JPH11156606A - Throw away tip, manufacture thereof, and tool unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a throw away tip, easily manufactured by die press without after working, etc., while a projection, becoming a tip breaker in accordance with a rake face, is formed. SOLUTION: A throw away tip 1 has a plane-like rake face 302 ranging with a cutting blade 301, while, a recess 1c is formed, so as to range with the rake face 302, on a side opposite to the cutting blade 301 to the rake face 302. A projection 1b, having a width narrower than that of the recess 1c, is formed so as to be protruded from the inner surface of the recess 1c, in a state where the whole or part is positioned within the recess 1c. The throw away tip 1 can be extremely easily manufactured by forming a die press in a thickness direction through forming the projection 1b within the recess 1c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throw-away insert, and more particularly to a throw-away insert used for a cutting edge such as grooving, threading or parting off.

[0002]

2. Description of the Related Art When a workpiece is grooved, threaded or cut off by turning using a throw-away insert, treatment of chips generated at the time of cutting often poses a problem. For example, if chips are continuously discharged in a long whisker-like form in processing such as thread cutting, the cuttings may become entangled with a work material or a cutting tool and smooth processing may not be performed. Therefore, Japanese Patent Application Laid-Open
Japanese Patent No. 24608 discloses a throw-away chip in which a protruding chip breaker is formed on a rake face. According to this, when the chip generated at the cutting edge gets over the chip breaker, it is curled and divided into small pieces, so that efficient cutting can be performed.

As a method of manufacturing such a throw-away chip with a chip breaker, the above-mentioned publication discloses a method of manufacturing a molded body by injection molding.

[0004]

As the material of the above-mentioned indexable insert, a sintered composite material containing a considerable amount of a metal component such as a cemented carbide or a cermet is generally used.
Therefore, when it is manufactured by the injection molding method, the following problems are inevitable. In the injection molding method, it is necessary to mix as much as 30 to 40% by volume of wax with respect to the raw material powder. Therefore, the reaction between the metal component and the wax component (for example, carbon) in the material is unavoidable, and is likely to cause deformation during sintering and performance degradation of the obtained chip. Since the molded body after dewaxing has a much larger shrinkage amount during sintering than a general die-press molded body, dimensional variations of the sintered body are likely to occur. Because of the large amount of the wax compounded, the dewaxing step before firing takes a long time and is inefficient.

[0005] In this case, the above-mentioned problem can be avoided by adopting a method in which a raw material powder is die-pressed to form a molded body and the molded body is fired.
Japanese Patent Application Laid-Open No. 608-608 states that when manufactured by die press molding, a chip having no chip breaker is used in a fired state, and the chip breaker and the rake face need to be post-processed by electric discharge machining or the like. . To give a supplementary explanation, the indexable insert disclosed in the above-mentioned publication is a substantially triangular plate-shaped one using three ridges in the thickness direction as cutting edges, and is manufactured by die press molding. In this case, it is necessary to set the pressing direction to the chip thickness direction.
Since the rake face is formed on the peripheral face in the case of the chip, the chip breaker projects from the rake face in a direction perpendicular to the pressing direction.

Therefore, in the above-mentioned publication, it is judged that it is extremely difficult to form a chip breaker at the stage of a press molding step, and injection molding is employed. That is, as shown in FIG. 26, when the above-described chip breaker is formed at the time of pressing, the press punches 201, 20
In the peripheral edge of 2, thin protrusions 201a and 202a must be provided at positions corresponding to the chip breaker portion B. However, the protrusions 201a and 202a are thin, but tend to have insufficient mechanical strength. In addition, the chip breaker portion B has a high powder compression ratio and a high pressure is applied. They are easy to use and hardly endure long-term use.

In this case, if pressing is performed in a direction perpendicular to the thickness direction of the chip, a part of the side surface can be formed by the punch surface, so that the chip breaker can be formed relatively easily. However, in this method, the shape that can be formed is limited to a substantially square shape, and it is almost hopeless to manufacture the above-described triangular plate-like shape. Also,
Since the chip thickness is fixed by the size of the die hole, it is uneconomical to manufacture chips of various thicknesses by preparing a large number of expensive die and punch sets.

An object of the present invention is to provide a throw-away chip and a method of manufacturing the same which can be easily manufactured by a die press while post-processing or the like is unnecessary or simplified while a convex portion serving as a chip breaker is formed corresponding to a rake face. Another object of the present invention is to provide a tool unit using the indexable insert.

[0009]

The structure of the throw-away tip according to the present invention is as follows. (Claim 1) A pair of a rake face and a flank formed adjacent to each other in the circumferential direction is formed on the outer peripheral surface thereof as a whole in a substantially plate shape, or a plurality of pairs are formed along the circumferential direction. A chip body having a cutting edge in the thickness direction formed at each intersection of the rake face and the flank forming a pair, and the outer peripheral surface of the chip body is provided on the side opposite to the cutting edge with respect to the rake face. A concave portion is formed so as to be continuous with the concave portion, and the concave portion has a shape that is open on at least one end surface in the thickness direction of the chip body (hereinafter, the end surface in the thickness direction is referred to as a main surface), and is entirely formed in the concave portion. Or, in a form in which a part is located, a convex portion is formed so as to protrude from the bottom surface of the concave portion,
Further, when considering a powder compact having a shape corresponding to the chip body, the outer peripheral surface of the chip body and thus the outer peripheral surface of the powder compact are so formed that the powder compact is obtained by die pressing in the thickness direction. However, by sliding relative to the inner surface of the die hole of the press die in one of the directions corresponding to the pressing direction, the press die has a shape that can be released from the die hole.

(Claim 2) In claim 1, in the protruding direction of the projection, the top of the projection is formed so as to protrude from an edge position on the side of the rake face that is continuous with the recess.

(Claim 3) In claim 2, the rake face is formed with a flat rake face side cutting edge forming area connected to the cutting edge, and the rake face side cutting edge forming area is extended to the concave side. Occasionally, the top of the projection protrudes beyond its extension.

(Claim 4) In any one of claims 1 to 3, wherein both end surfaces in the thickness direction of the chip body are main surfaces, and at least one of the main surfaces corresponds to the cutting edge of the main surface. Area including edge (Principal surface cutting edge formation area)
However, the thickness of the main surface is increased so as to protrude from a region adjacent to the main surface.

(Claim 5) In any one of claims 1 to 4, the rake face is formed with a flat rake face side cutting edge forming area connected to the cutting edge, and the concave portion is formed with the rake face side cutting edge forming. The depth when viewed with reference to the extension surface of the area is 0.3 to
It is adjusted in the range of 2.0 mm.

