A flat surface 34 is formed inside 30. The intersecting ridge line portion 35 between the raised surface 32 and the descending surface 33 is a smooth convex curved surface.

As shown in FIGS. 5 and 7, the ridge line portion 26 b of the press surface 26 </ b> A of the inner divided punch 26 is formed with a protruding portion 38 that protrudes upward, and this protruding portion 38 is an outer peripheral edge portion. Is formed by a descending surface 36 that gradually descends as it goes in the punch thickness direction.
9 is a partially enlarged view of the cross section P in FIG. 7. As shown in FIG. 9, the ridge line portion 26b of the inner divided punch 26 is positioned at the intersecting ridge line portion 35 of the outer divided punch 25. As shown in FIG. The descending surface 36 is formed to have the same gradient as the descending surface 33 of the outer divided punch 25. A flat surface 37 is formed on the inner side of the descending surface 36.
That is, as shown in FIG. 7, a part of the annular protrusion 30 is formed with a part of the through hole 25 a into which the inner divided punch 26 is inserted, and the ridge line part 26 b of the inner divided punch 26 is formed on the outer side. A part of the annular convex portion formed in the divided punch 25 is constituted. The upper punch 21 has the same configuration as the lower punch 22.
Accordingly, the press surface of the lower punch 22 has a concave portion or a descending surface 36 that is concave relative to an adjacent portion, for example, the raised surface 32 in the separating direction of the lower punch 22 (vertical direction in FIG. 9). The dividing line of the plurality of divided punches (the outer divided punch 25 and the inner divided punch 26), that is, the ridge line portion 26b is formed along the boundary portion between the concave portion and the adjacent portion, that is, the intersecting ridge line portion 35. Will be. On the contrary, when the descending surface 36 is the adjacent portion, the raised surface 32 is a convex portion that is relatively convex in the direction of contact with the lower punch 22, and the ridge line portion 26b is the convex portion. And the intersection ridge line portion 35 which is a boundary portion between the adjacent portions.

In the press molding die 20 configured as described above, when the lower punch 22 compresses the raw material powder and molds the portion corresponding to the rake face 53 of the throw-away tip 50 in the pressurizing step, the outer division is performed. The annular convex portion 30 of the punch 25 and the protruding portion 38 of the inner divided punch 26 cooperate to form a portion to be the breaker 60 of the throw-away tip 50 as shown in FIG.
The flat surface 31 forms a portion corresponding to the cutting edge land 62 of the throw-away tip 50, and the flat surfaces 34 and 37 shape portions corresponding to the seating flat surface 63 of the throw-away tip 50.
At this time, the raw material powder enters the gap between the inner divided punch 26 and the outer divided punch 25, or the inner divided punch 26 and the outer divided punch 25 are not positioned at the same position, so that the throw-away tip 50 is formed. Both end portions of the stepped portion 70 in the punch thickness direction are formed at portions that are the concave curved surface portions 60 c of the breaker 60.

The green compact formed in this manner is then sintered to form a throw-away tip 50.
When the throwaway tip 50 is mounted on the tool body and the work material 81 is cut as shown in FIG. 6B, the chips 82 of the work material 81 are bent by the inclined surface 60a. And is cut by being brought into contact with the inclined surface 60b.
For this reason, the chips 82 of the cutting material 81 do not easily enter the concave curved surface portion 60c of the breaker 60, and the stepped portion 70 does not interfere with the cutting of the chips 82, and the chips 82 are discharged outwardly.
Thus, according to the present embodiment, it is possible to obtain a throw-away tip with a breaker that can cut the chips 82 well and discharge them outward.

In the present embodiment, the position of the ridge line portion 26b of the inner divided punch 26 is positioned at the intersecting ridge line portion 35 of the outer divided punch 25. However, the present invention is not limited to this.
For example, the position of the ridge line portion 26b of the inner divided punch 26 may be positioned at the intersection ridge line portion of the flat surface 31 and the raised surface 32 of the outer divided punch 25 in FIG. You may be located in the intersection ridgeline part.
In particular, when the ridge line portion 26 b of the inner divided punch 26 is positioned at the intersecting ridge line portion of the descending surface 33 and the flat surface 34 of the outer divided punch 25, a step portion formed on the rake face 53 of the throw-away tip 50. Both end portions in the chip thickness direction of the chip 70 are formed on the ridge line between the seating flat surface 63 and the breaker 60. Since the seating flat surface 63 is polished thereafter, the stepped portion 70 is surely removed. can do.
Also in this embodiment, since it is configured in the same manner as in the first embodiment, the same actions and effects as in the first embodiment can be obtained.

