Method of and a device for the compaction of a powder into a cutting insert green body

Abstract

A device for manufacturing a cutting insert green body by compacting a powder includes a first punch, a second punch having a punch edge that has a curvature around the circumference of the punch edge that is at least partially non-perpendicular with a pressing axis of the device, a first die part, and a second die part. When the first and second die parts are joined together when filling the die with powder, one of the first and second die parts is on top of the other and, when the device is in a position ready for filling of powder into the die, the device presents a cavity defined by the lower die part, a punch being introduced into the lower and upper die part. An opening in an upper end surface of the upper die part enables filling of the powder into the cavity.

Claims

1. A method of compacting a powder into a cutting insert green body comprising the steps of: providing a compaction device including a first punch; a second punch that presents an abutment surface for abutment with the powder to be compacted, an outer peripheral surface, and a punch edge disposed at an intersection between the abutment surface and the outer peripheral surface, wherein the punch edge presents a predetermined curvature around the circumference of the second punch; a first die part presenting a chamber having an inner peripheral surface which corresponds to a peripheral surface of a cutting insert green body to be compacted in said first die part, a bore for receiving said first punch, said bore extending from an opening in a first end surface of the first die part to said chamber, and an opening region extending with an expanding cross-section from said chamber to an opposite second end surface of the first die part and defining an opening in said opposite second end surface; a second die part presenting a bore for receiving said second punch, said bore extending from an opening in a first end surface of the second die part to a second end surface thereof, thereby defining an opening in said second end surface, wherein an edge that defines said opening in the second end surface of the first die part has a curvature corresponding to the predetermined curvature of said punch edge of the second punch; arranging the second end surface of the first die part and the second end surface of the second die part contiguously such that said opening in the second end surface of the first die part meets said opening of the second end surface of the second die part; positioning the device such that one of said first and second die parts is contiguously arranged above the other die part; arranging said first end surface of the one of the die parts being arranged above the other die part such that it extends rectilinearly in at least one direction; introducing one of said punches into the bore of the one of the die parts being arranged below the other die part, wherein said predetermined curvature of the punch edge of the second punch is at least partly non-perpendicular to a pressing axis of the device and that the edge of the opening in the second end surface of the first die part presents a corresponding curvature with regard to said pressing axis; and filling powder into a cavity defined by the one of the die parts being arranged below the other die part, the punch introduced therein and the one of the die parts being arranged above the other die part by introducing the powder through the opening in the first end surface of the one of the die parts being arranged above the other die part; and compacting the powder.

2. A method according to claim 1, wherein the step of compacting the powder includes introducing into said cavity by advancing the other of said first and second punches through the opening in the first end surface of the one of the first and second die parts being arranged above the other die part towards said chamber to a final compacting position.

3. A method according to claim 1, wherein the step of compacting the powder includes introducing into said cavity by advancing the second punch through the second die part until the punch edge is at a distance from said inner peripheral surface of said chamber of the first die part so short that an edge of the compacted green body will be formed in the region in which said punch edge is adjacent to said inner peripheral surface.

4. A method according to claim 3, wherein the second punch is advanced until the distance between the punch edge and the inner peripheral surface of the chamber in the first die part is equal to or less than 50 m, equal to or less than 30 m, equal to or less than 10 m, or equal to or less than 5 m.

5. A method according to claim 1, further comprising the steps of exposing the compacted cutting insert green body by retracting the first die part from the second die part, and displacing the compacted green body from the first die part through the opening in the second end surface thereof.

6. A method according to claim 1, further comprising the step of providing a region around said opening in the second end surface of the second die part with a curvature corresponding to the curvature of the edge that defines the opening in the second end surface of the first die part, such that the second surface of the second die part will be in a sealing relation with said edge of the first die part when the first die part is contiguously arranged in relation to the second die part.

7. A method according to claim 1, further comprising the step of providing a powder-filling device and positioning it on top of said opening in the first end surface of the upper die part or removing it from said position by permitting it to slide on said first end surface of the upper die part in said direction in which said surface extends rectilinearly.

