EP3439815B1 - Method and apparatus for manufacturing hard metal green bodies - Google Patents

Description

The present disclosure relates to a method and an apparatus for producing a hard metal compact and a hard metal compact. The present disclosure also deals with the production of blanks for the sintering of components made of hard metals, in particular of cutting tools. Cutting tools can include cutting inserts, indexable inserts, and the like.

Carbide cutting tools are generally sintered at high temperatures. Two essential methods are known for the production of precise intermediate products, which are also referred to as compacts, blanks or green compacts. One method relates to the primary production by means of injection molding. Another approach concerns the production of compacts using presses. The present disclosure is primarily concerned with the pressing of hard metal powder at high pressures for the production of compacts for the powder-metallurgical production of cutting tools or the like.

The WO 2015/120496 A1 describes a molding tool for the powder-metallurgical production of a green compact, with an upper punch and a lower punch, which can be moved along a common pressing axis, a die body with a filling shaft for receiving powder material, the die body having an upper region in which the upper punch in the filling shaft along the Press axis is movably guided, and has a lower area in which the lower punch is movably guided in the filling shaft along the press axis, and with at least two cross slides, which form a molding area which determines the lateral outer contour of a green compact and which are arranged on the die body so as to be displaceable in a direction deviating from the pressing axis, the at least two cross slides only coming into contact with one another when the at least two cross slides are arranged in their respective end positions , wherein a cavity, which determines the shape of a pressed green body, is formed by the lower punches and upper punches arranged in their end positions and the at least two cross slides arranged in their end positions in a closed state of the molding tool, and wherein the at least two cross slides form a molding area, which determines the entire lateral outer contour of a green compact.

From the EP 2 933 041 A1 A method and a device for producing a green body are known, the device having a first stamp, a second stamp, a first female part and a second female part, the first stamp, the second stamp and the first female part interacting to shape the green body, wherein the second die part has an opening for receiving the second stamp, but does not form any surface of the green compact.

From the EP 2 933 043 A1 A method and a device for producing a green body for a cutting insert are known, the device having an upper die part, a lower die part, an upper punch and a lower punch, which work together to shape the green body, the die parts and the punches respectively are vertically movable.

From the US 2006/165828 A1 A device and a method for producing a green body for a cutting body is known, wherein a die is used which has two vertically displaceable mold halves, the two mold halves defining a common parting plane, furthermore two lateral pins are provided within the parting plane, one of which Form a horizontal recess in the green compact and are horizontally movable along the parting plane, the mold halves and the lateral pins jointly forming solid molded parts, and an upper punch and a lower punch being provided. The upper stamp interacts with the upper half of the mold. The lower stamp interacts with the lower half of the mold.

From the US 2015/037444 A1 a press is known for ultra-high pressure applications, i.e. for pressure ranges above 1 GPa. The press is used to manufacture workpieces from synthetic ultra-hard materials, such as synthetic diamonds, cubic boron nitride (cBN), polycrystalline diamonds, etc.

From the US 2013/039798 A1 A pressing tool for producing a green body for a cutting tool is known, the tool having a molded body and an upper molding plate covering the same, lateral slides, an upper stamp and a lower stamp, and lateral auxiliary stamps. The molded body, the molded plate and the side slides form solid molded parts. The upper stamp, the lower stamp and the auxiliary stamp are used to compress the material.

Tool geometries are known, the compacts of which cannot be produced in the course of the pressing process described above without extensive post-processing. Post-processing increases the manufacturing effort. The other way round, by means of known pressing processes for the production of green compacts, not all desired geometries and designs of hard metal compacts can be produced without post-processing or with little post-processing. Conversely, this means that the design of such tools takes into account the manufacturing conditions, so that compromises are made. This can limit the performance of the tools.

An example of a hard metal tool is a so-called indexable insert, in particular a so-called double cutter, which comprises two cutting edges or cutting edges. Two cutters are known which are designed to be point symmetrical. In other words, such a double cutter can have, for example, a base body with a longitudinal extension, a cutting edge being formed at a first end and at a second end facing away from the first end, the cutting edges being oriented in opposite directions with respect to a center of the base body. Such a design requires special measures in the production of the compacts. In particular, various design principles must be observed. The cavity in which the compact is formed is usually arranged in a certain way with respect to a main pressing axis. Presses for the production of hard metal compacts include Usually an upper punch and a lower punch, which can be moved towards one another along the main pressing axis in order to pressurize and compress a powder received in a cavity.

Furthermore, when designing matrices for the powder-metallurgical production of hard metal compacts, care is taken not to provide a mold division which runs over the cutting edges or transversely thereto. Nevertheless, the cutting edges are preferably in a main parting plane. This can lead to the fact that blanks of certain cutting tools cannot be produced without post-processing or with little post-processing by means of presses.

Another challenge in the design of press tools for the production of compacts for hard metal tools relates to the demolding of oblique, pointed chamfers or tangential transitions that open into the parting plane. This often leads to the fact that parts of the die or parts of the press which reproduce the shape of the compact have to be made at least in sections very thin-walled or pointed. This increases wear and the risk of breakage and is therefore preferably avoided.

Tungsten carbide compacts are pressed at very high pressures, which can range from approximately 2000 to approximately 4000 bar (0.2 to 0.4 GPa). The pressing of hard metal powders cannot easily be compared or even equated with the pressing of metal powder or other powdery materials. One reason for this is the so-called spring behavior of pressed hard metal compacts. In contrast to pellets based on metal powder, these consist to a considerable extent of plasticizers (e.g. paraffins, waxes) and are porous, i.e. they have air pockets or cavities. The spring-back behavior can, for example, be reflected in an increase in volume after pressing, which can amount to approximately 3% of the initial volume.

Pressing devices for hard metal pressing usually have no further ones besides the main punches which are assigned to the main pressing axis Stamp on. As already described above, the main stamps are usually an upper stamp and a lower stamp, which can be moved vertically and in particular can be moved towards one another in order to produce the compact.

In the field of tungsten carbide powder metallurgy, these main punches cannot simply be supplemented by further (lateral) punches, which are roughly similar to lateral slides in injection molding, but act as punches. On the one hand, this is due to the high pressures during the pressing process. Such (lateral) punches would also have a negative impact on the compact density distribution of the compact. In the context of this disclosure, the press density distribution is also referred to as the press microstructure distribution

The above restriction does not exclude the occasional use of secondary stamps or auxiliary stamps which are moved along a plane which is inclined with respect to the vertical. However, auxiliary stamps of this type are usually only used to produce subordinate contours, such as openings, lateral depressions or the like. The effective area with which such an auxiliary stamp acts on the compact is usually significantly smaller than the area of the respective side of the die wall which surrounds the compact.

In order to produce a component structure that is as favorable as possible, in particular a sufficiently homogeneous pressing density, the aim is usually to dimension the main punches in such a way that, viewed in the vertical direction, they cover the silhouette or the outline of the compact as completely as possible. If this were not the case, if a main stamp were significantly smaller than the silhouette of the compact, this would lead to unfavorable stress profiles or pressure profiles during pressing, since the entire cross section of the compact would not be directly exposed to the (primarily) pressing pressure generated by the main stamp.

Apart from the punches, a die for pressing blanks for the production of hard metal cutting tools usually has other molded parts, but these are not active (as a driven punch) during the pressing process involved. Such molded parts can basically be movable and are then referred to as sliders. However, solid molded parts are also conceivable. In general, the molded parts themselves are not moved during the pressing process. Movable molded parts, such as slides or the like, are moved for the demolding process in order to form the compact.