A method for manufacturing a throw-away tip according to the present invention is as follows. (Claim 6) In the method for producing a throw-away chip according to any one of claims 1 to 5, wherein the powder molded body formed by press molding is fired, the press molding machine used for press molding is a die of a press die. Inside the hole,
A cavity is formed by the punch surfaces of the press punches inserted into the die hole from above and below, and the upper and lower press punches are brought closer to each other to press-form the raw material powder filled in the cavities. ,
This is a die press apparatus for producing a powder compact to be a throw-away chip, and the powder in the cavity is compressed in the thickness direction of the powder compact to be formed by upper and lower press punches.

(Claim 7) According to claim 6, by changing the filling amount of the raw material powder into the cavity, a throw-away chip having substantially the same outer shape in plan view and different thicknesses is manufactured. I did it.

(Claim 8) In claim 6 or 7,
The powder compact has two or more portions having different thicknesses. At least one of the upper press punch and the lower press punch is divided into a plurality of portions corresponding to the portions having different thicknesses. The punches compressed the powder in the cavity with different strokes depending on the thickness of each corresponding part of the powder compact to be obtained.

Furthermore, the configuration of the tool unit described in the claims of the present invention is as follows. (Claim 9) It is characterized by comprising the throw-away tip according to any one of claims 1 to 5, and a tip holder formed in a rod shape and having a tip portion to which the throw-away tip is detachably attached. Tool unit.

(Claim 10) In claim 9, a flat reference surface extending in the longitudinal direction of the chip holder is formed on the outer surface of the chip holder, and the cutting edge of the indexable insert is set as a reference. Being substantially parallel to the surface, and along the longitudinal direction of the reference surface, the cutting blade, the rake surface and the concave portion are detachably attached to the chip holder so as to be arranged in this order from the distal end side. Also, in a state where the throw-away tip is attached to the tip holder, the reference plane is substantially horizontal, and when the tip holder is held in a posture in which the projection direction of the protrusion is upward, in a direction orthogonal to the reference plane. The height of the protrusion of the throw-away tip is adjusted so as to protrude from the cutting edge position and not to protrude from the rear upper edge position of the recess.

[0019]

In the structure of the indexable insert according to the first aspect of the present invention, a concave portion is formed on the side opposite to the cutting edge with respect to the rake face so as to be continuous therewith.
The convex portion was formed so as to protrude from the bottom surface of the concave portion so as to be entirely or partially located in the concave portion. This projection acts as a chip breaker for chips generated during cutting, and the chips generated by the cutting blade project at the center in the width direction corresponding to the projection when going over the projection. To be deformed. Then, the chips are likely to curl when climbing over the convex portion or when they extend further and hit the inner surface on the rear side of the concave portion. Cutting can be performed. By forming the convex portion in the concave portion, the indexable insert can be extremely easily manufactured by die pressing in the thickness direction.

This will be described with reference to a schematic diagram. As shown in FIG. 1A, since the convex portion 1b is formed so as to protrude from the bottom surface of the concave portion 1c, when the concave portion 1c is not formed, The height can be increased as compared with. And
The concave portion 1c has two main surfaces 1d, 1 of the chip body 1a.
e, it has a shape open to at least one of them (both in the figure). Therefore, as shown in FIG. 1 (b), when producing the powder compact PC by die pressing in the thickness direction, The corresponding portion B is a protruding portion 101a protruding from the outer edge of the front end surface of the press punch 101 (or 102).
(Or 102a). In this case, the protruding portion 101a (or 10
2a) can be made thicker and the press area for the corresponding portion B can be increased, so that the protruding portion 101a (or 1
02a) is unlikely to occur.

In order to enable such press forming in the thickness direction, in the present invention, the outer peripheral surface of the chip body and, consequently, the outer peripheral surface of the powder molded body correspond to the inner surface of the die hole of the press die in the pressing direction. The shape is such that it can be released from the die hole by relatively sliding in either direction. Such an outer peripheral surface shape more specifically satisfies the following conditions. Hereinafter, FIG.
The chip body 1a is parallel to the thickness direction at an arbitrary cross section S parallel to the thickness direction through a midpoint M of the maximum width Wmax of the cross section in a direction orthogonal to the thickness direction. When the reference line O is virtually set, the shape of the cross-sectional outline (P1 to P3) representing the outer peripheral surface of the chip 1 needs to be one of the following.

The sectional outline portion is substantially parallel to the reference line O: the outline portion P1 in FIG. With reference to the drawing, the powder molded body PC has such a shape of the cross-sectional outline, so that, for example, the upper punch 101 is retracted and the lower punch 102
Is relatively raised with respect to the die 100, and this can be released from the die hole 100a.

In the sectional outline portion, the distance L from the reference line O monotonically decreases from one side of the reference line O to the other side: The outline portion P2 shown in FIG. Corresponds to. This is a case where a die taper is provided in the die hole 100a. In this case, if the powder compact PC is slid relative to the die 100 in a direction in which the above L increases, the powder compact PC can be released.

In the cross-sectional outline, there is a maximum point U at the center where the distance L from the reference line O is maximum, and the maximum point U
The distance L from the reference line O monotonically decreases as both side parts Pa and Pb move away from the maximum point U: FIG.
The outline part P3 in (a) corresponds to this. Even when a protrusion (for example, the above-described protrusion 1b) is formed in a direction perpendicular to the pressing direction from the outer peripheral surface of the powder compact PC, if the protrusion does not have two or more local maximums, the die is formed. Hole 1
00a and the tip of the punch 101 (or 102).
1 can be released from the die hole 100a without any problem. In the example shown in the figure, the maximum point U appears on the top surface of the flat portion 1b, the top surfaces of both side portions Pa and Pb are formed by the inner surface of the die hole 100a, and the remaining portions are formed by the punch 1.
01, 102 formed by the protruding portions 101a, 102a. Similarly, by retracting the upper punch 101 and raising the lower punch 102 relatively to the die 100, the powder compact PC can be released from the die hole 100a.

Next, according to the structure of the throw-away tip of the second aspect, in the projecting direction of the projection, the top of the projection is formed so as to project beyond the edge position on the side continuous to the recess on the rake face. Thus, when chips generated by the cutting blade are discharged along the rake face, the chips can be reliably pressed against the convex portion, and the effect of chip separation can be further improved.
In addition, the portion of the protrusion projecting from the extension surface is narrower than the width of the recess in the thickness direction of the chip body, thereby promoting the deformation of the chips pressed against the protrusion. This is desirable in order to enhance the effect of curling the chips and eventually the effect of dividing the chips. For example, when a flat rake face-side cutting edge forming area connected to the cutting edge is formed on the rake face, when the rake face-side cutting edge forming area is extended to the concave side, the top of the convex part is moved to the concave side. By protruding from the extension surface, the above effect is remarkably achieved (claim 3).