8. A method according to claim 1, wherein the compacted cutting insert green body has the shape of a positive cutting insert, and that the inner peripheral surface of said chamber in the first die part has a corresponding shape, with a cross section cross wise to the pressing axis that increases towards the opening in the second end surface of the first die part.

9. A device for manufacturing a cutting insert green body by compacting a powder, said device comprising: a first punch; a second punch that presents an abutment surface for abutment with the powder to be compacted, an outer peripheral surface, and a punch edge at an intersection between the abutment surface and the outer peripheral surface, wherein the punch edge presents a predetermined curvature around the circumference of the second punch; a first die part, presenting a chamber having an inner peripheral surface which corresponds to a peripheral surface of a cutting insert green body to be compacted in said first die part, a bore for receiving said first punch, said bore extending from an opening a first end surface of the first die part to said chamber and an opening region extending with an expanding cross-section from said chamber to an opposite second end surface of the first die part and defining an opening in said opposite second end surface; a second die part, presenting a bore for receiving said second punch, said bore extending from an opening in the first end surface of the second die part to a second end surface of the second die part, thereby defining an opening in said second end surface, wherein an edge that defines said opening in the second end surface of the first die part has a curvature corresponding to the predetermined curvature of said punch edge of the second punch, the second end surface of the first die part being configured to be contiguously arranged in relation to the second surface of the second die part such that said opening in the second end surface of the first die part meets said opening in the second end surface the second die part, wherein, when the first and second die parts are contiguously arranged to each other in connection to filling of powder into the die, one of said first and second die parts is arranged above the other, said first end surface of the one of the die parts being arranged above the other die part extends rectilinearly in at least in one direction, said predetermined curvature being at least partly non-perpendicular to a pressing axis of the device and that the edge of the opening in the second end surface of the first die part presents a corresponding curvature with regard to said pressing axis; and when the device is in a position ready for filling of powder into the die, it presents a cavity defined by the one of the die parts being arranged below the other die part, a punch being introduced therein and the one of the die parts being arranged above the other die part.

10. A device according to claim 9, wherein the first end surface of the one of the die parts being arranged above the other die part is flat.

11. A device according to claim 9, wherein the first surface of the one of the die parts being arranged above the other die part extends in a plane perpendicular to the pressing axis.

12. A device according to claim 9, further comprising a powder-filling device, arranged to slide on said first surface of the one of the die parts being arranged above the other die part in said at least one direction in which the first surface extends rectilinearly, to and from a powder-filling position on top of said opening in the first surface of the one of the die parts being arranged above the other die part.

13. A device according to claim 9, wherein the second punch is arranged so as to be advanced through the second die part to a final compaction position at which the punch edge is at a distance so short from the inner peripheral surface of said chamber of the first die part that, upon compaction of a powder introduced into said cavity, an edge of the compacted green body will be formed in the region in which said punch edge is adjacent to said inner peripheral surface.

14. A device according to claim 13, wherein the second punch is arranged to be advanced until the distance between the punch edge and the inner peripheral surface of said chamber is equal to or less than 50 m, equal to or less than 30 m, equal to or less than 10 m, or equal to or less than 5 m.

15. A device according to claim 13, wherein, when the second punch is in a final compaction position, the distance in the direction of the pressing axis from the level of the punch edge to a level of the edge that defines the opening in the second surface of the first die part is within the range of 10-500 m.

16. A device according to claim 9, wherein a region around said opening in the second end surface of the second die part has a curvature corresponding to the curvature of the edge that defines the opening in the second end surface of the first die part, such that the second end surface of the second die part will be in sealing relation with said edge of the opening in the second end surface of the first die part when the first and second die parts are contiguously arranged.

17. A device according to claim 9, wherein, when the first and second die parts are contiguously arranged, the second surface of the second die part overlaps the opening in the second end surface of the first die part, thereby forming an overlapping rim around said opening said second end of the first die part.