Against this background, the present disclosure is based on the object of specifying a method and a device for the near-net-shape production of hard metal compacts, in particular for the production of sintered blanks for cutting tools, which have a high degree of design freedom with regard to the tool geometry and a production with a favorable press structure or with allow favorable density profile. In particular, the production of hard metal compacts with point-symmetrical design is to be simplified. This applies in particular to compacts for cutting tools that have cutting edges that are oriented in opposite directions and face away from one another. Furthermore, if possible, a production of hard metal compacts for cutting tools is to be described which allows the production of cutting edges which are not impaired, in particular crossed, by shape division or burrs. Finally, a method and a device are to be specified which allow the use of particularly robustly designed stamps and preferably also molded parts which in particular do not comprise excessively thin and pointed shape sections.

• Bereitstellung einer mehrteiligen Matrize, umfassend:
  • Zuführen zumindest eines Frontalformteils, das in einer ersten Ebene, insbesondere einer Horizontalebene, verfahrbar ist, umfassend ein Zuführen eines ersten Frontalformteils und eines zweiten Frontalformteils,
  • Zuführen zumindest eines Querformteils, das in einer zweiten Ebene, insbesondere in einer Vertikalebene, verfahrbar ist, umfassend ein Zuführen eines oberen Querformteils und eines unteren Querformteils,
  • Bereitstellung einer Arretiereinrichtung zur Fixierung der Querformteile und Frontalformteile in der geschlossenen Stellung, um eine Umfangskontur des Presslings auszubilden,
  • Arretieren des zumindest einen Frontalformteils und des zumindest einen Querformteils mit der Arretiereinrichtung, um eine Kavität für einen Pressling zu definieren,
    • wobei Zuführrichtungen des zumindest einen Frontalformteils und des zumindest einen Querformteils schräg zueinander orientiert sind, vorzugsweise senkrecht zueinander,
    • wobei das zumindest eine Frontalformteil und das zumindest eine Querformteil Flächen des Presslings definieren, und
    • wobei die sich ergebende Kavität zumindest eine Öffnung aufweist, durch die ein Stempel einführbar ist,
• Zuführen eines Füllschuhs über eine Öffnung der Kavität und Befüllen der Kavität mit einem Hartmetallpulver, und
• Verdichten des Pulvers mit zumindest einem Stempel, der parallel zu einer Hauptpressrichtung verfahrbar ist, umfassend Zuführen eines Oberstempels und eines Unterstempels,
  wobei das Zuführen des zumindest einen Querformteils entlang einer Zuführrichtung erfolgt, die parallel zur Hauptpressrichtung ist.

The method is achieved by a method for the near-net-shape production of hard metal compacts, in particular for the production of sintered blanks for cutting tools, the method comprising the following steps:

• Providing a multi-part die comprising:
  • Feeding at least one frontal molded part, which can be moved in a first plane, in particular a horizontal plane, comprising feeding a first frontal molded part and a second frontal molded part,
  • Feeding at least one transverse molded part, which can be moved in a second plane, in particular in a vertical plane, comprising feeding an upper transverse molded part and a lower transverse molded part,
  • Provision of a locking device for fixing the transverse molded parts and front molded parts in the closed position in order to form a peripheral contour of the compact,
  • Locking the at least one front molded part and the at least one transverse molded part with the locking device in order to define a cavity for a compact,
    • feed directions of the at least one frontal molded part and the at least one transverse molded part are oriented obliquely to one another, preferably perpendicularly to one another,
    • wherein the at least one frontal molded part and the at least one transverse molded part define surfaces of the compact, and
    • wherein the resulting cavity has at least one opening through which a stamp can be inserted,
• Feeding a filling shoe through an opening of the cavity and filling the cavity with a hard metal powder, and
• Compacting the powder with at least one punch, which can be moved parallel to a main pressing direction, comprising feeding an upper punch and a lower punch,
  wherein the at least one transverse molded part is fed along a feed direction that is parallel to the main pressing direction.

The object of the invention is completely achieved in this way.

According to the invention, the feed axis of the at least one transverse molded part is oriented parallel to the main press axis, ie to the feed axis of the at least one punch. Nonetheless, the at least one transverse shaped part serves predominantly to shape a lateral section of the compact. The at least one stamp is used to shape at least one upper or lower section of the compact. The feed direction of the transverse molded part allows in particular the demolding of geometries that cannot be produced with molded parts that demold purely to the side (along the horizontal plane). In this way, the total number of parts required to form the die can be limited. Nevertheless, great freedom of design is guaranteed.

The first level and the second level are, for example, the horizontal level and the vertical level. However, this is not to be understood as restrictive. In general, the first plane and the second plane can be understood as planes oriented obliquely to one another, in particular as planes oriented perpendicular to one another.

Compacts can be produced which have outer surfaces which are slightly inclined to the main pressing direction and / or have radii that run out tangentially. In addition, undercut contours can be removed from the mold, which cannot be easily removed in a different manner without post-processing. For example, in certain embodiments of indexable inserts with two cutting edges oriented in opposite directions, a burr course transverse to the cutting edge of the cutting tool can be avoided.

The feeding of the at least one frontal molded part and the at least one transverse molded part can in particular comprise retracting or transferring the molded parts into a closed position. The locking can in particular include locking, fixing, generally holding the molded parts firmly in the closed position. In this way it is clarified that the at least one frontal molded part and the at least one transverse molded part are not stamps.

It goes without saying that the term near-net-shape production does not preclude the compacts from shrinking during a subsequent sintering process because the particles continue to compact or because binders and the like are removed.

The method is particularly suitable for the production of hard metal compacts for cutting inserts with little or no post processing. In the context of this disclosure, low-post-processing or post-processing should be understood to mean that no complex grinding processes or other material-removing processing processes are required in which considerable amounts of the material are removed. Nevertheless, the term post-processing or post-processing does not preclude the processing of a cutting edge that has already been formed. Furthermore, this does not rule out that burrs and the like are removed.

In an exemplary embodiment of the method, the at least one frontal molded part is fed laterally, the at least one frontal molded part having a frontal shaping section which defines a lateral section of the shape of the compact, and wherein the at least one transverse shaped part is fed vertically and has a lateral shaping section which has one further lateral section of the shape of the compact is defined.

Accordingly, the at least one frontal molded part can be referred to as a side slide. According to the above configuration, the at least one transverse molded part is also fed vertically, that is to say from above or from below. Nevertheless, a lateral shaping section is provided which does not primarily define an upper or a lower section of the shape of the compact. In other words, a frontal section of the at least one transverse molded part does not have a shaping section for the compact.

In the context of this disclosure, a frontal shaping section of a molded part is a section or surface that extends substantially perpendicular to the feed direction. In contrast, a lateral shaping section is oriented approximately parallel to the feed direction. Deviations are conceivable, especially for the formation of non-straight contours of the compact. With the at least one transverse molded part, there is therefore a separation of the feed direction and (main) orientation of the shaping section. In other words, when locking the at least one transverse molded part, it should be noted that simply locking in the feed direction is not sufficient. Rather are to take other measures to withstand the pressing pressure, which also acts transversely or at least obliquely to the feed direction on the transverse molded part.

According to a further exemplary embodiment, the at least one punch is fed vertically, the at least one punch having a frontal shaping section which defines a section of the shape of the compact, the shaping section of the punch preferably being designed to be unbreakable, and in particular blunt depressions for forming corresponding elevations of the Has pellets. According to this embodiment, thin-walled or even pointed sections can be dispensed with in the shaping section of the stamp. Nevertheless, compacts with tapers, bevels, radii or tangential transitions can be created.