A third embodiment according to the present invention will be described with reference to FIGS. In addition, about the structure same as the structure shown by FIGS. 1-9, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
As shown in FIG. 10 (a), the press-molding die 20 according to the present embodiment forms a throw-away tip 90 for a ball end mill, as shown in FIGS. 11 (a) and 11 (b). The throw-away tip 90 includes a leaf-like flat plate surface 92 on which an arcuate cutting edge 91 is formed, a lower surface 93 opposed to the flat plate surface 92 in the chip thickness direction, and a periphery of the flat plate surface 92. And a peripheral surface 94.
The flat plate surface 92 is formed at the center of the flat plate surface 92 and is parallel to the lower surface 93. The flat plate surface 92 is disposed on both sides of the flat portion 92a and extends from the flat portion 92a toward the tip side of the cutting blade 91. The flat surface 92a is formed with a hole 95 penetrating from the flat plate surface 92 to the lower surface 93. The inclined surface 92b and 92b are gradually inclined toward the lower surface 93 side.

As shown in FIG. 10A, the press mold 20 is provided in the cavity A, the upper and lower punches 21 and 22 that are separated from each other in the vertical direction, the die 23 in which the cavity A is formed, and the cavity A. It consists of pins 24.
As shown in FIGS. 10A and 10B, the upper punch 21 includes an outer divided punch 31 and an inner divided punch 32.
The outer divided punch 31 has a leaf-like cross section perpendicular to the sliding direction of the upper punch 21, and a through hole 31 a is formed at the center of the lower end.
The central portion of the outer divided punch 31 is a flat surface 41 in which a through-hole 31a is formed, and inclined surfaces 42, 42 that gradually protrude downward toward the tip on both sides of the flat surface 41. Is formed.
The outer peripheral edge portion of the outer divided punch 31 includes a curved portion 42a that curves outward and a straight portion 42b that intersects the curved portion 42a.
The through hole 31 a is formed at a position spaced from the outer peripheral edge of the outer divided punch 31 by 0.1 mm or more (preferably 0.5 mm or more).
For this reason, the dividing line 80 between the outer divided punch 31 and the inner divided punch 32 is arranged inside the outer peripheral edge of the lower end surface of the outer divided punch 31.
The inner divided punch 32 is fitted into a through hole 31 a formed in the outer divided punch 31, and a pin 60 that replaces the pin 24 is provided on the lower end surface thereof. The lower end surface of the inner divided punch 32 that is the press surface 32A is a flat surface.
When the inner divided punch 32 is viewed from the bottom surface of the upper punch 21, the area I1 of the inner divided punch 32 constitutes the outer peripheral edge of the outer divided punch 31 and the outer peripheral edge of the flat surface 32A of the inner divided punch 32. 50% or more of the area O1 (the area of the hatched portion in FIG. 10B) surrounded by the ridge line part that does not follow the outer peripheral edge part of the outer divided punch 31 and the extension line of the ridge line part among the ridge line parts to be performed ( Preferably, it is formed to be 80% or more.

The lower punch 22 includes an outer divided punch 25 and an inner divided punch 26.
The outer divided punch 25 is formed in a leaf shape when viewed from above, and the upper end surface is a flat surface. A through hole 25a is formed at the center of the outer divided punch 25, and an inner divided punch 26 is inserted into the through hole 25a.
The cylindrical pin 24 is fitted into the inner divided punch 26 and is supported in the cavity A so as to be movable up and down.
The cavity A formed in the die 23 is formed in a leaf shape when viewed from above, and the inner peripheral surface thereof is curved surface portions 45a and 45a that are curved outward, the curved surface portion 45a, It is comprised from the plane parts 45b and 45b provided in a row by 45a.

In the press molding die 20 configured in this way, when the upper and lower punches 21 and 22 compress the raw material powder filled in the cavity A in the pressurizing step, the throw-away for the ball end mill shown in FIG. The green compact formed on the chip 90 is formed.
In this pressurizing step, the raw powder is compressed in a state where the flat surface 41 of the outer divided punch 31 of the upper punch 21 and the press surface 32A of the inner divided punch 32 are made to coincide with each other. A portion corresponding to the flat portion 92a of the flat plate 92 is formed, and the portion corresponding to the flat plate 92 is formed by forming the portion where the inclined surface 42 of the outer divided punch 31 corresponds to the inclined surface 92b of the throw-away tip 90. Molded.