18. A device according to claim 9, wherein the die includes an outer die part that at least partially laterally encloses the first and second die parts when those are contiguously arranged, and that the outer die part has an upper surface that coincides with the first surface of the one of the die parts being arranged above the other die part when the latter is contiguously arranged in relation to the one of the die parts being arranged below the other die part and the device is in a position ready for filling of powder into said cavity.

19. A device according to claim 9, wherein the one of the die parts being arranged above the other die part presents an extension that overlaps the lower die part when the first and second die parts are joined and that comprises a lateral opening which is exposed when the one of the die parts being arranged above the other die part is retracted from the position in which it is contiguously arranged in relation to the other die part, such that a compacted green body, which is exposed as a result of said retraction of the one of the die parts being arranged above the other die part and a displacement of the green body out of the first die part in the direction of the pressing axis, is laterally exposed through said opening.

20. A device according to claim 9, wherein the cutting insert green body has the shape of a positive cutting insert, and that the inner peripheral surface of said chamber in the first die part has a corresponding shape, with a cross section cross wise to the pressing axis that increases towards the opening in the second surface of the first die part.

21. A device according to claim 9, wherein the second die part is the one of the die parts arranged above the other die part.

22. A device according to claim 9, wherein the first die part is the one of the die parts arranged above the other die part.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Hereinafter, embodiments of the present invention will be described in detail with reference to the annexed drawing, on which:

(2) FIG. 1a-1b is a representation of a cutting insert the shape of which corresponds to a shape of a cutting insert green body to be produced in a device and by means of a method according to the present invention,

(3) FIG. 2a is a perspective cross section of a first embodiment of a device according to the invention,

(4) FIG. 2b is an exploded side view of a cross section of the embodiment shown in FIG. 2a,

(5) FIGS. 3a-3g is a series of figures showing the succeeding steps of the method according to an embodiment of the present invention for compacting a cutting insert green body by means of the abovementioned first embodiment of a compaction device according to the present invention, as seen in cross-section,

(6) FIG. 4a is a perspective cross section of a second embodiment of the device according to the invention.

(7) FIG. 4b is an exploded side view of a cross section of the embodiment shown in FIG. 4a,

(8) FIGS. 5a-5f is a series of figures showing the succeeding steps of the method according to an embodiment of the present invention for compacting a cutting insert green body by means of the abovementioned second embodiment of a compaction device according to the present invention, as seen in cross-section, and

(9) FIG. 6 is an enlarged representation of a detail of the an inventive device showing some essential parts of the device in a final compaction position of a second punch.

DETAILED DESCRIPTION OF THE INVENTION

(10) FIGS. 1a and 1b show a cutting insert green body 1 which could be produced by compaction of a powder by means of a device and a method according to the present invention. Typically, the cutting insert green body 1 is subjected to edge treatment and grinding followed by a sintering process in which it is further densified. In most cases, the sintered body is then provided with a suitable wear resistant coating, such as a carbide, nitride, carbonitride, oxide, or boride with any suitable contemporary technique, such as physical vapour deposition or chemical vapour deposition. The cutting insert is used for the machining of metal by milling, drilling or turning or by similar chip forming methods. The shape of the cutting insert corresponds to the shape of the compacted green body 1 from which it has been produced. What is hereby stated regarding the shape of the cutting insert green body 1 shown in FIGS. 1a and 1b is therefore also valid for the shape of a cutting insert produced from said green body.

(11) The cutting insert green body 1 shown in FIGS. 1a and 1b has the shape of a positive cutting insert, presenting an increasing cross section from a first end 2 thereof, to a second end 3 thereof. At the second end 3 of the green body 1 the latter presents a cutting edge 4 which runs around the circumference of the green body 1. The cutting edge 4 is defined by an intersection of the surface of the second end 3 and a peripheral surface 5 of the green body 1. The edge 4 has a curvature that is at least partly non-perpendicular to an axis x corresponding to the pressing axis that has been applied during the compaction of a powder into said green body 1. Partly non-perpendicular is hereby referred to as having a curvature, such that, for different angular positions around said axis x along said cutting edge around the circumference of the green body 1, the position of the cutting edge in the direction of the pressing axis differs.