According to a further exemplary embodiment, the step of providing a multi-part die comprises supplying an upper transverse molded part and a lower transverse molded part, the step of compacting comprising supplying an upper stamp and a lower stamp, the upper stamp and the upper transverse molded part of a first side, in particular one Upper side, are assigned, the lower punch and the lower transverse molded part being assigned to a second side, in particular an upper side, the upper stamp and the upper transverse shaped part being fed at least in sections via common guide elements, and the lower punch and the lower transverse molded part being at least in sections via common Guide elements are fed.

It is particularly advantageous if the punches and the cross-shaped parts use the same guide elements or support one another. This is possible because the corresponding feed directions are oriented parallel to one another.

In preparation for a pressing process, the cavity is usually first formed by moving the mold parts involved (still without the punches) from an open position to a closed position. In the closed position, the molded parts are fixed or locked. Accordingly, the cross-shaped parts provide a guide for the stamps. Overall, possible space problems in the upper area and in the lower area of the die can be avoided in this way. This applies in particular with regard to the fact that the upper stamp and the lower stamp cover the entire upper and lower silhouette of the compact as far as possible. This allows an inexpensive press structure.

According to a further exemplary embodiment, the upper punch and the lower transverse shaped part jointly define a first cutting edge, the lower punch and the upper transverse shaped part jointly defining a second cutting edge.

In this way, both the first cutting edge and the second cutting edge, which are assigned to a first and a second cutting edge, can be arranged in the (main) parting plane. Burrs and shape divisions across the cutting edge can be avoided. The upper punch accordingly interacts with the lower transverse molded part. The lower stamp interacts with the upper cross-shaped part. Accordingly, the shaping sections of the transverse shaped parts not only form lateral contours of the cavity, but at least in sections also form an upper region or a lower region. The upper punch contacts the lower cross-shaped part during pressing. The lower punch contacts the upper cross-shaped part during pressing. That is, in the area in which the respective transverse shaped parts are formed, the upper punch and the lower punch do not act directly against one another or do not overlap.

According to a further exemplary embodiment, the first cutting edge is assigned a first rake face and a first free face, the second cutting edge being assigned a second rake face and a second free face, and the first rake face by the upper punch, the second rake face by the lower punch, the first Free space is formed by the lower cross-shaped part, and the second open area is formed by the upper cross-shaped part.

In this way, for example, an indexable insert can be produced in the manner of a double cutter, in particular an indexable insert with a point-symmetrical design.

According to a further exemplary embodiment, after the powder has been compacted, a demolding step follows, comprising opening the multi-part die, extending the at least one front molded part, extending the at least one transverse molded part, and extending the at least one punch, the at least one transverse molded part parallel to the Main pressing direction is moved in order to release laterally non-demouldable lateral contours of the compact in the opposite configuration of the die.

This design is advantageous, for example, for tools for gloss turning or similarly designed cutting tools that have circular or circular-section-shaped cutting edges that have a diameter that is larger than a width of a base body of the cutting insert. Such a cutting plate is approximately bone-like. A central region of the "bone" can accordingly be shaped by corresponding frontal molded parts, the ends of the "bone" being removed from the mold by the upper punch and the lower transverse molded part as well as by the lower punch and the upper transverse molded part. In this way, cutting edges facing away from one another and oriented in opposite directions to one another can also be formed.

According to a further exemplary embodiment, the step of feeding a filling shoe comprises feeding the filling shoe laterally to an upper opening of the cavity, the filling shoe being guided over a free space which is provided by the upper punch which is spaced apart from the cavity.

The cavity is usually filled with the powder using gravity. For this purpose, the filling shoe is fed in laterally and, for example, brought over the opening of the cavity into which the upper punch penetrates during the pressing process. Accordingly, the upper punch is extended when filling. Preferably the upper cross-shaped part is designed in such a way that the filling shoe has enough space to fill the cavity. Accordingly, the guidance provided indirectly or directly by the upper cross-shaped part for the upper punch permits a corresponding disengagement movement of the upper punch.

• Herstellung eines Presslings gemäß einer Ausgestaltung des hierin beschriebenen Verfahrens,
• nachbearbeitungsarmes oder nachbearbeitungsfreies Teile-Handling, insbesondere Transfer von einer Pressanlage zu einer Sinteranlage, und
• Sintern der Presslinge.

The disclosure also relates to a method for producing hard metal cutting tools, in particular cutting inserts, comprising:

• Production of a compact according to an embodiment of the method described herein,
• Low-post-processing or post-processing-free parts handling, in particular transfer from a press system to a sintering system, and
• Sintering the compacts.

Parts handling is to be understood in particular to mean parts handling which, for example, involves moving the compacts from the pressing device to a sintering device. If necessary, temporary storage can take place in between. Nevertheless, defined processing steps can also be carried out on the compact, such as. B. automated deburring. Deburring can be done, for example, by brushing or blowing and usually affects unpressed components on the compact.

The object of the invention is achieved by a device for the near-net-shape production of hard metal compacts, in particular for the production of sintered blanks for cutting tools, with a bed, a multi-part die for forming a cavity, the at least one frontal molded part, which is in a first plane, in particular a horizontal plane, is movable, and has at least one transverse molded part, which is movable in a second plane, in particular in a vertical plane, wherein the at least one front molded part and the at least one transverse molded part are assigned guides which are oriented obliquely or at an angle to one another, preferably perpendicular to one another, the at least one frontal molded part and the at least one transverse molded part between an open position and a closed position are movable, wherein the at least one frontal molded part and the at least one transverse molded part define surfaces of the compact in the closed position, and wherein the resulting cavity has at least one opening through which a stamp of a stamp unit can be inserted, the device further comprising a filling unit and a stamp unit The filling unit has a filling shoe which can be fed to an opening of the cavity in order to fill the cavity with a hard metal powder, the stamping unit having at least one stamp which can be moved along a main pressing direction to compress the powder, the at least one transverse molded part can be fed along a feed axis which is parallel to the main pressing direction, the stamp unit having an upper stamp and a lower stamp, the die having an upper transverse molded part and a lower transverse molded part as well as a first frontal molded part and a second frontal molded part eist, and wherein a locking device is provided which fixes the transverse molded parts and front molded parts in the closed position to form a peripheral contour of the compact.

In this way too, the object of the invention is completely achieved.

The at least one front molded part and the at least one transverse molded part are slide-shaped parts of the die. These are not stamps. The horizontal plane is also referred to below by way of example as the X-Y plane, with reference to a coordinate system that is still to be defined. Accordingly, a Z direction is also provided, which defines a vertical direction that is parallel to the main pressing direction. Each plane that is parallel to the vertical direction or congruent with the vertical direction is referred to as a vertical plane in the context of this disclosure.

The at least one front molded part and the at least one transverse molded part in particular essentially define lateral surfaces or lateral sections of the compact.

According to a further exemplary embodiment, the device comprises at least two frontal shaped parts, the shaping sections of which face one another are and which can be moved between an open position and a closed position, at least two transverse shaped parts, the shaping sections of which face each other and which can be moved between an open position and a closed position, and at least two punches, the shaping sections of which face one another and which lie between one open position and a closed position are movable.

According to a further embodiment, the device comprises exactly two stamps, namely an upper stamp and a lower stamp, and exactly two transverse molded parts, namely an upper transverse molded part and a lower transverse molded part. By way of example, exactly two frontal molded parts can also be provided. These can be referred to as the front molded part and the rear molded front part.

Designs are conceivable in which all of the die parts forming the compact are designed as movable molded parts. Nevertheless, designs are also conceivable in which at least a section of the cavity is designed as a fixed molded part.