Further, the curved portion 42a formed on the inclined surface 42 of the outer divided punch 31 and the curved surface 45a of the cavity A cooperate to form a portion corresponding to the cutting edge 91 of the throw-away tip 90. .
At this time, since the dividing line 80 between the outer divided punch 31 and the inner divided punch 32 is not positioned at the curved portion 42a of the outer divided punch 31, the portion corresponding to the cutting edge 91 of the throw-away tip 90 is a single part. It is comprised by the outer side division punch 31 made into this structure.
That is, the raw material powder enters the dividing line between the outer divided punch 31 and the inner divided punch 32, or the raw material powder is compressed in a state where the lower end surfaces of the outer divided punch 31 and the inner divided punch 32 do not match. As a result, the stepped portion 70 formed on the throw-away tip 90 is formed inside the outer peripheral edge of the flat plate 92 of the throw-away tip 90.
As described above, the stepped portion 70 is not formed on the cutting edge 91 and has the same configuration as that of the first embodiment. Therefore, the same operations and effects as those of the first embodiment are used. Can be obtained. In particular, also in the present embodiment, there is one through hole 31a in the outer divided punch 31 of the upper punch 21, and the corner portion (tip portion) of the cutting edge 91 which is important for the finished surface accuracy of the throw-away tip 90 is raked. Since the inclined surface 92b to be a surface is formed by the inclined surface 42 of the single outer divided punch 31 of the upper punch 21 as described above, the cutting blade 91 can be given high accuracy.

A fourth embodiment of the present invention will be described with reference to FIGS. In addition, about the structure same as the structure shown by FIGS. 1-11, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
As shown in FIG. 12A, the lower punch 22 includes an outer divided punch 25 and an inner divided punch 26. The inner divided punch 26 includes a first divided punch 126 and a first divided punch. 126 and two second divided punches 127 arranged on both sides of the same.
A through hole 25a is formed in the outer divided punch 25, and the first divided punch 126 is disposed in the through hole 25a so as to sandwich the first divided punch 126 from a direction orthogonal to the punch thickness direction. The second divided punch 127 is inserted.
The second divided punch 127 is fixed to a second inner punch plate 129A disposed below the outer punch plate 27, and the first divided punch 126 is disposed lower than the second inner punch plate 129A. It is fixed to the first inner punch plate 129B.
As shown in FIG. 12B when the lower punch 22 is viewed from above, the outer peripheral edge portion of the press surface 126A of the first divided punch 126 is formed with an edge line portion 126b along the outer peripheral edge portion of the outer divided punch 25 and the outer divided portion. It is comprised from the ridgeline part 126a which does not follow the outer periphery part of the punch 25. FIG.
In addition, the outer peripheral edge portion of the press surface 127A of the second divided punch 127 is adjacent to the ridge line portion 126a of the first divided punch 126, and the ridge line portion 127a not along the outer peripheral edge portion of the outer divided punch 25, and the outer divided punch And 127b along the outer peripheral edge portion.

The area I2 of the press surface 126A of the first divided punch 126 extends to the outer peripheral edge portion of the outer divided punch 25, the ridge line portion 126a of the first divided punch 126, and the outer peripheral edge portion of the outer divided punch 25 of the ridge line portion 126a. It is configured to be 50% or more (preferably 80% or more) of the area O2 (the area of the hatched portion in FIG. 12B) surrounded by the extension line.
Further, the area I3 of the press surface 127A of the second divided punch 127 includes an outer peripheral edge portion of the outer divided punch 25, a ridge line portion 127a of the second divided punch 127, and an outer peripheral edge portion of the outer divided punch 25 of the ridge line portion 127a. It is configured to be 50% or more (preferably 80% or more) of the area O3 (the area of the hatched portion in FIG. 12 (b)) surrounded by the extension line extending in the direction.

    The dividing line 80 formed by the outer divided punch 25 and the inner divided punch 26 is formed along the ridge line portion 126b of the first divided punch 126 and the ridge line portions 127a and 127b of the second divided punch 127. The second dividing line 80a constituted by the first dividing punch 126 and the second dividing punch 127 is along the ridge line portion 127a and the ridge line portion 126a that are the boundary between the first and second divided punches 126 and 127. It is formed.

Furthermore, when viewed from above, the ridge line portion 127a of the second divided punch 127 is configured to coincide with both side edges of the pin 24 formed in a columnar shape. That is, the length between the ridge line portions 127 a and 127 a arranged at both ends in the direction orthogonal to the punch thickness direction of the through hole 25 a is formed so as to coincide with the diameter of the pin 24.
The upper punch 21 has the same configuration as the lower punch 22, and the inner divided punch 32 of the upper punch 21 has a third divided punch 132 and two second divided punches arranged on both sides of the third divided punch. The four-part punch 133 is configured.