(12) FIG. 2 shows a first embodiment of a device according to the present invention for producing a cutting insert green body like the green body 1 shown in FIGS. 1a and 1b. The device defines a press tool that comprises a first punch 6, a second punch 7, a first die part 8 and a second die part 9. It should be understood that parts of the device that are to be displaced during the operation of the device may be connected to actuators provided for that purpose. Such actuators, and the specific connection of said parts thereto, are not shown in the drawing, since it is regarded as ordinary design measures to be taken by a person skilled in the art.

(13) The second punch 7 presents an abutment surface 10 for abutment with the powder to be compacted, and an outer peripheral surface 11, and a punch edge 12 at the intersection between the abutment surface 10 and the outer peripheral surface 11, wherein the punch edge 12 presents a predetermined curvature corresponding to the curvature of the abovementioned cutting edge of the green body 1. Accordingly, the punch edge 12 presents a curvature that is at least partly non-perpendicular to the pressing axis x in the sense that it has a curvature, such that, for different angular positions along said cutting edge around the circumference of the green body 1, the position of the cutting edge in the direction of the pressing axis differs.

(14) The second punch 7 also presents a centre bore 13 extending in the longitudinal direction of punch 7, i.e. parallel with the pressing axis x, for the purpose of receiving a core pin 14. It should however be understood that the provision of a core pin and bores like the bore 13 in the second punch 7 is optional and not critical to the present invention.

(15) The first die part 8 presents a chamber 15, with an inner peripheral surface 16 which has a geometry that corresponds to the geometry of the peripheral surface 5 of the cutting insert green body 1 to be compacted in said first die part 8. Furthermore, the first die part 8 presents a bore 17 for receiving said first punch 6, said bore 17 extending from an opening 18 in a first end surface 19 of the first die part 8 to said chamber 15, and an opening region extending with an expanding cross-section from said chamber 15 to an opposite second end surface 20 of the first die part 8 and defining an opening 21 in said opposite second end surface 20.

(16) The second die part 9 presents a bore 22 for receiving said second punch 7. The bore 22 extends from an opening 23 in a first end surface 24 of the second die part 9 to a second end surface 25 thereof, thereby defining an opening 26 in said second end surface 25.

(17) An edge 27 that defines said opening 21 in the second end surface 20 of the first die part 8 has a curvature corresponding to the predetermined curvature of the abovementioned punch edge 12 of the second punch 7 in the sense that it has a corresponding curvature around the circumference of the opening 21 that it defines as has the punch edge 12 around the circumference of the second punch 7. Curvature may be referred to as a variation of the position for each incremental part of the edge 27 in the direction of the pressing axis x.

(18) FIG. 2a shows a first embodiment of the press tool of the present invention in a position ready for filling of powder into a cavity defined therein. The second end surface 20 of the first die part 8 is contiguously arranged in relation to the second end surface 25 of the second die part 9 such that said opening 21 in the second end surface 20 of the first die part 8 meets said opening 26 in the second end surface 25 of the second die part 9.

(19) When the first and second die parts 8, 9 are contiguously arranged in relation to each other in connection to the filling of powder into the die, one of said first and second die parts 8, 9 is above the other, thereby defining an upper die part having its first end surface turned upwards. In the first embodiment shown in FIGS. 2-3, the second die part 9 is above the first die part 8. The first end surface 24 of the second die part 9 thus forms an upper surface of the die and the opening 23 defines an upper opening of the die, through which a powder to be compacted may be introduced into said cavity, which is defined by the inner peripheral surface 16 of said chamber 15 of the first die part 8, an inner peripheral surface 28 of the bore 17 of the first die part 8, an end surface 29 of the first punch 6 introduced into said bore 17, and an inner peripheral surface 30 of the bore 22 in the second die part 9.

