Method and apparatus for manufacturing hard metal stamping articles - Patents.com

Abstract

The method for producing a hard metal pressed article comprises the steps of providing a die forming a cavity for producing a pressed article having at least one cutting edge and at least one chip breaking groove associated with a chip space, the steps of providing a movable die part at least partially defining the shape of the pressed article having an operating surface, the die part being feedable in a first feed direction, and providing a movable die body having a rod-shaped operating part for producing a through hole, the rod-shaped operating part in particular having a front surface, the die body being feedable in a second feed direction. The first feed direction and the second feed direction are inclined at least 45° to each other. The method further comprises the steps of forming a pressed article from a hard metal powder introduced into the cavity and compressed in at least one main pressing direction, the steps of providing the die part and the die body and positioning the die body and its operating part in the cavity to bring the powder into intimate contact with the abutment area on the die part. The disclosure also relates to respective devices for producing hard metal pressed articles.

Description

[Technical field]

[0001] The disclosed invention relates to a method and a manufacturing device for producing hard metal pressed articles. The disclosure further relates to the production of green parts for sintering components made of hard metal, in particular cutting tools, including cutting inserts for turning, milling, drilling, etc., indexable inserts, etc. [Background technology]

[0002] From WO 2017 / 158122 a method and a manufacturing device are known for producing a hard metal pressed article. Methods and manufacturing devices for producing hard metal pressed articles for cutting tools comprising a central through hole are known from WO 2018 / 069397 and WO 2013 / 024473. The through hole is produced by two opposing die bodies with parallel feed directions.

[0003] Cutting tools made from hard metals are generally sintered at high temperatures. Various methods are known for producing precisely shaped intermediate bodies, also called pressed articles, green parts, or compacts. One method involves primary molding using injection molding. Another approach involves using extrusion to generate precise cross-sections, whereby these parts must be further processed to achieve the final tool shape. Another approach involves producing pressed articles by pressing. The present disclosure relates primarily to the pressing of hard metal powders at high pressure to produce pressed articles for powder metallurgical manufacturing, such as cutting tools.

[0004] In machining with cutting tools, the supply of coolants and lubricants is of great importance for productivity, tool life, and achievable accuracy. Coolants and lubricants reduce friction and help dissipate heat from the machined area (from the workpiece and the tool). Finally, coolants and lubricants can also remove chips and other debris from the machined area.

[0005] It is often desirable to introduce coolants and lubricants as close as possible to the machining site, so that, for example, lubricant consumption can be optimized, which is advantageous in terms of costs and potential environmental impacts.

[0006] For the delivery of coolants and lubricants at a desired location and with a desired direction and / or spray shape, established solutions exist, such as the so-called Loc-Line system from Lockwood Products Inc., Lake Oswego, OR, USA. This system comprises a flexible arm with an integrated fluid channel that is deformable in three dimensions and can be equipped with a nozzle.

[0007] However, such systems are not suitable for all types of applications and are not suitable for all types of tools. For example, in internal machining, such systems reach their limits. Another approach involves providing fluid channels directly in the tool. In this way, the coolant or lubricant can be brought very close to the machining site. Moreover, the coolant and lubricant can cool the cutting tool "from the inside".

[0008] As mentioned before, cutting tools cannot be manufactured with any degree of freedom: the materials used (such as hard metals) require specific manufacturing and forming processes.

[0009] Cutting inserts with integrated cooling channels are known, for example, from US 2002 / 0106250 A1. DE 10 2013 111 741 A1 discloses a machining tool with an integrated coolant circuit, in which a first channel for the supply and a second channel for the return of the coolant are provided.