According to the press-molding die 20 configured in this way, in the filling process, the upper end surface which is the press surface 127A of the second divided punch 127 is the press surface 25A of the outer divided punch 25 of the lower punch 22. The upper end surface which is the press surface 126A of the first divided punch 126 is positioned further above the upper end surface which is the press surface 127A of the second divided punch 127. In this state, the raw material powder is filled in the cavity A.
In the filling ratio adjusting step, the first divided punch 126 and the second divided punch 127 are displaced downward and drawn into the outer divided punch 25, and the third divided punch 132 and the fourth divided punch 133 are moved downward. By pressing the powder, the raw material powder is also satisfactorily drawn directly under the pin 24, and the filling ratio in the direction perpendicular to the punch separation direction of the raw material powder in the cavity A is adjusted well. .
Since the inner divided punches 26 and 32 of the upper and lower punches 21 and 22 are further constituted by a plurality of divided punches 126, 127, 132 and 133, the difference in the length of the pin 24 in the partial punch attachment / detachment direction It is possible to adjust the filling ratio better in response to the above.
Also in this embodiment, the dividing line 80 formed by the inner divided punches 32 and 26 and the outer divided punches 31 and 25, the first and third divided punches 126 and 132, and the second and fourth divided punches 133 and 127 are also formed. And the second dividing line 80a configured by the dividing line 80a is formed on the inner side of the outer peripheral edge portions of the outer dividing punches 31 and 25. Therefore, as shown in FIGS. The stepped portion 70 formed by 80 and the second dividing line 80 a is formed inside the outer peripheral edge portion of the rake face 53.
Furthermore, since it has the same configuration as that of the first embodiment, it is possible to obtain the same operations and effects as those of the first embodiment. In particular, there are a plurality of inner divided punches 26 and 32 of the upper and lower punches 21 and 22. Even though the divided punches 126, 127, 132, 133 are formed, only one through hole 25a is formed in each of the outer divided punches 25, 31, so that the outer divided punch 25, 31 can be manufactured easily and accurately, and since the through hole 25a is open at the center of the press surface 25A, the green compact manufactured on the vertical blade type throw-away tip 50 is molded. Therefore, it is possible to give high accuracy to the corner portion 57 which is important for forming the finished surface of the work material.

A fifth embodiment of the present invention will be described with reference to FIGS. In addition, about the same structure as the structure shown by FIGS. 1-13, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
As shown in FIG. 14, in the press molding die 20 according to this embodiment, the upper punch 21 includes an outer divided punch 31 and two inner divided punches 170, and the lower punch 22 includes an outer divided punch. It is composed of a punch 25 and two inner divided punches 171 and forms a green compact to be formed on the throw-away tip 50 as shown in FIG.
As shown in FIG. 16 when the outer divided punch 25 constituting the lower punch 22 is viewed from above, two through holes 25a are formed on both end portions of the outer divided punch 25.
The through holes 25a and 25a are formed at positions spaced from the outer peripheral edge of the outer divided punch 25 by 0.1 mm or more (preferably 0.5 mm or more), and the first divided punches 171 and 171 are inserted therein. ing.
The outer peripheral edge portion of the press surface 171A at the upper end surface of the inner divided punch 171 is arranged inside the ridge line segments 171b and 171a2 arranged along the outer peripheral edge portion of the outer divided punch 25 and the upper end surface of the outer divided punch 25. The ridge line portion 171a1 does not extend along the outer peripheral edge of the outer divided punch 25.

Further, the area I5 of the press surface 171A of the inner divided punch 171 includes an outer peripheral edge portion of the outer divided punch 25 and a ridge line portion 171a1 that does not follow the outer peripheral edge portion of the outer divided punch 25 among the ridge line portions constituting the press surface 171A. The area O5 (the area of the hatched portion in FIG. 16) surrounded by the extended line extending toward the outer peripheral edge of the outer divided punch 25 of the ridge line portion 171a1 is 50% or more (preferably 80% or more). Is formed.
Therefore, the dividing line 80 formed between the outer divided punch 25 and the two inner divided punches 171 and 171 is along the outer peripheral edge of the inner divided punch 171 formed by the ridge line portions 171a1, 171a2 and 171b. The outer divided punch 25 is disposed on the inner side of the outer peripheral edge of the press surface 25A.
The upper punch 21 is configured in the same manner as the lower punch 22 and includes an outer divided punch 31 and two inner divided punches 170 and 170.

In the press molding die 20 configured in this manner, in the filling process, the raw material powder is cavified in a state where the press surface 171A of the inner divided punch 171 of the lower punch 22 is positioned below the press surface 25A of the outer divided punch 25. Filled into tee A.
In the filling ratio adjusting step, when the upper punch 21 presses the upper surface side of the raw material powder, the outer divided punch 25 of the lower punch 22 is displaced downward, and at the same time, the outer divided punch 31 of the upper punch 21 is The raw material powder is pressed below the inner divided punch 170.
For this reason, the raw material powder in the cavity A flows directly under the pin 24, the density of the raw material powder filled in the cavity A is adjusted in the direction perpendicular to the punch sliding direction, and the raw material powder filling ratio is good. Can be adjusted.
Moreover, in this embodiment, the dividing line 80 is formed in two places on the both ends of the outer divided punches 25 and 31 inside the outer peripheral edge portions of the press surfaces 25A and 31A of the outer divided punches 25 and 31. Therefore, two step portions 70 formed on the throw-away tip 50 are formed on the inner side from the outer peripheral edge portions on both ends of the rake face 53.
As described above, since the stepped portion 70 is formed on the inner side of the outer peripheral edge portion on both ends of the rake face 53, the first implementation is also performed in this embodiment except that two through holes 25a are formed. The same action and effect as the form can be obtained.