According to a further exemplary embodiment, the at least one frontal molded part can be fed in laterally and is provided with a frontal shaping section which defines a section of the shape of the compact, the at least one transverse shaped part having a lateral shaping section which defines a further section of the shape of the compact.

According to a further exemplary embodiment, the at least one stamp has a frontal shaping section which defines a further section of the shape of the compact. The shaping section of the stamp is preferably designed to be insensitive to breakage. The shaping section preferably has blunt depressions (or elevations) for forming corresponding elevations (or depressions) of the compact.

According to a further exemplary embodiment, at least one stamp of the stamp unit and at least one transverse molded part of the die are guided parallel to one another. According to an exemplary embodiment, at least one stamp of the stamp unit and at least one transverse molded part of the die use the same guide elements at least in sections.

According to a further exemplary embodiment, the upper transverse molded part provides a guide section for the upper punch. Likewise, the lower transverse molded part provides a guide section for the lower punch as an example. The upper punch and the upper transverse shaped part and the lower stamp and the lower transverse shaped part can also be coupled to one another indirectly via a common guide.

According to a further exemplary embodiment, the stamp unit has an upper stamp and a lower stamp, the die having an upper transverse molded part and a lower transverse molded part, the upper stamp and the upper transverse molded part using at least sections of the same guide elements, and the lower stamp and the lower transverse molded part being at least in sections use the same management elements.

According to a further exemplary embodiment, the upper punch and the lower transverse shaped part jointly define a first cutting edge of the compact and the lower punch and the upper transverse shaped part jointly define a second cutting edge of the compact.

According to a further exemplary embodiment, the first cutting edge is assigned a first rake face and a first free surface of the compact, the second cutting edge being assigned a second rake face and a second free surface of the compact, the first rake face being the upper punch, the second rake face being the lower punch , The first open area is formed by the lower transverse shaped part, and the second open area is formed by the upper transverse shaped part.

The device further comprises a locking device which fixes the transverse molded parts and the front molded parts in the closed position in order to form a peripheral contour of the compact. The locking device is preferably approximately ring-shaped. In other words, the locking device can laterally enclose the transverse molded parts and the frontal molded parts in order to secure them in the closed position.

The cavity is locked by the locking device in order to withstand the high pressing pressures. The locking device can bring about a non-positive and / or positive locking. The locking device can fix the transverse molded parts and the front molded parts relative to one another and / or relative to the bed of the device. The closed locking device can also be referred to as a closed locking device. For example, the locking device is a mechanically effective holding device.

The upper cross-shaped part preferably also contributes to sufficient space being available for the filling shoe. In particular, the upper transverse molded part can provide a guide or can be coupled to a guide that is also used by the upper punch. Furthermore, the upper transverse molded part is designed such that the filling shoe can reach the opening of the cavity. This can be done, for example, by means of corresponding cutouts in the transverse molded part.

According to a further aspect, the disclosure relates to a hard metal compact, in particular a compact for a turning tool that is produced with little or no post-processing, with at least one cutting edge, which is defined by a parting plane of a multi-part die, with a press structure or press density profile defined by a main press axis, which is a position conditioned in the die, comprising a design that is not only demouldable from the side, in particular due to the arrangement of the at least one cutting edge, at least one lateral section of the compact, in particular a free-area section inclined or curved with respect to the main pressing axis, being formed by a lateral shaping section of a transverse molded part, whose direction of movement in the die is oriented parallel to the main pressing axis, at least one lateral section of the compact being formed by a frontal shaping section of a front Is molded part is formed, the direction of movement in the die is oriented perpendicular to the main pressing axis. Such a compact can be manufactured according to an embodiment of the method described here. The compact is preferably produced in an embodiment of the device described here.

The compact is, in particular, a hard metal cutting insert which has two cutting edges which are symmetrical, in particular point symmetrical, with one another. The compact preferably does not have any burrs caused by the die of the pressing device, which cross the cutting edges of the cutting edges.

If a cutting tool is produced on the basis of the compact or poorly processed compact, it can be seen whether it is manufactured according to an embodiment of the method described here and / or in an embodiment of the device described here. In particular ridges, The course of the parting plane and the other design, including areas that cannot easily be demolded by means of (side) sliders, allow a corresponding conclusion.

In particular, the compact can be produced with little or no post-processing: cutting edges, tangential transitions, chip recesses, open spaces or clearance angles, tapering, curved or circular cutting edges that have an extension that makes lateral removal difficult, or the like.

The disclosure is not limited to such cutting inserts, in particular not exclusively to the two-cutters described above with two oppositely arranged, oppositely oriented cutting edges. However, reference is made to this type of cutting insert for purposes of illustration.

It goes without saying that the features of the disclosure mentioned above and those yet to be explained below can be used not only in the combination specified in each case, but also in other combinations or on their own without departing from the scope of the present invention.

Fig. 1

eine perspektivische Ansicht eines Hartmetall-Schneidwerkzeugs, welches gemäß zumindest einigen Aspekten der vorliegenden Offenbarung herstellbar ist;

Fig. 2

eine Seitenansicht der Ausgestaltung gemäß Fig. 1;

Fig. 3

eine frontale Ansicht der Ausgestaltung gemäß Fig. 1;

Fig. 4

eine Draufsicht der Ausgestaltung gemäß Fig. 1;

Fig. 5

eine schematische perspektivische Darstellung einer Pressvorrichtung für Hartmetallpresslinge, in einem explodierten Zustand;

Fig. 6

eine weitere Darstellung der Anordnung gemäß Fig. 5 in einer Füllkonfiguration;

Fig. 7

eine weitere Darstellung der Ausgestaltung gemäß Fig. 6, wobei ein Füllschuh über einer Öffnung einer Kavität platziert ist;

Fig. 8

eine weitere Ansicht der Ausgestaltung gemäß den Fig. 5 bis 7, wobei eine Matrize geschlossen ist und Stempel zum Pressen eingefahren sind;

Fig. 9

eine perspektivische Schnittansicht der Anordnung gemäß Fig. 8, wobei Stempel der Vorrichtung und der erzeugte Pressling aus Veranschaulichungsgründen nicht geschnitten sind, und wobei die Stempel und Formteile der Vorrichtung zur besseren Darstellbarkeit leicht ausgefahren sind;

Fig. 10

eine weitere Schnittansicht der Ausgestaltung gemäß den Fig. 8 und 9 in einer von der Darstellung gemäß Fig. 9 abweichenden Orientierung;

Fig. 11

eine Detailansicht der Darstellung gemäß Fig. 10 zur Veranschaulichung der Kavität;

Fig. 12

eine an die Darstellung gemäß Fig. 9 angelehnte Schnittdarstellung einer weiteren Ausführungsform einer Vorrichtung zur Herstellung eines Presslings;

Fig. 13

eine Detaildarstellung der Ausgestaltung gemäß Fig. 12 zur Veranschaulichung einer Kavität, wobei in Fig. 13 der Pressling aus Veranschaulichungsgründen nicht gezeigt ist; und

Fig. 14

eine schematische, stark vereinfachte, teilweise geschnittene Draufsicht auf eine Ausführungsform einer Vorrichtung zur Herstellung von Presslingen, zur Veranschaulichung einer Arretiereinrichtung.