In the structure of the throw-away insert according to the present invention, both ends in the thickness direction of the chip main body are used as main surfaces, and at least one of the main surfaces includes a region including the cutting edge of the main surface (the main surface side cutting edge). The formation region) is made thicker on the main surface so as to protrude from a region adjacent thereto. That is, since a protruding portion is provided on the tip end side of the cutting edge portion to increase the thickness toward one or both main surfaces, the surface of the protruding portion is ground to reduce the thickness of the cutting edge portion. Can be adjusted. Further, in a conventional indexable insert having no such a raised portion, the entire surface of the cutting edge portion of the main surface must be ground, but in this configuration, the raised portion is provided on a part of the cutting edge portion. Since there is only one part, the number of parts to be ground is small, the processing is easy, and the cost can be reduced.

The configuration of the indexable insert according to the fifth aspect is a more desirable mode when the rake face side cutting edge forming region is formed. That is, the depth of the above-described concave portion when viewed on the basis of the extension surface of the rake face side cutting edge formation region is adjusted in the range of 0.3 to 2.0 mm. By setting the depth of the concave portion in this range, the effect of preventing the press punch from being broken as described above with reference to FIG. 1 is further enhanced, and the manufacturing thereof is further facilitated. If the depth of the concave portion is less than 0.3 mm, the pressing area of the convex portion on the chip main surface side may be insufficient, and the formation of the convex portion may not be performed properly. On the other hand, if the depth of the recess exceeds 2 mm, the recess becomes too large relative to the chip body, taking into account the general dimensions of this type of throw-away tip, and thus corresponds to the bottom edge of the recess. At the position, the thickness of the chip main body in the direction along the main surface is insufficient, which may cause a problem that the mechanical strength of the portion is insufficient. The depth of the concave portion is more desirably 0.3 to
It is better to adjust within a range of 1 mm.

Next, the indexable insert of the present invention is detachably attached to the tip of a rod-shaped tip holder, and is used for machining such as cutting in the form of a tool unit. 9).

According to the tenth aspect of the present invention, a flat reference surface extending along the longitudinal direction of the tip holder is formed on the outer surface of the tip holder. This reference plane can be used to give a cutting direction by the throw-away tip (a feed direction of the throw-away tip with respect to the workpiece). The indexable insert is positioned on the tip holder such that the cutting edge is substantially parallel to the reference plane, and along the longitudinal direction of the reference plane, the cutting edge, the rake face, and the recess are arranged in this order from the distal end side. It will be detachably attached. Then, assuming this mounting mode, when the tip holder is held in a posture in which the reference surface is substantially horizontal and the projecting direction of the projecting portion is upward, the projecting portion of the throw-away tip is made to protrude from the cutting edge position. This is desirable in order to enhance the deformation effect of the chips generated by the cutting blade. On the other hand, it is desirable that the convex portion does not protrude beyond the rear upper edge position of the concave portion in order to enhance the effect of dividing the chips deformed in the convex portion by hitting the rear inner surface of the concave portion.

The above-described indexable insert according to the present invention is, as described in claim 6, formed into a powder compact by press molding uniaxially in the thickness direction using a die press machine. It can be manufactured very easily by firing. In addition, as long as the shape is a plate shape, the planar shape is not limited to a square shape, and there is an advantage that a triangular shape, a parallelogram shape, a rhombus shape, or the like can be freely selected. Then, in comparison with the prior art using the injection molding method described in the above-mentioned publication, it can be said that the following effects are also achieved.

The amount of additives such as a lubricant and a binder to be blended in the raw material powder may be small. For example, when a cemented carbide or cermet is used as a material, the reaction between the metal component in the material and the additive may be reduced. Since it is unlikely to occur, a high performance indexable insert with few sintering defects can be obtained. The die press molded product has a smaller shrinkage amount during sintering than the injection molded product. Therefore, dimensional variation of the sintered body is less likely to occur and a near-net shape is easily obtained, so that the amount of finishing after sintering can be reduced. Since the amount of the additive is small, the degassing step (or the debinding step) before sintering can be shortened, and the production efficiency is high.

Further, since pressing in the thickness direction is possible, the outer shape in plan view is substantially the same by changing the filling amount of the raw material powder into the cavity as described in claim 7. Also, there is an advantage that indexable inserts having different thicknesses can be manufactured with the same set of die and punch. This eliminates the need to prepare a large number of expensive die and punch sets when manufacturing chips of various thicknesses, which is very economical.

For example, in the case of a throw-away insert having a shape as shown in FIG. 24 (a), as shown in FIG. 24 (b), the thickness of the cutting edge corresponding to the groove width or the like is equal to the reference thickness of the insert (most thickness). (Thickness of the thick part: formed at the center of the chip, for example), the thickness is reduced by a step on one main surface side, or as shown in FIG. (For example, a throw-away tip of claim 3). In this case, when the powder compact is manufactured using a die press machine, FIG.
As shown in FIG. 5, when the thick part and the thin part are formed at once by a pair of upper and lower press punches, the powder filling depth is different between the thick part and the thin part. Instead, the compression is performed by the same press stroke, so that a difference occurs in the compression ratio of both portions. Therefore, the apparent density of the obtained powder compact becomes non-uniform, for example, low density in a thick portion and high density in a thin portion. When such a molded body is fired, the shrinkage of the high-density portion is small, and the shrinkage of the low-density portion is large, so that the obtained throw-away chip is likely to be strained, warped, or cracked. If the step is large, manufacturing itself may not be possible. In the case of chips having different levels of steps, different dies must be used.

To solve this, the method of claim 8 is effective. That is, in the method, at least one of the upper press punch and the lower press punch is divided into a plurality of parts, for example, into a split mold corresponding to the portions having different thicknesses, and the powder in the cavity is divided by the divided punches. Compressing with different strokes depending on the thickness of the corresponding parts of the powder compact to be obtained. More specifically, the thick part having a large powder filling depth and the thin part having a small filling depth are separately pressed by a separate press punch, and the former is pressed with a large compression stroke so that the density is not insufficient. Press with a small compression stroke so that the density is not too high. Thereby, even when a thick part and a thin part are formed on the molded body, the density of the molded body can be made substantially uniform, and in the case of a throw-away tip having a large unevenness such as a step on the main surface side. However, simply pressing the density of the powder compact and then sintering it,
A throw-away tip having a good shape can be obtained. Needless to say, it is desirable to provide a difference in the amount of powder to be compressed between the thin portion and the thick portion in order to obtain a compact having a uniform density. In this case, in the die hole, for example, among the divided lower press punches, the one that is responsible for pressing the thick part is located below the one that is also responsible for pressing the thin part, so that the powder in the die hole is It is effective to make the filling depth larger in the former than in the latter.