A sixth embodiment according to the present invention will be described with reference to FIGS. 17 and 18. In addition, about the same structure as the structure shown by FIGS. 1-16, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
As shown in FIG. 17 (a), the press-molding die 20 according to the present embodiment has a ball end mill throw similar to that of the third embodiment, as shown in FIGS. 18 (a) and 18 (b). The away chip 90 is formed.

As shown in FIG. 17A, the press mold 20 is provided in the cavity A, the upper and lower punches 21 and 22 that are separated from each other in the vertical direction, the die 23 in which the cavity A is formed, and the cavity A. It consists of pins 24.
As shown in FIGS. 17A and 17B, the upper punch 21 includes an outer divided punch 31 and two inner divided punches 170.
Through holes 31 a and 31 a are formed in the inclined surfaces 42 and 42 of the outer divided punch 31, respectively, and the through hole 31 a is 0.1 mm or more from the outer peripheral edge of the outer divided punch 31 (preferably 0. 5 mm or more.) It is formed at a spaced position.
The inner divided punches 170, 170 are fitted into the through holes 31 a formed in the outer divided punch 31, and the press surface 170 </ b> A on the lower end surface of the inner divided punch 170 goes toward the tip side of the outer divided punch 31. The inclined surface is gradually inclined downward.
As shown in FIG. 17B when the upper punch 21 is viewed from the bottom, the outer peripheral edge portion of the press surface 170A of the inner divided punch 170 is a ridge line portion 170b along the outer peripheral edge portion of the outer divided punch 25, and the outer divided punch. 25, and a ridge line portion 170a not extending along the outer peripheral edge portion.

The area I5 of the press surface 170A of the inner divided punch 170 is an area O5 surrounded by the outer peripheral edge portion of the outer divided punch 25, the ridge line portion 170a of the inner divided punch 170, and the extended line of the ridge line portion 170a (FIG. 17B). ) Is 50% or more (preferably 80% or more) of the area hatched in ().
The lower punch 22 includes an outer divided punch 25 and two inner divided punches 171. The press surface 171A of the inner divided punch 171 and the press surface 25A of the outer divided punch 25 are flat surfaces. .

In the press mold 20 configured as described above, when the upper and lower punches 21 and 22 compress the raw material powder filled in the cavity A in the pressurizing step, the throw-away for the ball end mill shown in FIG. The green compact formed on the chip 90 is formed.
At this time, since the dividing line 80 between the outer divided punch 31 and the inner divided punch 170 is not located at the curved portion 42a of the outer divided punch 31, the portion corresponding to the cutting edge 91 of the throw-away tip 90 is a single part. It is comprised by the outer side division punch 31 made into this structure.
That is, the raw material powder enters the dividing line 80 between the outer divided punch 31 and the inner divided punch 170, or the raw material powder is compressed in a state where the lower end surfaces of the outer divided punch 31 and the inner divided punch 170 do not match. As a result, the stepped portion 70 formed on the throw-away tip 90 is formed inside the outer peripheral edge of the flat plate 92 of the throw-away tip 90.
As described above, the stepped portion 70 is not formed on the cutting edge 91, and can obtain the same operation and effect as in the first embodiment, and the throw-away tip 90 similar to that in the third embodiment. The green compact that becomes can be formed.

A seventh embodiment of the present invention will be described with reference to FIGS. In addition, about the same structure as the structure shown by FIGS. 1-18, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
In the present embodiment, the lower punch 22 includes two inner divided punches 171 provided on both sides of the outer divided punch 25, and the inner divided punch 171 includes the first divided punch 172 and the second divided punch 171. 173.
Through holes 25a and 25a are formed on both ends of the outer divided punch 25, and the first divided punch 172 and the second divided punch 173 are fitted into the through holes 25a.
The first divided punch 172 is disposed on both ends of the outer divided punch 25, and the second divided punch 173 is disposed on the inner side of the first divided punch 172.

When the lower punch 22 is viewed from above, the outer peripheral edge portion of the press surface 172A of the first divided punch 172 is disposed in a direction along the outer peripheral edge portion of the press surface 25A of the outer divided punch 25, as shown in FIG. 172b, 172a2, and a ridge line portion 172a1 which is disposed inside the press surface 25A and does not follow the outer peripheral edge portion of the outer divided punch 25.
Further, the outer peripheral edge portion of the second divided punch 173 has ridge lines 173b and 173b along the outer peripheral edge portion of the press surface 25A of the outer divided punch 25 and a ridge line not along the outer peripheral edge portion of the press surface 25A of the outer divided punch 25. It consists of parts 173a and 173a.