[0010] The integration of lubricant / coolant channels in cutting tools is known. However, it has been found that for manufacturing reasons, design compromises are often necessary. Furthermore, the formation of lubricant / coolant channels is often associated with an additional manufacturing step and therefore with significant additional costs. Since the devices (tools) for producing pressed articles can be of any complexity, different boundary conditions also need to be taken into account in the design. Summary of the Invention [Problem to be solved by the invention]

[0011] Against this background, the object of the present disclosure is to provide a method and a manufacturing device for manufacturing a hard metal pressed article for manufacturing a cutting tool having at least one integrated through hole, the through hole being intended for use as a lubricant coolant channel, for example. The through hole should preferably be well positioned in the pressed article and the cutting tool manufactured thereon. The through hole should allow the most efficient supply of lubricant cooling fluid and similar substances. The manufacturing of the through hole should be able to be integrated into the pressing process for manufacturing the pressed article with as little or no additional effort as possible. The through hole should be able to be used in the finished cutting tool with little or no post-processing. [Means for solving the problem]

[0012] With regard to this method, this object is achieved by a method for manufacturing hard metal pressed articles, in particular for producing sintered raw parts for cutting tools, which comprises the following steps: Providing a die forming a cavity for producing a pressed article having at least one cutting edge and at least one chip breaking groove associated with a chip space, the process comprising: Providing a movable die part, in particular a punch or slider, which at least partially defines the shape of a press article having an operating surface, the die part being feedable in a first feed direction; providing a movable mold body having a rod-shaped operating part for forming a through hole, the rod-shaped operating part having a front surface in particular, the mold body being feedable in a second feed direction, the first feed direction and the second feed direction being inclined to each other at an angle of at least 45°; and forming a pressed article from hard metal powder introduced into the cavity and compressed in at least one main pressing direction, the process comprising: The process includes providing a mold part and a mold body, with the mold body positioned to closely contact the powder within the cavity with its operating portion at an abutment area on the mold part to form a through hole.

[0013] The objectives of the present disclosure are thus achieved.

[0014] With regard to the device, this object is achieved by an apparatus for producing hard metal pressed articles, in particular for producing sintered green parts for cutting tools, which apparatus comprises: A die forming a cavity for producing a pressed article having at least one cutting edge and at least one chip crushing groove associated with a chip space, the die comprising: at least one movable die part, in particular a punch or slider, which at least partially defines the shape of the press article having an operating surface and which can be fed in a first feed direction; a movable mold body having a rod-shaped operating part for forming a through hole, the rod-shaped operating part having a front surface in particular, and a mold body which can be fed in a second feed direction; the first feed direction and the second feed direction are inclined at an angle of at least 45° to each other; the cavity is filled with a hard metal powder; the device has at least one pressing direction for compressing the hard metal powder introduced into the cavity, The die parts and die body are movable, and the die body in the cavity having the operating portion is positioned to bring the powder into close contact with the abutment area on the first die part to form a through hole.

[0015] The objectives present in the present disclosure are thus achieved as well.

[0016] According to an exemplary embodiment, the apparatus is configured to carry out a method according to one of the aspects described herein. It is understood that the method and the apparatus according to the present disclosure can be similarly configured and further developed. This applies in particular to the exemplary embodiment described below, which can be applied both to the method according to the present disclosure and to the apparatus according to the present disclosure. The apparatus typically has a control unit (sequence control) for controlling the pressing process. In this way, procedural aspects and apparatus aspects can be combined.

[0017] According to another aspect, the present disclosure relates to a hard metal stamping article produced according to at least one embodiment of the method described herein.

[0018] The through-holes may also be called through-openings, through-bores or channels (with a closed cross-section). In the exemplary embodiment, the through-holes function as lubricant / coolant through-holes. In other words, the through-holes in the exemplary embodiment are intended to supply coolant and lubricant (lubricant fluid) to the target. The through-holes are in particular not open channels, troughs or grooves. The through-holes have at least partially closed cross-sections.

[0019] The method and device according to the present disclosure make it possible to integrate through-holes in the pressed article during the pressing step, in other words, the through-holes do not have to be created by machining in a subsequent processing step.

[0020] For example, providing a die part designed as a punch or slider and a further die body defining a through hole can be carried out in such a way that the die body and thus the through hole are suitably positioned relative to the cutting edge and the chip-crushing grooves of the pressed article.

[0021] The intimate positioning of the powder on the front surface of the operating portion, particularly the mold body, against the abutment areas of the mold parts allows the production of continuous holes without the need to remove the wall or "skin" remaining in front of the exit of the through hole.