[0035]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below with reference to some embodiments shown in the drawings. (Embodiment 1) FIG. 3 shows a throw-away chip 1 according to an embodiment of the present invention. The chip 1 is used, for example, for grooving, and has a chip main body 1a formed in a substantially triangular plate shape as a whole. On the outer peripheral surface of the chip main body 1a, a total of three pairs of a rake face 302 and a flank 303 formed adjacently in the circumferential direction are formed corresponding to each vertex position of the triangle. The cutting edge 301 in the thickness direction is formed at the intersection of the rake face 302 and the flank face 303 forming the same.

Each rake face 302 is formed as a planar area (a rake face side cutting edge forming area) connected to the cutting edge 301, and as shown in an enlarged view in FIG. A concave portion 1c is formed so as to be continuous with the rake face 302 in FIG. The concave portion 1c has a shape that is open to an end surface in the thickness direction of the chip body 1a, that is, one or both of the main surfaces. As shown in FIG. 4, a convex portion 1b narrower than the concave portion 1c is formed in the concave portion 1c so as to protrude from the bottom surface 1f of the concave portion 1c.

When the above chip 1 is used, FIG.
As shown in FIG. 1A, the chip 1 is attached to a steel chip holder (hereinafter, simply referred to as a holder) 11 (the chip 1 is thereby attached).
Constitutes an embodiment of the tool unit of the present invention together with the tip holder 11). That is, the chip 1 is fitted into the substantially triangular concave mounting portion 12 provided at the tip of the holder 11 so as to support the outer peripheral surface of the chip 1. Then, the chip 1 is fixed to the holder 11 by sandwiching the side support surface 1 q of the chip 1 on the upper surface side with the locking member 15 and fixing the locking member 15 with the screw 13.

When the chip 1 is mounted on the holder 11, the chip 1 is not deviated from the holder 11. That is, a taper is formed on the side support surface 1q of the chip 1 so that the outer diameter of the chip 1 increases toward the main surface side facing the holder 11 over the entire circumference, while the mounting portion 12 is formed on the outer side thereof. Since the taper whose diameter becomes narrower is formed, when the chip 1 is fitted into the mounting portion 12 and pressed down from above, the chip 1 is pressed to the main A surface side, thereby preventing falling off.

Then, with this chip 1 fixed,
For example, as shown in FIG.
When grooving is performed on 6, the chip 1 is pressed together with the holder 11 in the direction of arrow A to perform cutting. In the present embodiment, the holder 11 is formed, for example, in the shape of a rectangular bar having a rectangular cross section, and the surface opposite to the side support surface 1q in the mounted state of the chip 1 is a flat reference surface. The surface 11a is formed in its own longitudinal direction. The reference surface 11a gives a cutting direction by the chip 1 (feeding direction of the chip with respect to the workpiece: the direction of the arrow in FIG. 5). As shown in FIG. 6, the chip 1 has one cutting edge 301 substantially parallel to the reference surface 11a, and along the longitudinal direction of the reference surface 11a, the cutting edge 301, the corresponding rake surface 302, and the concave portion. 1c are attached to the holder 11 so as to be arranged in this order from the front end side. The tip 1 may be attached to the holder 11 so that the side support surface 1q is substantially parallel to the reference surface 11a as shown in FIGS. 6A and 6C, or FIG. ) And (d),
The side support surface 1q may be attached so as to be inclined forward with respect to the reference surface 11a.

At the time of cutting, as shown in FIGS. 4 (a) and 4 (b), the convex portion 1b acts as a chip breaker for chips D generated during cutting. That is, as shown in FIG. 4B, the band-shaped chip D tries to ride on the top surface of the projection 1b at the center in the width direction, but both edges are outside the projection 1b. So I try to go straight. As a result, as shown in FIG. 4D, the chip D further extends while being deformed so that the center in the width direction rises as shown in the XX section, and the recess 1c.
Tries to curl by hitting the rear inner surface of the.

Then, as in the case of using a conventional chip having no convex portion 1b, when the cross section is not deformed as shown in FIG. The chip D has a coiled shape or an irregular linear shape such as steel wool, and has a large radius and a weak waist. As a result, there is a problem that the discharge direction of the chips D becomes uneasy, and the chips D are apt to stray, and are easily entangled with the work material or the cutting tool (chip). However, by deforming the cross section by the convex portion 1b as described above, the chip D is converted into a material having a strong "hip" and low flexibility. Accordingly, the chips D are finely divided by, for example, bending stress at the time of curling. Since the material is stabilized, the material is hardly entangled with the work material and the cutting tool, and efficient cutting can be performed.

As shown in FIGS. 6 (a) and 6 (b), the tip holder 1 is placed in such a manner that the reference surface 11a is substantially horizontal and the projecting portion 1b of the chip 1 projects upward.
As shown in FIGS. 3C and 3D, when the first protrusion 1 is held, it is possible to make the convex portion 1b protrude beyond the position of the cutting edge 301, thereby reducing the effect of the chip generated by the cutting edge 301. It is desirable in raising. In this case, as shown in FIG. 6D, when the chip 1 is projected on a plane parallel to the main surface, the cutting edge 301 is projected.
The distance H1 in the direction perpendicular to the reference surface 11a from the cutting edge 301 to the contact M is 0.5 mm, where M is a contact point between the tangent line N drawn toward the outline of the projection 1b and the outline. It is desirable to make the following. H1 is 0.5
If it exceeds mm, the resistance when the chips run on the convex portion 1b becomes too large, and the smooth discharge of the chips D may be hindered.

On the other hand, the projecting portion 1b does not protrude beyond the rear upper end edge position 1s of the concave portion 1c, so that chips deformed in the projecting portion 1b are broken by hitting the rear inner surface of the concave portion 1c. Desirable for enhancing the effect. in this case,
The reference plane 11 from the cutting edge 301 to the upper end edge position 1 s
When the distance H2 in the direction orthogonal to a is 2.0 mm or less, the discharge of the chips becomes smoother,
It is more desirable in that the size of the chip (or bite) is not unnecessarily increased. For example, when the chip 1 is used for deep grooving or the like, the above H2 is 2.0 m
When the value is larger than m, smooth discharge of chips may be hindered.

Referring back to FIG. 3, a screw insertion hole 4 is formed in the center of the main surface in the thickness direction so that the chip 1 can be attached by screwing. A main surface 1p of the main surface is flat, and a main surface for positioning the chip 1 on the holder 11 in the thickness direction when the chip 1 is mounted on the concave mounting portion 12 of the holder 11 shown in FIG. Side reference plane. As shown in FIG. 3, each side of the outer peripheral surface of the chip 1 formed in a substantially triangular shape in a plan view has a predetermined angle with the central portion 1 p of the main surface except for the vicinity of the cutting edges 301 at both ends. The above-described side support surfaces 1q intersecting with each other (for example, at right angles) are formed.