The area I6 of the press surface 172A of the first divided punch 172 is an area surrounded by the outer peripheral edge of the outer divided punch 25, the ridge line part 172a1, and the extended line of the ridge line part 172a1 to the outer peripheral edge part of the outer divided punch 25. It is formed to be 50% or more (preferably 80% or more) of O6 (the area of the hatched portion in FIG. 20).
In the present embodiment, when the ridge line portion 172a1 is viewed from above, it is configured to coincide with both side edges of the pin 24 (not shown).
The area I7 of the press surface 173A of the second divided punch 173 includes an outer peripheral edge portion of the outer divided punch 25, ridge line portions 173a and 173a, and an extension line of the ridge line portions 173a and 173a to the outer peripheral edge portion of the outer divided punch 25. Is formed so as to be 50% or more (preferably 80% or more) of the area O7 surrounded by.
The upper punch 21 is configured similarly to the lower punch 22.

In the press-molding die 20 configured in this way, in the filling step, the press surface 173A of the second split punch 173 of the lower punch 22 is positioned below the press surface 25A of the outer split punch 25, and the first The raw material powder is filled into the cavity A in a state where the press surface 172A of the one-division punch 172 is positioned below the press surface 173A.
In the filling ratio adjustment step, when the press surface 21A of the upper punch 21 presses the upper surface of the raw material powder, the outer divided punch 25 and the second divided punch 173 maintain the positional order of the press surfaces 25A, 173A, 172A. Then, the outer divided punch and the second divided punch of the upper punch 21 press the raw material powder downward so as to interlock with the movement of the lower punch 22.
For this reason, the filling ratio of the raw material powder is adjusted well by allowing the raw material powder to flow well under the pins 24.
In the present embodiment, since the inner divided punch 171 has a plurality of first and second divided punches 172 and 173 as in the fourth embodiment, the same operations and effects as in the fourth embodiment are achieved. Obtainable.

The eighth embodiment of the present invention will be described with reference to FIGS. In addition, about the same structure as the structure shown by FIGS. 1-20, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
As shown in FIG. 21, the lower punch 22 of the press-molding die 20 (not shown) according to the present invention has an outer peripheral edge portion of the press surface 22A composed of ridge lines 195 and 196 when viewed from above. The shape is generally rhombus.
The lower punch 22 is inserted into a central divided punch 191 disposed at the center, an outer divided punch 192 disposed on both sides of the central divided punch 191, and a through hole 25 a formed in the outer divided punch 192. The inner divided punch 171 is formed.
The outer divided punch 192 is formed in a substantially fan shape, and a convex curved surface portion that is gradually curved upward is formed from the inside of the press surface 22A toward the tip portion side, and as it is directed to the tip portion side. The flat portion 193 is formed at the tip of the tip portion.
Further, the outer peripheral edge of the outer divided punch 192 is a ridge line part 193a that forms the outer peripheral edge part of the flat part 193, and the vicinity of the substantially central part of the ridge line parts 195 and 196 of the press surface 22A connected to the ridge line part 193a. The ridge line portions 195a and 196a extending to the rim, and the ridge line portions 196a and 196a that are connected and curved are formed.
The through hole 25 a formed in the outer divided punch 192 is formed inside the outer peripheral edge of the outer divided punch 192.

The press surface 191A of the central split punch 191 is a flat surface, and the outer peripheral ridge line portion of the press surface 191A of the central split punch 191 is a portion where the ridge line portion 195 and the ridge line portion 196 of the press surface 22A intersect at an obtuse angle. The ridge line portion 197a to be formed and the ridge line portion 197b formed along the ridge line portion 196b of the outer divided punch 192 are configured.
In the lower punch 22 configured in this way, a dividing line 80 formed by the outer divided punch 192 and the inner divided punch 171 is formed along the outer peripheral edge portion of the press surface 171A of the inner divided punch 171.
Further, a dividing line 80b formed by the outer divided punch 192 and the central divided punch 191 is formed along the ridge line portions 196b and 197b.
Therefore, both end portions of the dividing line 80b extend to the ridge line portions 195 and 196 of the press surface 22A. Note that the upper punch 21 has a vertically inverted shape and has the same configuration as the lower punch 22.

According to the press-molding die 20 (not shown) configured as described above, when the upper and lower punches 21 and 22 compress the raw material powder in the cavity A, they are formed into a throw-away tip 180 as shown in FIG. A green compact is formed.
At this time, the slow way chip 180 is formed so as to have a substantially rhombus shape when viewed from above, and includes a top plate surface 181 and a peripheral surface 182 formed around the top plate surface 181. ing.
A central portion of the top plate surface 181 is a flat portion 183, and on both sides of the flat portion 183, breakers 184 that gradually go inward toward the tip main body toward the tip end side are formed. On the side, a flat portion 185 is formed. A cutting edge 185 a is formed on the outer peripheral edge of the flat portion 185.