Further features and advantages result from the following description of several preferred exemplary embodiments with reference to the drawings. Show it:

Fig. 1

3 is a perspective view of a hard metal cutting tool that can be manufactured in accordance with at least some aspects of the present disclosure;

Fig. 2

a side view of the configuration according to Fig. 1 ;

Fig. 3

a frontal view of the design according Fig. 1 ;

Fig. 4

a plan view of the configuration according to Fig. 1 ;

Fig. 5

a schematic perspective view of a pressing device for hard metal compacts, in an exploded state;

Fig. 6

a further representation of the arrangement according Fig. 5 in a filling configuration;

Fig. 7

a further representation of the design according to Fig. 6 , wherein a filling shoe is placed over an opening of a cavity;

Fig. 8

another view of the design according to the 5 to 7 , with a die closed and punches retracted for pressing;

Fig. 9

a perspective sectional view of the arrangement according Fig. 8 , wherein the stamp of the device and the pellet produced are not cut for reasons of illustration, and wherein the stamp and molded parts of the device are slightly extended for better representation;

Fig. 10

a further sectional view of the configuration according to the 8 and 9 in a from the representation Fig. 9 different orientation;

Fig. 11

a detailed view of the representation according Fig. 10 to illustrate the cavity;

Fig. 12

one according to the representation Fig. 9 based on a sectional view of a further embodiment of a device for producing a compact;

Fig. 13

a detailed representation of the design according Fig. 12 to illustrate a cavity, wherein in Fig. 13 the compact is not shown for purposes of illustration; and

Fig. 14

is a schematic, greatly simplified, partially sectioned plan view of an embodiment of an apparatus for the production of compacts, to illustrate a locking device.

With reference to the 1, 2, 3 and 4 An exemplary embodiment of a compact 10 is illustrated, which can be used for the powder-metallurgical production of a hard metal tool, in particular a cutting insert. The compact 10 is post-processing or low-post processing Powder presses can be generated. However, this requires a specific design of a device or a specific method for producing the compact.

The compact 10 primarily serves as an illustrative example for a large variety and variety of further compact, the production of which can take place in accordance with the aspects described herein which relate to the device and / or the method.

At least in principle, the compact 10 can also be designed by means of alternative methods and devices, for example by means of injection molding or alternative pressing methods for producing blanks. Nevertheless, these alternative approaches each have specific disadvantages that are at least partially overcome within the scope of the present disclosure. If an at least similar compact is produced using conventional pressing methods, post-processing is essential. Usually a raw contour is obtained by pressing or injection molding, which has to be processed extensively, in particular by grinding.

According to at least some embodiments, the method and the device according to the present disclosure allow a significant reduction or even elimination of such post-processing by means of grinding. In other words, near-net-shape and low-post-processing or post-processing can be produced.

In summary, the 3 and 4 a Cartesian coordinate system X, Y, Z are taken, which is used for illustration. An X axis denotes a longitudinal axis. A Y axis denotes a transverse axis. A Z axis denotes a height axis. It is understood that other assignments and designations can be used. The person skilled in the art can easily understand the necessary mental transformations and assignments. The same applies to position and direction information such as top, bottom, side, cross, front, back and Like. The coordinate system X, Y, Z is repeatedly referred to below for the purposes of illustration.

The compact 10 comprises a main body 12 which extends essentially in a longitudinal direction X, cf. also 3 and 4 . At the respective end of the main body 12, a cutting edge 18 is formed which defines a cutting edge 16. The cutting edge 18 is, for example, a cutting edge 18 which is at least partially circular in shape. Tools with such cutting edges 18 can be used, for example, for gloss machining or for turning the gloss.

In particular, as shown Fig. 4 , which shows a plan view, it can be seen that the cutting edges 18 have a diameter or a transverse extent (in the Y direction) which is greater than a transverse extent of the main body 12. Accordingly, a taper or constriction 14 is formed between the ends provided with the cutting edges 18.

In a fundamentally known manner, the cutting edges 16 comprise, in addition to the cutting edges 18, a rake face 20 and a free face 22 which includes a taper. The cutting edges 16 are designed with point symmetry with respect to a center of the compact 10. This allows a simple change between the two cutting edges 16 by a 180 ° rotation of the cutting insert.

The compact 10 is preferably oriented in a cavity of a pressing device such that the Z axis coincides with a main pressing direction. Accordingly, special precautions have to be taken in order to be able to demold the compact 10 with the smallest possible number of molded parts and punches within the framework of production that is as close to the final contour as possible, with little or no post-processing.

According to the view orientation in Fig. 4 the main pressing axis Z is oriented perpendicular to the representation there. In other words, a stamp would be the one in Fig. 4 shown silhouette "see". Would you also try the open spaces 22 of the Demoulding cutting edges 16 with the dies which can be moved in the main pressing direction Z would lead to very thin walls in the dies.

A purely lateral demolding, in which approximately two slides are provided, which can be moved along the Y direction, would each slider approximately in Fig. 3 Show the contour or silhouette shown. However, this would lead to a shape division in the region of the respective outer ends (in the X direction) of the cutting edges 18 and thus to the formation of burrs. This is undesirable.

It is therefore proposed within the scope of the present disclosure to demold the compact 10 by an interaction of frontal molded parts and transverse molded parts.

In Fig. 3 an area is indicated by dashed lines denoted by 24, which can be demolded laterally in the transverse direction Y by corresponding slides. An approximately cuboidal or trapezoidal slider can extend between the lines 24. In the 1 and 3 further shape divisions 26, 28 are indicated. The shape division 28 essentially coincides with the cutting edges 18. The shape division 26 describes a transition between a side surface of the main body 12 and an elevation 36 on the respective upper and lower back 34 of the main body 12.

In Fig. 3 the mold partitions 24 and 26 delimit a surface 30 which can be demolded by a so-called frontal molded part. The surface 30 is essentially flat. A surface denoted by 32 identifies the area that can be demolded by a so-called transverse molded part. The surface 32 essentially coincides with the free surface 22. Accordingly, surface 32 includes a taper in the Z direction.

34 denotes a surface which is defined by the mold partitions 26, 28 and describes the area which can be removed from the mold by a stamp which can be moved in the main pressing direction Z. The surface 34 comprises approximately the rake surface 20 including the back-shaped elevation 36.

The back-shaped elevation 36 is obtuse or obtuse-angled in the Z direction. Accordingly, the elevation 36 can be shaped by the geometry of the stamp without significant, disadvantageous wall thickness reductions in the stamp.

In particular, on the basis of the shape divisions 24, 26, 28 and the course of the pressing density caused by the main pressing axis Z, at least in the raw state of the compact 10, a conclusion can be drawn as to the type of production and the design of a die used for production. In addition, the shape divisions 24, 26, 28 can also be used to draw conclusions about the type of production and the design of a die used for production, even when the workpiece is sintered.

With reference to the 5 to 11 Exemplary aspects and configurations of a device and a method for producing near-net-shape hard metal compacts are illustrated. The device is designated 40 in total. The device 40 can be part of a press system. In particular, the device 40 is designed, for example, to produce hard metal compacts based on hard metal powder, the shape of which is based on the shape of the 1 to 4 illustrated compact 10 is at least similar.

For reasons of illustration, the following figures show simplified representations of the compact 10 and of components of the device 40. The orientation of the compact 10 in the device 40 is illustrated by the coordinate system X, Y, Z, which is shown in at least some of the figures to be described below.

The device 40 is used in particular for processing hard metal powder to produce hard metal compacts for the powder metallurgical production of cutting inserts, cutting inserts etc.

The device comprises a bed 42, which can be part of a frame or at least coupled to it. Furthermore, a die 46 is provided, the one Cavity 48 forms, cf. also Fig. 6 . In Fig. 6 an (upper) opening of the cavity 48, which is designated by 50, is also illustrated.