Then, as shown in FIG. 4C, the convex portion 1b in each concave portion 1c is formed so that the top portion protrudes from the extension surface of the rake face 302. Thus, when the chips D generated by the cutting blade 301 are discharged along the rake face 302, the chips can be reliably pressed against the convex portion 1b, and the effect of cutting the chips is improved. In addition, the convex portion 1
b protruding from the extension surface is the chip body 1a
Is smaller than the width of the concave portion 1c in the thickness direction. Further, the convex portion 1b is provided in the concave portion 1 of the side support surface 1q.
It is formed so as not to protrude more than the extension to the c side.
This is to prevent the chip 1 from rattling if the protrusion 1b projects beyond the side support surface 1q when the chip 1 is mounted on the mounting portion 12 in FIG. .

The bottom surface 1f of the concave portion 1c is formed substantially parallel to the side support surface 1q. With the direction along the circumference of the chip body 1a as the axial direction, the axial cross-sectional shape of the projection 1b is as follows:
As shown in FIG. 4 (b), the taper surface 1t is formed so that the width at the distal end side is narrower than the width at the distal end side.
It has been. By doing so, cracks and the like are less likely to occur at the boundary between the tapered surface 1t and the bottom surface 1f when a powder compact is produced by press molding.

Further, the tip surface 1 of the convex portion 1b on the cutting blade 301 side
m is a tapered surface. Thereby, as shown in FIG. 4C, the pressing of the chips D to the convex portions 1b is performed more smoothly.

In the direction along the circumference of the tip body 1a, a distance l1 from the cutting edge 301 to the front edge of the projection 1b is set.
Is preferably adjusted in the range of 0.3 to 1.5 mm. l
If 1 is less than 0.3 mm, the resistance when the chips D ride on the convex portions 1b becomes too large, and the smooth discharge of the chips D may be hindered. Conversely, l1 is 1.5mm
If it is larger than this, the chips D may not curl so much, and the effect of deformation and division by the projection 1b may be insufficient.

Further, the distance l2 from the cutting edge 301 to the rear edge of the projection 1b in the direction along the side support surface 1q.
Is preferably adjusted in the range of 2 to 6 mm. l2 is 2m
If it is less than m, it is not possible to secure a sufficient space for forming the concave portion 1c and the convex portion 1b. Forming the concave portion 1c and the convex portion 1b under the condition that l2 exceeds 6.0 mm is as follows.
Often this is virtually impossible with normal sized chips.

The depth d of the concave portion 1c is 0.3 to 2.0 mm, preferably 0.3 to 1 mm when viewed with reference to the extension surface of the rake face 302 (the rake face side cutting edge forming area). .
It is adjusted in the range of 0 mm. By setting the depth of the concave portion 1c in this range, the effect of preventing the press punch from being broken as described above with reference to FIG. 1 is further enhanced, and the production of the chip 1 by die press described later becomes further easier. If the depth of the concave portion is less than 0.3 mm, the pressing area of the convex portion 1b on the chip main surface side may be insufficient, and the formation of the convex portion 1b may not be performed properly. On the other hand, when the depth of the concave portion 1c exceeds 2 mm, the concave portion 1c is relatively large with respect to the chip main body 1a as shown by a broken line in the figure, taking into account the general dimensions of this type of throw-away chip. As a result, the thickness j of the chip main body 1a in the direction along the main surface is insufficient at a position corresponding to the bottom edge of the concave portion 1c, which may cause a problem that the mechanical strength of the portion is insufficient.

The indexable tip 1 is made of a metal-ceramic composite material such as a cemented carbide or cermet, and is manufactured by a powder metallurgy technique. Specifically, the raw material powder is formed by die press molding in the thickness direction to form a powder compact, which is formed at 1400 to 1600 ° C.
And then, if necessary, subjecting the outer surface to processing such as polishing.

Here, in order to obtain the powder compact PC by die press molding in the thickness direction, the powder compact PC after pressing must be placed on one side of the die hole inner surface corresponding to the pressing direction. It must have an outer peripheral surface shape that can be released from the die hole by relatively sliding in the direction. Accordingly, the shape of the outer peripheral surface of the throw-away tip 1 obtained by firing the powder compact PC is as follows:
Regardless of the cross section in the thickness direction, any one of the following three conditions must be met without exception (see FIG. 2).

The cross-sectional outline is substantially parallel to the reference line O. In FIG. 2A, the outline part P1 appearing on the right side of the cross section S corresponds to this. Specifically, FIG.
Both side surfaces in the AA cross section of (b) (all cross the side support surface 1q) can be exemplified. The distance L from the reference line O to the cross-sectional outline portion monotonically decreases from one side of the reference line O to the other side. For example, a case where a punch taper is provided on the inner surface of the die hole corresponding to both side surfaces of the AA cross section. There is a maximum point U where the distance L from the reference line O is the largest in the middle of the cross-sectional outline, and both side portions P of the maximum point U
The distance L from the reference line O monotonically decreases as both a and Pb move away from the maximum point U. In FIG. 2A, the outline P3 shown on the left side of the cross section S corresponds to this. Specifically, a side surface portion corresponding to the concave portion 1c and the convex portion 1b in the BB cross section of FIG. 3B can be exemplified.

Then, in the above throw away tip,
As shown in FIG. 1A, since the convex portion 1b is formed so as to protrude from the bottom surface of the concave portion 1c, the height can be increased as compared with the case where the concave portion 1c is not formed. Then, as shown in FIG. 1B, the corresponding portion B of the convex portion 1b of the powder compact PC is pressed by a protruding portion 101a (or 102a) protruding from the outer edge of the front end surface of the press punch 101 (or 102). However, in accordance with the formation of the concave portion 1c, the protrusion 101a (or 102
a) can be made thicker, so that the protrusions 101a
Is unlikely to occur.

As shown in FIG. 3D, the rake face 302 may be formed in two or more steps. In this case, the first-stage surface, that is, the region including the cutting edge 301 is a rake face-side cutting edge forming region 302a. In the figure, the second stage surface 302
It can be seen that b forms the inner surface on the front side of the recess 1c. In addition, as shown in FIG.
It may be formed so as to straddle the concave portion 1c and the rake face 302.

FIG. 22A shows a rake face 302.
On the rake face side cutting edge forming area 302 connected to the cutting edge 301
In the figure, an example is shown in which the upper surface is formed in two steps, i.e., a and an inclined surface 302b connected to the rear side. The concave portion 1c is formed so as to be connected to the further rear side of the inclined surface 302b. FIG.
FIG. 2B shows an example in which the inclined surface 302b in FIG. 22A is replaced by an outwardly curved surface 302b '. Further, FIG. 22 (c) shows an example in which the entire rake face 302 is an inward radius face.

Next, as shown in FIG. 23A, the convex portion 1b can be formed with a round portion 1r at the connection with the bottom surface 1t of the concave portion 1c in the axial cross section. Further, a round portion 1r 'can be formed on both edges in the width direction of the top surface 1n.