That is, in the compression process, when the lower punch 22 compresses the raw material powder, the press surface 191A forms a portion corresponding to the flat portion 183, and the convex curved surface portion of the outer divided punch 192 forms a portion corresponding to the breaker 184. Furthermore, the ridge line part 193a of the flat part 193 forms a part corresponding to the cutting edge 185a.
At this time, since the dividing line 80 is formed inside the outer peripheral edge of the outer dividing punch 192, the stepped portion 70 formed in the throw-away tip 180 by the dividing line 80 is inside the outer peripheral edge of the chip body. Formed.
Further, since the dividing line 80b is formed along the ridge line part 197b of the central dividing punch 191, the stepped part 70b formed on the throw-away tip 180 by the dividing line 80b is formed between the breaker 184 and the flat part 183. It is formed along the intersecting ridge line part.
As described above, the stepped portion 70b is formed on the top surface 181 inside of the breaker 184, while the cutting edge 185a is formed on the tip end side of the breaker 184, so that the stepped portion 70b reaches the cutting edge 185a. It is prevented from stretching.
That is, according to this press molding die 20, at least a portion corresponding to the cutting edge 185a is formed by one outer divided punch 192, so that the cutting edge 185a can be accurately molded, It is possible to prevent the stepped portions 70 and 70b from being formed on the blade 185a.
As described above, according to the present embodiment, since the stepped portions 70 and 70b are prevented from being formed on the cutting edge 185a, it is possible to obtain the same operation and effect as in the first embodiment, In the present embodiment, since the inner divided punch 171 is provided at both ends of the press surface 22A, the same actions and effects as in the fifth embodiment can be obtained.

In FIG. 21, the through hole 25a into which the inner divided punch 171 is inserted is formed in the flat portion 193 of the outer divided punch 192. Instead, as shown in FIG. 25a may be formed on the convex curved surface portion of the outer divided punch 192, and the inner divided punch 171 may be fitted into the through hole 25a. However, the through hole 25a in FIG. 23 (a) is formed by the central divided punch 191 and the outer divided punch 192, that is, one divided punch for forming a portion continuous with the cutting edge portion 185a of the lower punch 22. Is further constituted by a plurality of divided punches (a central divided punch 191 and an outer divided punch 192), and a through hole 25a is formed between the divided punches 191 and 192.
Further, even if the through hole 25a is formed in the convex curved surface portion of the outer divided punch 192 in this way, the through hole 25a is not formed between the central divided punch 191 as shown in FIG. As shown in (b), the through hole 25a is formed inside the press surface 192A of the outer divided punch 192 from the ridge line portion 196b of the outer divided punch 192, and the inner divided punch 171 is inserted into the through hole 25a. Good.
In the case where the lower punch 22 is configured as shown in FIGS. 23A and 23B, the stepped portions 80 and 80b are formed at positions separated from the corner portion of the cutting edge 185a, particularly at the time of cutting. The influence by the step portions 80 and 80b can be reliably suppressed. Further, when the upper and lower punches 21 and 22 are configured as described above, the through hole 25a is not formed in the flat portion 193 of the outer divided punch 192, and the cutting edge 185a including the corner portion is formed in the throw-away tip 180. Since the periphery of the portion is press-formed by the flat portion 193 of the single outer divided punch 192, higher accuracy can be obtained.

In the first to eighth embodiments, some of the outer peripheral edge portions of the press surfaces 26A, 32A, 170A, and 171A such as the inner divided punches 26, 32, 170, and 171 are formed on the outer divided punches 25 and 31. Or are formed at equal intervals so as to extend in parallel along the outer peripheral edge portions of the press surfaces 25A, 31A, 192A of the split punch 192. For example, as shown in FIG. The outer peripheral edge (ridge line portions 171a2, 171b) of the press surface 171A of the punch 171 and the inner periphery of the through hole 25a into which the inner punch 171 is inserted are wavy with respect to the outer peripheral edge of the press surface 25A of the outer divided punch 25. Or may be formed so that the distance between them is gradually changed. Incidentally, as shown in FIG. 24, when the outer peripheral edge of the press surface 171A of the inner divided punch 171 is formed in a corrugated shape, the press surface 171A slightly protrudes or retracts from the press surface 25A of the outer divided punch 25. By forming the green compact in this manner, a concave or convex chip breaker whose outer peripheral edge is bent into a corrugated shape is formed on the rake face 53 of the throw-away tip 50, thereby improving the chip breaking effect. be able to.
Further, in the first to eighth embodiments, the case where the green compact is formed by the punches that are separated from each other in the up and down direction has been described. However, when the green compact is formed by separating and contacting a plurality of punches in the horizontal direction. The present invention can also be applied to the case where the vertical direction and the horizontal direction are separated from each other. Furthermore, for example, when a plurality of punches are separated from each other in the horizontal direction, three punches are separated from three directions, four punches are separated from four directions, or more punches are used. In this case, for example, when the three punches are separated from the three directions, the separation directions of these punches are directed radially from the cavity in a top view, so that the punches are straightened. You may be the structure which does not oppose on a line.