(20) The first end surface 24 of the second die part 9 is essentially flat and extends in a plane perpendicular to the pressing axis x. Preferably, the pressing axis x is vertical, and thus said plane is preferably horizontal.

(21) The die further comprises an outer die part 31 that laterally encloses the first and second die parts 8, 9 when those are joined. The outer die part 31 may be connected to, and form a unit together with, the lower die part. The outer die part 31 has an upper surface 32 that coincides with the first surface 24 of the second die part 9 when the latter is joined with the first die part 8 and the device is in a position ready for filling of powder into said cavity. The outer die part 31 may be provided primarily for the purpose of defining a table on which a powder-filling device may be positioned during operation of the device. However, it may also have possible further function, such as stabilizing function, and may therefore be referred to as a die part, such as when being connected to the lower die part.

(22) The second die part 9, presents an extension 34 that laterally overlaps the first die part 8 when the first and second die parts are joined and that comprises a lateral opening 35 which is exposed when the first and second die parts 8, 9 are retracted from each other, such that a compacted green body, which is exposed as a result of said retraction and a displacement of the green body out of the first die part 8 in the direction of the pressing axis x, is laterally exposed through said opening 35 (see in particular FIG. 3g). The extension 34 is in its turn connected to an actuator, not shown, located below the first die part 8. Other alternative solutions are of course feasible. According to one such alternative solution, not shown on drawing but within the scope of the present invention, the die part forming the upper die part presents an upper extension which extends above said first surface of the upper die part. Such an upper extension is connected to an actuator provided for the displacement thereof located above the die.

(23) FIGS. 3a-3g show essential steps of an embodiment of the method of the invention applied by means of the above-disclosed first embodiment of the device according to the present invention.

(24) FIG. 3a shows the device of the invention in a position ready for filling powder into the previously mentioned die cavity defined by the aforementioned peripheral surfaces 16, 28 and 30 and the end surface 29 of the first punch 6. The second punch 7 is retracted to a position above the first surface 24 of the second die part 9, leaving room for a powder-filling device 33 to be positioned on top of the opening 23 in the first end surface 24 of the second die part 9. The powder-filling device 33 may be regarded as forming part of the device of the invention. A further table 36 that laterally surrounds the outer die part 31 and has an upper surface in alignment with the upper surface 32 of the outer die part 31 is also shown and forms an optional part of the device.

(25) FIG. 3b shows a subsequent step in which the powder-filling device 33 is positioned on top of the opening 23 in the first end surface 24 of the second die part and executes the filling operation. In order to move the powder-filling device 33 from the laterally retracted position shown in FIG. 3a to the position on top of said opening 23 shown in FIG. 3b, the powder-filling device 33 is slid on the first end surface of the upper die part, i.e. the first end surface 24 of the second die part 9, and here also on the upper surface 32 of the outer die part 31 and the upper surface of the surrounding table 36. The first punch 6 is in a position inside the bore 17 of the first die part 8, but somewhat retracted in relation to the chamber 15 therein in order to enable receipt of a sufficient amount of powder in the cavity thereby defined in the die.

(26) FIG. 3c shows a subsequent compaction step in which the second punch 7, is being displaced downwards into the bore 22 in the second die part 9. The first punch 6 is displaced upwards through the bore 17 towards the chamber 15 in the first die part 8. Preferably, but not necessarily, the displacements of the first punch 6 and the second punch 7 are simultaneous.

(27) FIG. 3d shows the device in a final compaction position, in which the chamber 15 that defines the geometry of the cutting insert green body 1 to be formed is now defined by the inner peripheral surface 16 of the chamber 15 of the first die part, the upper end surface 29 of the first punch 6 and the abutment surface 10 of the second punch 7. Here, the method according to the invention comprises the step of compacting the powder introduced into said cavity by advancing the second punch 7 through the second die part 9 until the punch edge 12 is at a distance from said inner peripheral surface 16 of said chamber 15 of the first die part 8 so short that an edge, corresponding to a cutting edge of the cutting insert, of the compacted green body 1 will be formed in the region in which said punch edge 12 is adjacent to said inner peripheral surface 16.