The die 46 comprises a first frontal molded part 54 and a second frontal molded part 56, which are accommodated on the bed 42, for example offset in the transverse direction Y, from one another. Accordingly, the first frontal molded part 54 is received on a horizontal guide 58. The second frontal molded part 56 is received on a horizontal guide 60. The horizontal guides 58, 60 are designed approximately as profile guides.

Furthermore, the die 46 includes so-called transverse shaped parts 64, 66 5 to 11 The exemplary embodiment illustrated has a first transverse molded part 64 and a second transverse molded part 66. The first transverse molded part 64 is shown in FIG Fig. 5 assigned to a first side of the device 40, which can also be referred to as the upper side. The second transverse molded part 66 is assigned to a second side of the device 40, which can also be referred to as the underside. The transverse shaped parts 64, 66 are offset from one another in the vertical direction along the vertical axis Z.

A vertical guide 68 is provided for moving the first transverse shaped part 64. A vertical guide 70 is provided for moving the second transverse molded part 66. The transverse shaped parts 64, 66 are coupled to the bed 42 via the vertical guides 68, 70.

Together, the frontal molded parts 54, 56 and the transverse molded parts 64, 66 define parts of the die 46 that are not actively moved during the pressing process itself. The molded parts 54, 56, 64, 66 are opened for demolding the compact 10. Through openings 50 in the (closed) cavity 48, which is formed by the molded parts 54, 56, 64, 66, punches 74, 76 can move in for compression. In the based on the 5 to 11 illustrated embodiment of the device 40, the cavity 48 is formed exclusively by basically moving parts. However, this does not rule out that in other exemplary embodiments, shaping sections of the cavity 48 are formed by molded parts which are coupled to the bed 42 in a manner fixed to the frame.

The device 40 comprises stamps 74, 76 which are assigned to a stamp group or stamp unit 82. The first stamp 74 can also be referred to as an upper stamp. The second stamp 76 can also be referred to as a lower stamp. Accordingly, the first stamp 74 is assigned to an upper side of the device 40 or the die 46. The second stamp 76 is assigned to an underside of the device 40 or the die 46. In the case of hard metal pressing of sintered blanks, two punches 74, 76 are usually used, which are arranged opposite one another in the height direction or vertical direction Z and can be fed towards one another in order to compress and shape the hard metal powder received in the cavity 48.

A first vertical guide 78 is provided for the movement of the first stamp 74. A second vertical guide 80 is provided for moving the second stamp 76. The vertical guide 80 of the stamp 74 is, at least according to some exemplary embodiments, directly or indirectly coupled to the first transverse shaped part 64. The vertical guide 80 of the second stamp 76 is coupled, for example, directly or indirectly to the second transverse molded part 66.

The horizontal guides 58, 60 for the frontal molded parts 54, 56 comprise a guide profile 88, which can also be referred to as a guide base. A corresponding counter profile is formed on the frontal molded parts 54, 56.

The vertical guides 68, 70 for the transverse shaped parts 64, 66 likewise comprise a guide profile 90 which is formed on the bed 42. The transverse shaped parts 64, 66 can contact the guide profile 90 via a corresponding counter profile.

The vertical guides 78, 80 for the punches 74, 76 of the stamp unit 82 include, for example, guide profiles 92 and 94 5 to 11 Illustrated embodiment, the guide profiles 92, 94 of the vertical guides 78, 80 are not formed directly on the machine bed 42 or are fixedly coupled thereto. Instead, the guide profiles 92, 94 are indirect or direct assigned to the cross-shaped parts 64, 66 or coupled to them. In other words, the transverse shaped parts 64, 66 can ensure the guidance of the punches 74, 76 for the movement in the Z direction, or can at least be part of such a guidance. This is made possible in particular by the fact that the transverse shaped parts 64, 66 and the punches 74, 76 can be moved parallel to one another in the Z direction.

In Fig. 5 Feed directions or directions of movement of the molded parts 54, 56, 64, 66 and the stamp 74, 76 are indicated by double arrows. The feed direction of the frontal molded part 54 is designated 100. The feed direction of the frontal molded part 56 is designated 102. The feed direction of the transverse shaped part 64 is designated 104. The feed direction of the transverse shaped part 66 is designated by 106. The feed direction of the stamp 74 is designated 108. The feed direction of the stamp 76 is designated 110.

The frontal shaped parts 54, 56 can be fed along a horizontal plane which is defined by the axes X, Y. The transverse shaped parts 64, 66 can be fed along a vertical plane which is oriented parallel to the Z axis or coincides with the Z axis. In other words, the frontal molded parts 54, 56 can be fed laterally. The transverse shaped parts 64, 66 can be fed vertically (from above or from below). The punches 74, 76 can also be fed vertically (from above or from below). The first transverse shaped part 64 and the first punch 74 have parallel feed directions 104, 108. The second transverse molded part 66 and the second punch 76 have parallel feed directions 106, 110. The feed directions 104, 106, 108, 110 are parallel to each other. The feed directions 100, 102 are oriented parallel to one another and, for example, approximately perpendicular to the other feed directions 104, 106, 108, 110. If several frontal molded parts are used, there can be further (lateral) feed directions, which do not necessarily have to be parallel to all other (lateral) feed directions.

A frontal shaping section 116 is formed on the first frontal shaped part 54. A frontal shaping section 118 is formed on the second frontal shaped part 56. A lateral shaping section 120 is formed on the first transverse shaped part 64. A lateral shaping section 122 is located on the second transverse shaped part 66 educated. A frontal shaping section 124 is formed on the first stamp 74. A frontal shaping section 126 is formed on the second punch 76.

In the sense of this disclosure, a frontal shaping section is to be understood as a section of the respective molded part which defines the cavity 48 or the shape of the compact 10 to be produced and which extends essentially transversely or perpendicularly to the feed direction of the molded part used. In contrast, a lateral shaping section is to be understood as a section of the molded part which defines the cavity 48 or the shape of the compact 10 to be produced and which extends approximately parallel or slightly inclined to the respective feed direction of the molded part.

Together, the shaping sections 116, 118, 120, 122, 124, 126 define the shape of the compact 10 to be produced, which results from the design of the cavity 48. In order to illustrate the cavity 48, the detailed views in FIGS Fig. 11 and 13 referred.

The front molded parts 54, 56 can be fed laterally, cf. the feed directions 100, 102. The shaping sections 116, 118 of the frontal shaped parts 54, 56 form lateral sections of the cavity 48 and of the compact 10 to be molded. In particular, the lateral surface 30 of the compact 10 can be produced with the shaping sections 116, 118, cf. also the 1 to 4 .

The punches 74, 76 are also provided with "frontal" shaping sections 122, 124 with which the respective surface 34 (cf. 1 to 4 ) of the compact 10 is formed, which is exemplarily formed on the top and bottom of the compact 10 to be manufactured. Thus, the surfaces 30, 34 to be formed by the "frontal" shaping sections 116, 118 and 122, 124 are essentially perpendicular or at most only slightly inclined to the feed directions 100, 102 and 108, 110.

The transverse shaped parts 64, 66, which can be fed along the feed directions 104, 106, can behave significantly differently. The "lateral" shaping sections 120, 122 define sections or surfaces 32 of the compact to be formed 10. The surfaces 32 can also be regarded as lateral surfaces, since they extend essentially perpendicularly or slightly inclined to a horizontal plane which is formed by the axes X, Y. However, the feed directions 106, 108 of the punches 74, 76 are parallel to the Z axis. In other words, the transverse shaped parts 64, 66 are fed vertically, for example from above or from below, although they form “lateral” sections or surfaces 32 of the compact 10. The direction of feed and the direction of action of the shaping section are oriented approximately transversely to one another.