Further, as shown in FIG. 23B, the top surface 1n of the projection 1b can be formed so as to be substantially parallel to the rake face 302 (or the rake face side cutting edge forming area 302a). . Accordingly, the chips deformed by riding on the convex portion 1b flow more smoothly, and thus the chips can be smoothly discharged. In addition, as shown in FIG. 23C, the bottom surface 1t of the concave portion 1c is formed.
May be formed so as to be substantially parallel to the rake face 302 (or the rake face side cutting edge forming area 302a). Further, a round portion 1r ″ may be formed at the intersection of the tip surface 1m and the top surface 1n of the convex portion 1b.

The powder compact for producing the chip 1 is as follows:
Since it is manufactured by die pressing in the thickness direction, FIG.
As shown in (a) and (b), the die hole 1 of the die 100
00a (cavity) by changing the filling amount of the raw material powder, a molded body PC (in other words, a chip) having substantially the same outer shape in plan view and different thicknesses from each other can be placed in the same die 100. And punches 101 and 102
Can be manufactured in pairs.

(Embodiment 2) Chip 1 shown in FIGS. 7 and 8
In the center of the chip 1, the thickest central part 2
A reference thickness (for example, 4 to 5 mm) is provided on one main surface side (hereinafter referred to as a main A surface) so as to protrude in a step shape. Further, at the three apexes of the triangular tip 1, a cutting edge portion 5 that is thinned in a step shape from the central portion 2 is formed, and this cutting edge portion 5 is mainly a thin portion at the center side. 6 and a thick portion 7 on the distal end side that is thicker than the thin portion 6. That is, the thick portion 7 is separated from the thin portion 6 by a step 8.
And a protruding portion 9 protruding to the main A surface side through the thin portion 6 by the height of the protruding portion 9.
In addition, the concave portion 1 c and the convex portion 1 b are formed at positions corresponding to the thin portion 6, and the cutting blade 301 is formed at the leading edge of the thick portion 7.

The thickness of the thin part 6 is, for example, about 2.5 mm, and the thickness of the thickest part of the thick part 7 is, for example, 3.0 m.
m. The thick portion 7 is provided in a radial direction from the top of the chip 1 in a width of, for example, about 1.5 mm (width on the upper surface of the step). Also, in FIG.
The height of the raised portion 9, that is, the height of the step 8, which is the difference between the thick portion 7 and the thin portion 6, is, for example, approximately 0.5 mm. The thickness is increased.

The surface of the thick portion 7 on the side of the main A surface, that is, the surface of the raised portion 9 is ground, for example, to have a ground surface having a center line average line roughness of about 0.2 μm Ra specified in JIS. However, since the surface on the main A side of the thin portion 6 is not ground, it has a baked surface (sintered surface) as it is when baked. On the other hand, the main surface opposite to the main A surface of the chip 1 (hereinafter referred to as the main B surface) is a flat surface having no irregularities unlike the main A surface side, and is ground to, for example, about 0.2 μmRa. ing. Moreover, the corner part (corner part) of the thick part 7
Is rounded to conform to the groove bottom shape.

Hereinafter, a method for manufacturing the chip 1 will be described. First, the raw material powder of the chip 1 is a raw material powder of a metal-ceramic composite material such as a cemented carbide or a cermet as described above. For example, when a WC-Co-based cemented carbide is used, WC 80 to 95 wt. Parts and 5-10 parts by weight of Co, about 2% by weight of a paraffinic resin was added as a binder,
Powder granulated by a spray drying method or the like can be used.

Then, the material powder is filled in a die press. As shown in FIG. 9 (FIG. 4 is a schematic view with emphasis on the characteristic portions), this die press device has a pair of upper and lower split dies 2 corresponding to the central portion 2 of the chip 1 (FIG. 7).
21, 222, a pair of upper and lower split dies 2 corresponding to the cutting blade portion 5
23, 224. The portion corresponding to the raised portion 9 is fitted to the split mold 223 on the upper side. further,
The portions corresponding to the concave portions 1c and the convex portions 1b (FIG. 3 and the like)
It is included in the upper and lower split dies 223 and 224. Here, the upper split dies 221 and 223 hold the upper press punch and the lower split die 22
2, 224 constitute a lower press punch.

First, as shown in FIG.
In the die hole 232 of the die 231 having a taper corresponding to the taper shape of the side support surface 1q of
Fill. At this time, the upper and lower split dies (split punches) 221 to 224 corresponding to the central portion 2 and the cutting blade portion 5 are arranged such that the intervals between the upper and lower split dies 221 to 224 are changed according to the thickness of each part. Is set. The height of the filled material powder P is substantially flush with the surface of the die plate 231 due to the operation of a not-shown abrasion feeder or the like.

Next, as shown in FIG. 9 (b), the drive shaft of the die press is driven by a motor in the vertical direction, and the distance between the split dies 221 and 222 and the split dies 223 and 224 are also determined.
The split molds 221 to 224 are moved while keeping the interval between them constant. Then, as shown in FIG. 9 (b), the upper and lower split dies 221 and 222 and the upper and lower split dies 223 and 224 are relatively approached in the axial direction and stopped at a desired chip 1 shape position. Next, as shown in FIG. 9C, pressing is performed at a predetermined pressure. As a result, the total compression stroke of the split dies 221 and 222 that press the thick central portion is larger than the full compression stroke of the split dies 223 and 224 that also press the thin cutting edge portion. As a result, a compact PC having a substantially uniform density regardless of the wall thickness can be obtained. For example, after the upper split molds 221 and 223 are retracted, the molded body PC is taken out by being pushed up by the lower split molds 222 and 224, sintered at a predetermined temperature, and in a predetermined tolerance range (thickness direction). ± 0.05mm, outer circumference ± 0.1mm)
And the chip material (blank) inside.

The pressing pressure applied to the main surface of the molded body PC is set so that the same pressure is applied to the thick and small portions, specifically, a pressure of 1 to ² t / cm ² . Is good. In this case, the powder compression ratio between the state of FIG. 9B and the state of FIG. 9C after pressing is set to about 2 to 4. And each split mold 221,
The compression stroke of 222 or the split dies 223 and 224 is adjusted so that the conditions of the pressing pressure and the powder compression ratio are satisfied.

Next, the chip material is ground. Specifically, the center A surface side of the central portion 2 and the thick portion 7 of the chip material, the tip side of the thick portion 7 and the entire main B surface side are ground (for example, 0.2 μm Ra). Smooth the surface and provide the desired high precision dimensions. Furthermore, the thick portion 7
The tip 1 is subjected to a rounding process or the like to complete the chip 1.