(28) Reference is now being made to FIG. 6 that shows a detail of the device in an enlarged scale in a position corresponding to the one shown in FIG. 3d. In the final compaction position, the second punch 7 protrudes with the punch edge 12 a distance L into the first die part 8, such that the distance g between the punch edge 12 and the inner peripheral surface 16 of the chamber 15 is equal to or less than 10 m, or even more preferably equal to or less than 5 m (anywhere around the circumference of the second punch 7). Since the edge 27 defining the opening 21 in the second end surface 20 of the first die part 8 has a curvature corresponding to the curvature of the punch edge 12, the distance between the punch edge 12 and said edge 27 is more or less the same all around the circumference of the second punch 7. The distance L in the direction of the pressing axis x from the level of the punch edge 12 to the level of the edge 27 that defines the opening 21 in the second surface 20 of the first die part 8 is within the range of 1-500 m, preferably within the range of 100-300 m. Preferably, L10 m, and, depending on the geometry and size of the compacted body to be formed L50 m. Powder is to a high degree prevented from escaping through the gap g between the punch edge 12 and the inner peripheral surface 16 of the chamber 15 and there will be a very limited space in which escaped loose powder can be gathered. Thereby, the invention results in an advantageous suppression of any formation of a residual edge on the cutting insert green body 1, and a promotion of a production of a cutting insert with a cutting edge with a very small radius.

(29) From the level of the punch edge 12 to the level of the edge 27 defining the opening 21 in the second end surface 20 of the first die part 8, the inner peripheral surface 37 of the first die part 8 has an inclination angle relative the pressing axis x which depends on the inclination angle of the inner peripheral surface 16 of the chamber 15. Preferably, the inclination angle is the same for the inner peripheral surface 16 of the chamber 15 and the inner peripheral surface 37 of the opening region as seen at any cross section around in the circumference of the chamber 15. The inclination angle may vary around the circumference of the inner peripheral surface 37 of the opening region and the inner peripheral surface 16 of chamber.

(30) A region around the opening 26 in the second end surface 25 of the second die part 9 has a shape, i.e. a curvature around the circumference of said opening 26, corresponding to the curvature of the edge 27 that defines the opening 21 in the second surface 20 of the first die part 8, such that the second surface 25 of the second die part 9 will be in sealing relation with said edge 27 of the opening 21 in the second end surface 20 of the first die part 8 when the first and second die parts 8, 9 are joined. Thereby, powder is prevented from escaping into any possible space between the second surfaces 20, 25 of the first and second die parts 8, 9.

(31) When the first and second die parts 8, 9 are contiguously arranged in relation to each other, the second surface 25 of the second die part 9 overlaps the opening 21 in the second end surface 20 of the first die part 8, thereby forming an overlapping rim 38 around said opening 21 in said second end surface 20 of the first die part 8. The size of the rim 38 may vary around the circumference of the opening 21 in the second end surface 20 of the first die part 8, depending on the geometry of the cutting insert green body 1 to be compacted and the geometry of said opening 21. The size of the rim 38 thus depends on the distance L that the punch edge 12 of the second punch 7 projects into the first die part 8, the inclination angle and the gap k between the outer peripheral surface 11 of the second punch 7 and an inner peripheral surface 30 of the bore 22 in the second die part 9.

(32) FIG. 3e shows a subsequent step in which the first and second die parts 8, 9 are separated from each other. In this particular embodiment, separation is achieved by means of retraction of the second die part 9 from the first die part 8. However, it should be understood that this is a relative displacement, and that the separation could as well be achieved by a displacement of the first die part 8 or both die parts. This is only a matter of connecting the respective part to an actuator, and thereby making displacement thereof possible.