This allows the surfaces 32, which roughly define the free surfaces 22 of the cutting edges 16, to be demolded in the opposite direction. A lateral demolding (along the X direction) is not possible, since in this case the constriction 14 of the main body 12 represents an undercut area. A lateral demolding in the Y direction would be disadvantageous, since then a shape division transverse or perpendicular to the course of the cutting edge 18 would be required.

The interaction of the shaping sections 116, 118, 120, 122, 124 can be seen in particular in the enlarged illustration in FIG Fig. 11 can be removed, wherein the cavity 48 is not shown completely closed there, and the shaping section 122 of the transverse molded part 66 is not shown there due to the sectional illustration.

With reference to the 5 to 11 An exemplary manufacturing process for producing the compact 10 is illustrated. Starting from an open position, in which the front molded parts 54, 56, the transverse molded parts 64, 66 and the plungers 74, 76 are extended at least a little from a closed position, the cavity is at least partially closed, cf. in particular Fig. 6 .

Fig. 6 illustrates a fill configuration in which at least the front molded parts 54, 56 and the transverse molded parts 64, 66 are in the closed position. In other words, a cavity 48 is already defined, which can be filled with a hard metal powder. For this purpose, the device 40 has a filling unit 132, which comprises a filling shoe 134. The filling shoe 134 can preferably be fed to an upper side of the die 46 in order to fill the cavity 48, cf. also 6 and 7 . A feed direction of the filling shoe 134 is shown in FIG Fig. 7 designated 136. The filling shoe 134 can be fed along a horizontal plane which is defined by the X-axis and the Y-axis.

The filling shoe 134 is placed, for example, over the opening 50 through which the (upper) punch 74 can move. Accordingly, at least the stamp 74 of the stamp 182 is spaced apart from the die 46 in the filling configuration. This is in the 6 and 7 shown clearly.

The (upper) transverse molded part 64 also has a corresponding recess, so that the filling shoe 134 can be fed to the cavity 48. The cavity 48 is usually filled with the hard metal powder using gravity.

The stamp 74 is advantageously attached to a guide arm 138, in particular to its guide profile 92 (cf. Fig. 5 ) performed in order to create enough space for the filling shoe 134. The coupling of the guides of the stamp 74 and the transverse shaped part 64 creates the required accessibility for the filling shoe 134.

Likewise, a guide bracket 140 can also be formed in the (lower) transverse shaped part 66, on which the (lower) punch 76 is guided via a corresponding guide profile 92.

The further guide profiles 94 of the transverse shaped parts 64, 66 (cf. again Fig. 5 ) are arranged adjacent to the lateral shaping sections 120, 122.

Fig. 8 shows a closed pressing state in which the punches 74, 76 are also inserted into the die 46 in order to pressurize the hard metal powder located there. The punches 74, 76 are now each coupled both to the guide profile 92 on the guide arm 138, 140 and to the guide profile 94 which is adjacent to the shaping section 120, 122. Accordingly Precise guidance and force transmission take place in particular during the pressing process.

Fig. 9 illustrates in a partially sectioned representation a state after the actual pressing process in which the compact 10 is formed. In Fig. 9 For reasons of illustration, the compact 10 and the stamps 74, 76 are not shown in section. In the Fig. 9 The sectional plane shown runs centrally through the die 46 and parallel to the X-axis and the Z-axis. Furthermore, in Fig. 9 the molded parts 56, 64, 66 and the stamp 74, 76 partially disengaged. The compact 10, which is one of the design according to the 1 to 4 basically has a similar shape, can be removed from the mold or removed.

In Fig. 9 For reasons of illustration, the compact 10 and the stamps 74, 76 are not shown in section. In the Fig. 9 The cutting plane shown runs centrally through the die and parallel to the X axis and the Z axis.

Fig. 10 shows an analog perspective, partially sectioned illustration of the device 40 after the pressing process, the section plane in FIG Fig. 10 runs parallel to the Y axis and parallel to the Z axis. Again, the molded parts 54, 56, 64 and the punches 74, 76 are shown partially disengaged. Fig. 11 illustrates a detailed representation of the design according to Fig. 10 . The interaction of the shaping sections 116, 118, 120, 122, 124, 126 can be viewed together 9 to 11 be removed. In addition, the further sectional view according to Fig. 12 as well as the associated detailed representation according to Fig. 13 referred.

Fig. 12 shows a further perspective, partially sectioned illustration of a device designated by 40, the design of which is basically the design of the device based on FIG Fig. 9 device 40 shown is similar.

A further development can consist in forming stop surfaces 144, 146 on the bed 42, which can also be referred to as chamfers. From the sectional view in Fig. 12 it can be seen that corresponding to the transverse shaped parts 64, 66 Counter surfaces are formed. In this way, a highly precise positioning and alignment of the transverse shaped parts 64, 66 with respect to the bed 42 can result. This results in a highly precisely defined cavity.

In the additional detailed representation according to Fig. 13 For reasons of illustration, the compact 10 is not shown. Furthermore, in Fig. 13 the moldings 64, 66 and 56 shown in the closed position. The stamps 74, 76 are also shown in the retracted, closed position. In this way, the cavity 48 is illustrated, which represents a negative of the compact 10.

Fig. 14 shows a schematic, highly simplified, partially sectioned top view of a further embodiment of the device 40 Fig. 14 The sectional plane runs approximately parallel to the X-axis and to the Y-axis centrally through the cavity 48. Accordingly, the frontal shaped parts 54, 56 and the transverse shaped parts 64, 66 are shown in section.

Further illustrated Fig. 14 a locking device designated 150, which is designed to absorb lateral forces or pressures during the pressing process. In other words, the locking device 150 serves to fix or lock the front molded parts 54, 56 and the transverse molded parts 64, 66 in the closed position in order to form the cavity 48 with high precision.

For example, the locking device 150 can comprise at least one holder 152, 154. The locking device 150 can support and fix the molded parts 54, 56, 64, 66 in a positive, non-positive or other manner at least during the pressing process.

Claims (15)

1. A method for the near-net-shape manufacture of hard-metal pressed articles, in particular for the manufacture of sinter raw parts for cutting tools, comprising the following steps:

   - providing a multi-part die (46) comprising:

   - feeding at least one frontal mold part (54, 56) that is movable in a first plane, comprising feeding a first frontal mold part (54) and a second frontal mold part (56),

   - feeding at least one transverse mold part (64, 66) that is movable in a second plane, comprising feeding an upper transverse mold part (64) and a lower transverse mold part (66),

   - providing a locking device (150) for fixing the transverse mold parts (64, 66) and frontal mold parts (54, 56) in the closed position to form a circumferential contour of the pressed article (10),

   - locking the at least one frontal mold part (54, 56) and the at least one transverse mold part (64, 66) with the locking device (150) to define a cavity (48) for a pressed article (10),

   wherein feed directions of the at least one frontal mold part (54, 56) and the at least one transverse mold part (64, 66) are oriented inclined to one another,

   wherein the at least one frontal mold part (54, 56) and the at least one transverse mold part (64, 66) define surfaces (30, 32) of the pressed article (10), and

   wherein the resulting cavity (48) comprises at least one opening (50) through which a punch (74, 76) is insertable,

   - feeding a filling shoe (132) above an opening (50) in the cavity (48) and filling the cavity (48) with a hard-metal powder, and