  According to the manufacturing method of the cutting blade member of the cutting tool and the press molding die of the green compact used in the manufacturing method according to the present invention, the stepped portion formed on the rake face of the cutting blade member extends to the cutting blade. By preventing this, it is possible to prevent the formation of a stepped portion on the cutting edge, thereby improving the surface roughness of the work material and the tool life of the cutting edge member, Industrial applicability is recognized because chips can be discharged well.

20 Press molding die of green compact 21 Upper punch 22 Lower punch 23 Die 25, 31 Outside split punch (one split punch)
26, 32, 170, 171 Inside split punch (other split punches)
126 1st divided punch 127 2nd divided punch 132 3rd divided punch 133 4th divided punch 172 1st divided punch 173 2nd divided punch

Claims (12)

Press forming comprising a plurality of 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 therebetween. In a manufacturing method of a cutting tool member of a cutting tool, which press-molds a green compact manufactured on a cutting tool member of a cutting tool by compressing the raw material powder put into the cavity with the punch using a mold. ,
At least one of the plurality of punches is constituted by a plurality of divided punches having a divided surface extending in a direction of separating the punch when the raw material powder is compressed, and the cutting blade member A method for manufacturing a cutting blade member of a cutting tool, wherein at least a portion corresponding to one continuous cutting blade portion is formed by one of the divided punches. In the manufacturing method of the cutting-blade member of the cutting tool described in Claim 1,
The other divided punch is disposed inside the one divided punch, and all the portions corresponding to the continuous outer peripheral ridge line of the green compact including the cutting edge portion are formed by the one divided punch. A method for manufacturing a cutting blade member of a cutting tool. In the manufacturing method of the cutting-blade member of the cutting tool described in Claim 1 or 2,
The green compact has a flat plate shape, and at least one of the peripheral surfaces arranged around the flat plate surface is compressed by a punch constituted by the plurality of divided punches. Manufacturing method of the cutting blade member. In the manufacturing method of the cutting-blade member of the cutting-blade tool described in Claim 3,
A method for producing a cutting blade member of a cutting tool, wherein a hole is formed in the flat plate surface of the green compact by means of a pin that can be projected and retracted in a direction perpendicular to the direction of separation of the punch in the cavity. . 5. A green compact press-molding die used in the method for producing a cutting blade member of a cutting tool according to claim 1, wherein the punches 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,
At least one of the plurality of punches is provided so as to be slidable by being inserted into one divided punch that slides along a peripheral surface in the cavity and a through-hole formed in the one divided punch. A green compact press molding die comprising a plurality of split punches with other split punches. In the green compact press-molding die according to claim 5,
The green compact press-molding die, wherein the other split punch is further constituted by a plurality of split punches. In the green compact press molding die according to claim 5 or 6,
The area of the press surface of the other divided punch is along the outer peripheral portion of the line segment that forms the contour of the press surface of the one divided punch and the press surface of the other divided punch. The green compact press-molding die is 50% or more of an area surrounded by a line segment that does not extend and an extension line to the outer peripheral edge. In the green compact press mold according to claim 7,
The area of the press surface of the other divided punch is along the outer peripheral portion of the line segment that forms the contour of the press surface of the one divided punch and the press surface of the other divided punch. The green compact press-molding die is 80% or more of an area surrounded by a line segment that does not extend and an extension line to the outer peripheral edge. In the green compact press-molding die according to any one of claims 5 to 8,
2. A green compact press-molding die, wherein the through hole formed in the one divided punch is formed at a position spaced 0.1 mm or more from the outer peripheral edge of the one divided punch. In the green compact press mold according to claim 9,
The green compact press-molding die, wherein the through hole is formed at a position spaced 0.5 mm or more from the outer peripheral edge of the one divided punch. In the green compact press-molding die according to any one of claims 5 to 10,
A green compact press-molding die, wherein a through-hole into which the other divided punch is inserted is formed at one location in the one divided punch. In the green compact press-molding die according to any one of claims 5 to 11,
On the press surface of the punch constituted by the plurality of divided punches, there are formed concavo-convex portions that are relatively concave or convex with respect to adjacent portions in the direction of separation of the punch, and the plurality of divided punches The dividing line is formed along a boundary portion between the uneven portion and the adjacent portion.

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