(33) FIG. 3f shows a subsequent step in which the first punch 6 and the second punch 7 are displaced in the direction of the pressing axis x relative the first die part 8 such that the compacted cutting insert green body 1 is displaced out of the first die part 8 through the opening 21 in the second end surface 20 of the first die part 8 and is exposed and laterally accessible through the opening 35 in the extension 34 of the second die part 9.

(34) FIG. 3g shows a further step according to which the punch that forms the upper punch, here the second punch 7, is further retracted as well as the core pin 14, such that the exposed cutting insert green body 1 is only supported by an upper end surface of the lower punch, here the first punch 6. The exposed cutting insert green body 1 can now get gripped by a device 39 for the removal of the green body 1 from the die. The removal device 39 may be any kind of robot or the like.

(35) FIG. 4 shows an alternative embodiment which differs from the first embodiment in the sense that the first die part 108 is positioned above the second die part 109, thereby defining an upper die part having its first end surface 119 turned upwards. The first punch 106 and the second punch 107 are identical to the ones disclosed with reference to the first embodiment. Thus, the second punch 107 has an abutment surface 110, a peripheral surface 111 and a punch edge 112. The first die part 108 presents a chamber 115 with an inner peripheral surface 116, a bore 117 extending from the chamber 115 to an opening 118 in a first end surface 119, an opening region extending from the chamber 115 to an opening 121 in an opposite second end surface 120, said opening being defined by an edge 127. The second die part 109 presents a bore 122 which extends from an opening 123 in first end surface 124 to an opening 126 in an opposite second end surface 125. What has previously been stated regarding the provision of the corresponding surfaces, openings, bores, extensions and actuators of the first embodiment is also valid for these surfaces, openings, bores, extensions and actuators in the second embodiment.

(36) The embodiment in FIG. 4 further differs from the one shown in FIGS. 2 and 3 in that it is the first die part 108 that comprises an extension 134 corresponding to the extension 34 carried by the second die part 9 in the first embodiment. Accordingly, also here it is the upper die part that presents said extension. However, it should be mentioned that, as an alternative to the design presented in both the abovementioned embodiments, the extension may be provided on the lower die part, provided that the upper die part is designed such that it still enables the filling of powder into the latter from a position on top thereof and removal of the compacted green body by, for example, a robot. The provision of extensions that connect the respective moving part with an actuator is a matter of choice with regard to the requested functionality, and may be varied widely within the scope of the present invention.

(37) When the die is in a position ready for filling of powder, the second end surface 120 of the first die part 108 is contiguously arranged in relation to the second end surface 125 of the second die part 109 such that the opening 121 in the first die part 108 meets the opening 126 in the second die part 109. A cavity is defined by inner peripheral surfaces 116, 128, 130 of the above-mentioned bores and chamber and the abutment surface 110 of the second punch 107, which projects from below into the bore provided in the second die part 109. The first end surface 119 of the first die part 108 forms a flat upper surface in which the abovementioned opening 118 is provided. An outer die part 131, that may or may not be directly connected to the lower die part, surrounds the first and second die parts 108, 109 laterally and presents an upper surface 132 which coincides with and is in alignment with the first end surface 119 of the first die part 108. A powder-filling device 133 is provided for the purpose of filling powder into said cavity through said opening 118 in the first end surface 119 of the first die part 108 from a position on top of said opening 118. The powder-filling device 133 reaches its operative position above the opening 118 by sliding on the first end surface 119 of the first die part 108 and on the upper surface 132 of the outer die part 131.

(38) FIGS. 5a-5f show essential steps of an embodiment of the method of the invention applied by means of the above-disclosed second embodiment of the device according to the present invention.