   - compressing the powder with at least one punch (74, 76) that is movable parallel to a main pressing direction (Z), comprising feeding an upper punch (74) and a lower punch (76),
   wherein the at least one transverse mold part (64, 66) is fed along a feed direction (104, 106) that is parallel to the main pressing direction (Z).
2. The method according to claim 1, wherein the at least one frontal mold part (54, 56) is fed in a horizontal plane, wherein the at least one transverse mold part (64, 66) is fed in a vertical plane, and wherein the feed directions of the at least one frontal mold part (54, 56) and the at least one transverse mold part (64, 66) are oriented perpendicular to each other.
3. The method according to claim 1 or 2, wherein the at least one frontal mold part (54, 56) is fed laterally and provided with a frontal shaping portion (116, 118) defining a lateral portion (30) of the shape of the pressed article (10), and wherein the at least one transverse mold part (64, 66) is fed vertically and provided with a lateral shaping portion (120, 122) defining a further lateral portion (32) of the shape of the pressed article (10).
4. The method according to one of claims 1 to 3, wherein the at least one punch (74, 76) is fed vertically and provided with a frontal shaping portion (124, 126) that defines a portion (34) of the shape of the pressed article (10), wherein the shaping portion (124, 126) of the punch (74, 76) is preferably designed to be insensitive to breakage and in particular provided with blunt depressions for forming corresponding elevations (36) of the pressed article (10).
5. The method according to one of claims 1 to 4, wherein the upper punch (74) and the upper transverse mold part (64) are associated with a first side, in particular an upper side, wherein the lower punch (76) and the lower transverse mold part (66) are associated with a second side, in particular a lower side, wherein the upper punch (74) and the upper transverse mold part (64) are fed at least partially via common guide elements (92, 94), and wherein the lower punch (76) and the lower transverse mold part (66) are fed at least partially via common guide elements (92, 94).
6. The method according to claim 5, wherein the upper punch (74) and the lower transverse mold part (66) together define a first cutting edge (18), and wherein the lower punch (76) and the upper transverse mold part (64) together define a second cutting edge (18), and preferably wherein the first cutting edge (18) is associated with a first rake face (20) and a first relief face (22), wherein the second cutting edge (18) is associated with a second rake face (20) and a second relief face (22), and wherein the first rake face (20) is formed by the upper punch (74), the second rake face (20) by the lower punch (76), the first relief face (22) by the lower transverse mold part (66), and the second relief face (22) by the upper transverse mold part (64).
7. The method according to any one of claims 1 to 6, further comprising a demolding step after the step of compressing the powder, including opening the multi-part die (46), comprising extending the at least one frontal mold part (54, 56), extending the at least one transverse mold part (64, 66), and extending the at least one punch (74, 76), wherein the at least one transverse mold part (64, 66) is moved parallel to the main pressing direction (Z) to release lateral contours (32) of the pressed article (10) that cannot be demolded laterally in the given configuration of the die (46).
8. The method according to any one of claims 1 to 7, wherein the step of feeding a filling shoe (134) comprises laterally feeding the filling shoe (134) to an upper opening (50) of the cavity (48), wherein the filling shoe (134) is guided into a clearance space provided by the upper punch (74) that is spaced from the cavity (48).
9. A method for the manufacture of hard-metal cutting tools, in particular cutting inserts:

   - manufacturing a pressed article according to one of claims 1 to 8,

   - processing the article with little or no post-processing, in particular transfer from a pressing plant to a sintering plant, and

   - sintering of the pressed article.
10. A device (40) for the near-net-shape manufacture of pressed hard-metal parts (10), in particular for the manufacture of blanks to be sintered for cutting tools, comprising a bed (42), a multi-part die (46) for forming a cavity (48), which comprises at least one frontal mold part (54, 56) that is movable in a first plane, and at least one transverse mold part (64, 66) that is movable in a second plane, wherein guides (58, 60, 68, 70) are associated with the at least one frontal mold part (54, 56) and the at least one transverse mold part (64, 66), wherein the guides (58, 60, 68, 70) are oriented inclined to one another, wherein the at least one frontal mold part (54, 56) and the at least one transverse mold part (64, 66) are movable between an open position and a closed position, wherein the at least one frontal mold part (54, 56) and the at least one transverse mold part (64, 66) define in the closed position surfaces (30, 32) of the pressed article (10), and wherein the resulting cavity (48) comprises at least one opening (50) through which a punch (74, 76) of a punch unit (82) is insertable, wherein the device (40) further comprises a filling unit (132) and a punch unit (82), wherein the filling unit (132) comprises a filling shoe (134), which can be fed to an opening (50) in the cavity (48) to fill the cavity (48) with a hard-metal powder, wherein the punch unit (82) comprises at least one punch (74, 76) that is movable along a main pressing direction (Z) for compressing the powder, wherein the at least one transverse mold part (64, 66) can be fed along a feed axis (104, 106) that is parallel to the main pressing direction (Z), wherein the punch unit (82) comprises an upper punch (74) and a lower punch (76), and wherein the die comprises an upper transverse mold part (64) and a lower transverse mold part (66) as well as a first frontal mold part (54) and a second frontal mold part (56), characterized by a locking device (150) that fixes the transverse mold parts (64, 66) and frontal mold parts (54, 56) in the closed position to form a circumferential contour of the pressed article (10).
11. The device (40) according to claim 10, wherein the at least one frontal mold part (54, 56) is movable in a horizontal plane, wherein the at least one transverse mold part (64, 66) is movable in a vertical plane, and wherein the feed directions of the at least one frontal mold part (54, 56) and of the at least one transverse mold part (64, 66) are oriented perpendicular to one another.
12. The device (40) according to Claim 10 or 11, comprising at least two frontal mold parts (54, 56), whose shaping portions (116, 118) are facing each other and which are movable between an open position and a closed position, at least two transverse mold parts (64, 66), whose shaping portions (120, 122) are facing each other and which are movable between an open position and a closed position, and at least two punches (74, 76), whose shaping portions (124, 126) are facing each other and which are movable between an open position and a closed position, wherein at least one punch (74), in particular the upper punch, is spaced from the cavity (48) in a filling configuration in such a way that the filling shoe (134) can be fed, in particular laterally, to the opening (50) that is arranged for accommodating the punch (74), in order to fill the cavity (48).
13. The device (40) according to any one of claims 10 to 12, wherein the at least one frontal mold part (54, 56) is laterally feedable and provided with a frontal shaping portion (116, 118) that defines a portion (32) of the shape of the pressed article (10), and wherein said at least one transverse mold part (64, 66) is provided with a lateral shaping portion (124, 126) that defines a further portion (32) of the shape of the pressed article (10), and wherein the at least one punch (74, 76) comprises a frontal shaping portion (124, 126) defining a further portion (34) of the shape of the pressed article (10).
14. The device (40) according to any one of claims 10 to 13, wherein at least one punch (74, 76) of the punch unit (82) and at least one transverse mold part (64, 66) of the die (42) are guided parallel in relation to one another and are preferably using the same guide elements (92, 94), at least partially, preferably wherein the upper punch (74) and the upper transverse mold part (64) use at least partially the same guide elements (92, 94), and wherein the lower punch (76) and the lower transverse mold part (66) use at least partially the same guide elements (92, 94).
15. The device (40) according to any one of claims 10 to 14, wherein the upper punch (74) and the lower transverse mold part (66) together define a first cutting edge (18) and the lower punch (76) and the upper transverse mold part (64) together define a second cutting edge (18), preferably wherein a first rake face (20) and a first relief face (22) are associated with the first cutting edge (18), wherein a second rake face (20) and a second relief face (22) are associated with the second cutting edge (18), wherein the first rake face (20) is formed by the upper punch (74), the second rake face (20) by the lower punch (76), the first relief face (22) by the lower transverse mold part (66), and the second relief face (22) by the upper transverse mold part (64).

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