The tip 1 of the present embodiment manufactured in this manner has a structure in which the cutting edge portion 5 is provided with the protruding portion 9, so that its size (thickness of the thick portion 7) is adjusted according to the grooving width. When finishing with high accuracy, compared to conventional inserts,
There is an advantage that the amount of grinding is small and the processing is easy. That is, conventionally, as shown in FIG. 10 (a), on the main A surface side (lateral flank side), the entire surface of the cutting edge portion (the hatched portion in FIG. 10) must be ground. In the present embodiment, as shown in FIG. 10B, there is an advantage that only the surface of the raised portion 9 (shaded portion in FIG. 10) needs to be cut.

When the chip 1 of the present embodiment is manufactured, even if the chip 1 has irregularities such as large steps, the chip 1 is pressed and sintered using a plurality of split dies 221 to 224 according to the irregularities. It is easy to manufacture. In particular, since the split molds 221 to 224 corresponding to the unevenness are moved and pressed, the uneven shape can be formed satisfactorily. Also, since the surface 6a on the main A surface side of the thin portion 6 and the main B surface of the chip 1 are substantially parallel, the pressing pressure in the thin portion 6 becomes uniform, and warpage and distortion are suppressed. is there. In the thick portion 7 before the grinding process, the surface on the main A surface side and the main B surface of the chip 1 may be parallel to each other, similarly to the thin portion 6.

In this embodiment, the surface of the raised portion 9 is ground in order to ensure high dimensional accuracy. However, when the dimensional accuracy is not so required, the grinding of the surface of the raised portion 9 is omitted. Is also good. In this case, the surface of the raised portion 9 also becomes a sintered surface. Further, in the present embodiment, the thickness of the thin portion 6 is constant, but the thickness may be gradually changed (for example, increased) toward the distal end side as shown in FIG.

(Embodiment 3) Next, Embodiment 3 will be described. The description of the same parts as in Embodiment 2 will be omitted or simplified.

In this embodiment, as shown in FIG. 12, a substantially triangular chip 32 having a cutting edge portion 31 having no raised portion is produced by using a die press device. Hereinafter, the manufacturing method will be briefly described. First, chip 32
Are the same as those in the first embodiment.
As shown in FIG. 13 (FIG. 8 schematically shows a characteristic portion with emphasis on a characteristic portion), a die press device for pressing this powder has a pair of upper and lower split dies 236 corresponding to the central portion 33 (FIG. 12). , 237, upper and lower 1 corresponding to the thin cutting blade portion 31
A pair of split molds 238 and 239 are provided. Hereinafter, the manufacturing procedure will be described.

First, as shown in FIG.
The above-mentioned material powder P is filled in the die hole 242 of 41. At this time, the center part 33 and the cutting blade part 31 (FIG. 12)
In the upper and lower split dies 236 to 239 corresponding to the above, the intervals between the upper and lower split dies 236 to 239 are arranged according to the thickness of each part. That is, the interval between the upper and lower split dies 238 and 239 corresponding to the thin cutting edge portion 31 is narrow, and the interval between the upper and lower split dies 236 and 237 corresponding to the central portion 33 is wide. That is, the filling depth of the powder is small in the former,
It is larger in the latter.

Next, as shown in FIG. 13 (b), each of the split dies 236 to 239 is fixed while keeping the distance between the upper and lower split dies 236 and 237 and the corner between the upper and lower split dies 38 and 39 constant. Move. Then, as shown in FIG. 13C, the upper and lower split dies 236 and 237 and the upper and lower split dies 238 and 239 are moved closer to each other and stopped at a desired chip 32 shape position. Press. When the pressing is completed, the molded body PC is taken out and fired to produce a chip material. The obtained chip material has a central part 33 and a cutting edge part 3.
The main A surface side, the front end side of the cutting blade portion 31, and the entire main B surface side are ground to complete the chip 32 in FIG.

(Embodiment 4) Next, Embodiment 4 will be described, but the description of the same parts as in Embodiment 2 will be omitted or simplified. In this embodiment, as shown in FIG. 14, a substantially triangular chip 5 having a thick central portion 51 and a thin cutting edge portion 52 having no protruding portion is formed by using a die press device.
3 is produced. Hereinafter, the manufacturing method will be briefly described. First, materials for manufacturing the chip 53 are as follows.
This is the same as the second embodiment.

The die press for pressing this powder is as follows:
As shown in FIG. 15, the split mold 255 has a flat upper surface.
And a split mold 256 corresponding to the lower central portion 51 and a split mold 257 corresponding to the cutting edge portion 52. The manufacturing procedure will be described below in order. First, as shown in FIG. 15A, the above-described material powder P is filled in the die hole 262 of the die 261. At this time, each split mold 251 to 253
Are arranged according to the thickness of the central portion 51 and the cutting edge portion 52 of the tip 53.

Next, as shown in FIG. 15B, the upper and lower mold halves 255 to 257 are moved so as to approach each other to gradually compress the material powder and stop at a desired position of the chip 53. To press. When the pressing is completed, the molded body PC is taken out and fired to produce a chip material. The chip material is ground to form chips 53. In this embodiment, there is an advantage that the same effects as those of the second and third embodiments can be obtained while using the split dies 256 and 257 only for the lower punch.

(Embodiment 5) Next, Embodiment 5 will be described, but the description of the same parts as in Embodiment 2 will be omitted or simplified. FIG. 16A shows a chip according to this embodiment.
As shown in (b), the chip 71 has a substantially triangular shape.
On both main surface sides, there is a step from the central portion 72 to the cutting edge portion 75. Further, as shown in FIG. 16C, the cutting edge portion 75 includes a thin portion 73 and a thick portion 74 on the distal end side.
, And has raised portions 76 and 77 on both main surface sides of the thick portion 74. The surfaces on the main surfaces of the raised portions 76 and 77 are ground surfaces, and the surfaces on both main surfaces of the thin portion 73 are burnt surfaces.

In this chip 71, the step on one main surface side is large, but the step on the other main surface side is small. Therefore, as shown schematically in FIG. Then, it can be manufactured by a die press apparatus in which one split mold 281 is arranged at the top of the figure and two split molds 282 and 283 are arranged below.

It should be noted that the present invention is not limited to the above-described embodiment at all, and it is needless to say that the present invention can be implemented in various modes without departing from the gist of the present invention. For example, in the first to fifth embodiments, the case where a substantially triangular chip is manufactured using a cemented carbide has been described. However, the present invention can be similarly applied to a superhard tool material such as cermet and ceramics. Further, the throw-away away chip 1 of the present invention may be formed, for example, in a parallelogram shape as shown in FIGS. 18 (a) and (b), or in a square shape as shown in FIGS. 19 (a) and (b). Or Figure 20
It can be formed in a plate shape having various plane shapes such as a trapezoidal shape.

[Brief description of the drawings]

FIG. 1 is an explanatory view of an operation of a throw-away tip of the present invention.

FIG. 2 is an explanatory diagram of an outer peripheral surface shape pattern of a throw-away tip of the present invention.