(39) FIG. 5a shows the device in a position ready for filling of powder into the cavity defined by the inner peripheral surfaces 116, 128, 130 of the chamber 115, the bore 117 and the bore 122 and the abutment surface 110 of the second punch 107. A further table 136 that laterally surrounds the outer die part 131 and has an upper surface in alignment with the upper surface 132 of the outer die part 131 is also shown and forms an optional part of the device. The powder-filling device 133 is located on the upper surface of the table 136 and is ready for sliding on that surface and the upper surface 132 of the outer die part 131 and the first end surface 119 of the first die part 108 to a position on top of said opening 118 in said first end surface 119. The first punch 106 is retracted from the first end surface 119 of the first die part 108 in order to enable the positioning of the powder-filling device 133 on top of said opening.

(40) FIG. 5b shows a subsequent step in which the powder-filling device 133 fills the abovementioned cavity with powder. The second punch 107 is in a position inside the bore 122 of the second die part 109, but somewhat retracted in relation to the chamber 115 therein in order to enable receipt of a sufficient amount of powder in the cavity thereby defined in the die. As an alternative, the second punch 107 could be in its final compaction position already at this stage, provided that the cavity defined by the die is yet large enough to accommodate the required amount of powder.

(41) FIG. 5c shows a subsequent compaction step in which the first punch 106, is being displaced downwards into the bore 117 in the first die part 108. The second punch 107 is displaced upwards through the bore 122 in the second die part 109 towards the chamber 115 in the first die part 108. Preferably, but not necessarily, the displacements of the first punch 106 and the second punch 107 are simultaneous.

(42) FIG. 5d shows the device in a final compaction position, in which the chamber 115 that defines the geometry of the cutting insert green body 1 to be formed is now defined by the inner peripheral surface 116 of the chamber 115 of the first die part, the end surface 129 of the first punch 106 and the abutment surface 110 of the second punch 107. Likewise to the first embodiment disclosed with reference to FIG. 3a-3g, the method according to the second embodiment of the invention comprises the step of compacting the powder introduced into said cavity by advancing the second punch 107 through the second die 109 and predetermined distance into the first die part 108 such that the punch edge 112 is at a distance from said inner peripheral surface 116 of said chamber 115 of the first die part 108 so short that an edge, corresponding to a cutting edge of the cutting insert, of the compacted green body 1 will be formed in the region in which said punch edge 112 is adjacent to said inner peripheral surface 116. In the region corresponding to the region shown in FIG. 6, the second embodiment preferably presents the same features as the first embodiment. However, FIG. 6 would have to be turned upside down to fully reflect the second embodiment presented in FIGS. 4-5.

(43) FIG. 5f shows a subsequent step in which the first die part 108 is retracted upwards relative the lower die part 109 in order to displace the compacted cutting insert green body 1 out of the first die part 108. A lateral opening 135 in the extension 134 of the first die part 108 makes the cutting insert green body accessible from a lateral position.

(44) FIG. 5g shows a further step in which the first punch 106 is retracted upwards from the compacted cutting insert green body 1 and the core pin 114 is retracted downwards from said body 1 in order to enable removal of the compacted green body 1 from the die by means of a device 139 for the removal of the green body 1 from the die. The compacted green body 1 is thus only supported by the abutment surface 110 of the second punch 107 when being gripped by said device 139.

(45) It should be understood that the above description of the invention is only by way of example and that the scope of protection is defined by the patent claims, and that alternative embodiments obvious to the person skilled in the art are included in the claimed scope of protection. Accordingly, the invention also includes solutions in which any of the abovementioned first and second die parts are further subdivided into two or more subparts. Furthermore, the first and second parts, though it is preferred in connection to the present invention, need not be separated from each other by displacement thereof in the direction of the pressing axis. If any such die part is subdivided into two or more subparts, such a die part may be removed from the other die part by separation of such subparts and displacement thereof in another direction than the pressing axis, such as in a direction perpendicular to the pressing axis. There may also be further punches, and subdivision of the abovementioned punches into several punches. Also the number of core pins is a matter of choice for the person skilled in the, as well as the connection of the respective die parts, punches and core pins to actuators for the displacement thereof.