FIG. 3 is a perspective view, a plan view, and an enlarged perspective view of a main part of a chip according to a first embodiment, and a schematic view showing some modified examples of a rake face.

FIG. 4 is a more detailed explanatory view of a main part of the chip of FIG. 3;

5A and 5B show a method of using the chip of Example 1, wherein FIG. 5A is a perspective view showing a state where the chip is attached to a holder, and FIG.
FIG. 4 is an explanatory diagram showing a processing state.

FIG. 6 is an explanatory view showing an example of a mode of attaching a chip to a holder.

FIG. 7 is a plan view and a front view of a chip according to a second embodiment.

FIG. 8 is a side view, a plan view, and a front view showing an enlarged cutting edge portion of the tip according to the second embodiment.

FIG. 9 is an explanatory view showing a procedure for manufacturing the chip of the second embodiment.

FIG. 10 is an explanatory view showing the cutting position of the insert of Example 2 in comparison with the insert of the conventional example.

FIG. 11 is a conceptual diagram showing a modification of the chip of the second embodiment.

FIG. 12 is a plan view of a chip according to a third embodiment.

FIG. 13 is an explanatory view showing the procedure for manufacturing the chip of the third embodiment.

FIG. 14 is an explanatory view showing the shape of a chip according to a fourth embodiment.

FIG. 15 is an explanatory view showing a procedure for manufacturing the chip of the fourth embodiment.

FIG. 16 is a plan view, a side view, and an enlarged explanatory view of a main part of a chip according to a fifth embodiment.

FIG. 17 is an explanatory view illustrating a method for manufacturing a chip of Example 5;

FIG. 18 is a plan view and a side view showing a modified example of the chip of the present invention.

FIG. 19 is a plan view and a side view showing another modified example of the chip of the present invention.

FIG. 20 is a plan view showing still another modified example of the chip of the present invention.

FIG. 21 is a diagram illustrating the operation of the method for manufacturing a chip according to the present invention.

FIG. 22 is a side view showing some modified examples of the rake face in the chip of the present invention.

FIG. 23 is an explanatory view showing some modified examples of the shape of the convex portion in the chip of the present invention.

FIG. 24 is an explanatory diagram of a conventional technique.

FIG. 25 is another explanatory diagram of the prior art.

FIG. 26 is another explanatory view of the conventional art.

[Explanation of symbols]

1, 32, 53, 71 Throwaway tip (tip) 1b Convex portion 1c Concave portion 2,33,51,72 Central portion 5,31,52,75 Cutting edge portion 6,73 Thin portion 7,74 Thick portion 8, 35 Step 9,76,77 Ridge 301 Cutting edge 302 Rake surface 303 Flank

Claims (10)

[Claims] 1. A substantially plate-like shape as a whole, and a pair of a rake face and a flank formed adjacent to each other in the circumferential direction is formed on an outer peripheral surface thereof or a plurality of pairs are formed along the circumferential direction. A chip body in which a cutting edge in the thickness direction is formed at an intersection of the paired rake face and the flank face, and the outer peripheral surface of the chip body has the cutting edge with respect to the rake face. A concave portion is formed so as to be continuous with the chip body from the opposite side, and the concave portion has a shape open to at least one end surface in the thickness direction of the chip body (hereinafter, the end surface in the thickness direction is referred to as a main surface). In addition, in the form in which the whole or a part is located in the concave portion, a convex portion is formed so as to protrude from the bottom surface of the concave portion, and further, when a powder compact having a shape corresponding to the chip body is considered. The powder compact is in the thickness direction. The outer peripheral surface of the chip main body and, consequently, the outer peripheral surface of the powder compact are relatively slid in one of the directions corresponding to the pressing direction with respect to the inner surface of the die hole of the press die so as to be obtained by die press molding. A throw-away tip, wherein the tip has a shape capable of being released from the die hole. 2. The throw-away tip according to claim 1, wherein a top of the projection is formed so as to protrude from an edge position of a side of the rake face connected to the recess in the projection direction of the projection. 3. A plane-shaped rake face-side cutting edge forming area connected to the cutting edge is formed on the rake face, and when the rake face-side cutting edge forming area is extended to the concave side, the convex face is formed. 3. The indexable insert of claim 2, wherein the top of the portion protrudes beyond its extension surface. 4. A region of at least one of the main surfaces of the tip body, including an edge corresponding to the cutting edge of the main surface (hereinafter, this region is referred to as a main surface side cutting blade forming region).
The throw-away tip according to any one of claims 1 to 3, wherein the thickness of the tip is increased so as to protrude from a region adjacent to the main surface on the main surface. 5. A flat rake face-side cutting edge forming area connected to the cutting edge is formed on the rake face, and the concave portion is viewed with reference to an extension surface of the rake face-side cutting edge forming area. The throw-away tip according to any one of claims 1 to 4, wherein the depth at that time is adjusted in a range of 0.3 to 2.0 mm. 6. The method for producing a throw-away chip according to claim 1, wherein the powder molded body that has been press-molded is fired. A cavity is formed by the inner surface of the die hole and each punch surface of the press punch inserted into the die hole from above and below,
A die press apparatus for manufacturing a powder compact to be the throw-away chip by pressing the upper and lower press punches relatively close to each other and press-molding the raw material powder filled in the cavity. A method for manufacturing a throw-away chip, wherein the powder is compressed in the thickness direction of the powder compact to be formed by the upper and lower press punches. 7. The method according to claim 6, wherein by changing a filling amount of the raw material powder into the cavity, a throw-away chip having substantially the same outer shape in plan view and different thicknesses is manufactured. Method for manufacturing indexable inserts. 8. The powder compact has two or more portions having different thicknesses, and a plurality of at least one of an upper press punch and a lower press punch is provided corresponding to the portions having different thicknesses. 8. The throw according to claim 6, wherein the divided punches compress the powder in the cavity with different strokes depending on the thickness of each corresponding part of the powder compact to be obtained. Manufacturing method of away chip. 9. A throw-away tip according to claim 1, further comprising: a tip holder formed in a rod shape and having a tip portion to which the throw-away tip is detachably attached. And the tool unit. 10. A flat reference surface extending along a longitudinal direction of the tip holder is formed on an outer surface of the tip holder, and the indexable tip has a cutting edge substantially parallel to the reference surface. And, along the longitudinal direction of the reference plane, the cutting blade, the rake face and the recess are arranged in this order from the tip side, so that it is detachably attached to the chip holder. Further, in a state where the throw-away tip is attached to the tip holder, the reference surface is substantially horizontal, and when the tip holder is held in a posture in which the projecting direction of the protrusion is upward, the reference surface The convex portion of the throw away tip in a direction orthogonal to
The tool unit according to claim 9, wherein a height of the tool unit is adjusted so as to protrude from the cutting edge position and not to protrude from a rear upper edge position of the concave portion.