[0022] The powder-tight contact of the operative part of the mold body in the contact area of ​​the mold part serves to form the through hole. In this way, the outlet of the through hole towards the mold part can be created. The powder-tight contact between the operative part of the mold body and the contact area of ​​the mold part occurs in the cavity. In other words, during compression, the hard metal powder surrounds the contact area of ​​the mold part and the mold body where the powder-tight contact takes place.

[0023] The feed directions of the die parts and the die body are inclined to each other by at least 45°. This includes inclination angles between 45° and 135°, and thus angles of 90° + / - 45°. That is, the feed directions of the die parts and the die body are inclined to each other at an obtuse angle. In an exemplary embodiment, the feed directions of the die parts and the die body are orthogonal to each other or substantially orthogonal (corresponding to an inclination angle of 90° and / or orthogonal to each other).

[0024] According to the above embodiment, there is no parallelism between the first feed direction and the second feed direction, so that the inclination between the feed directions of the mold parts and the mold body is at least 45°, excluding angles of 0°, 180° and multiples thereof.

[0025] Chip breaking grooves, which can also be called chip guide surfaces, are for example steps built into the back of the cutting edge of a cutting tool. Chip breaking grooves usually serve to guide and break the chips. Good chip removal increases work safety (avoiding long chips). They can also have a positive effect on the temperature conditions during processing.

[0026] In the context of the present disclosure, "powder intimate contact" means that the die body and die parts are in contact with each other with a very small gap remaining. The size of the remaining gap allowed is based on the size (e.g. average diameter, expected minimum diameter) of the hard metal powder used. It must be ensured that the powder particles or grains are prevented from penetrating into the gap between the die body and die parts. The remaining gap is adapted to the normal grain size and / or particle diameter of the hard metal powder used. For example, the hard metal powder is present in the form of compact granular particles (e.g. granular balls), the average diameter of which is usually about 50 μm (micrometers) to 500 μm (micrometers).

[0027] During the pressing process, these balls are divided into hard metal powders with smaller particle sizes, which however only flow freely to a limited extent, so that penetration into the gaps that "make the powder tight" is less likely to occur, and thus the desired throughput is guaranteed overall.

[0028] According to an exemplary embodiment, the positioning / contacting for tightly contacting the powder includes a gap of up to 15 μm (micrometers) between the operating portion of the mold body and the contact area of ​​the mold part. According to an exemplary embodiment, the positioning / contacting for tightly contacting the powder includes a gap of up to 10 μm (micrometers) between the operating portion of the mold body and the contact area of ​​the mold part. According to an exemplary embodiment, the positioning / contacting for tightly contacting the powder includes a gap of up to 5 μm (micrometers) between the operating portion of the mold body and the contact area of ​​the mold part.

[0029] In one embodiment, the method and apparatus of the present invention uses precisely controllable axes to position the mold parts and mold body on the die. By way of example, the positioning accuracy is + / - 1 μm (micrometer).

[0030] A feed operation generally involves positioning the die parts and die body in relation to forming the pressed article. This may include the actual compression step (pressing operation), but it may also involve operations not directly involved in compression (positioning operations, and sometimes even demolding).

[0031] According to an exemplary embodiment, the mold body is rod-shaped at least in its operating part. The form of the rod is adapted to the desired shape of the through hole. The mold body is configured, for example, as a slider for forming the through hole. The feed direction of the mold body defines the main extension direction of the through hole, at least in the exemplary embodiment. The operating part is configured, exemplarily, as a protrusion along the feed direction of the mold body, but a tapered shape is also conceivable.

[0032] In an exemplary embodiment, the inner contour of the through hole is determined primarily and exclusively by the configuration of the die body having, in particular, the operating portion, and the front surface of the pressed article in the area of ​​the outlet of the through hole facing the die part is defined by the die part.

[0033] In exemplary embodiments, the mold body has a length-to-diameter ratio, at least in its operative portion, of at least 3:1. In exemplary embodiments, the mold body has a length-to-diameter ratio, at least in its operative portion, of at least 5:1. In exemplary embodiments, the mold body has a length-to-diameter ratio, at least in its operative portion, of at least 8:1. According to these embodiments, at least the operative portion of the mold body is rod-shaped with a pronounced longitudinal extension.

[0034] For example, the mold body is formed in its operating part in a cylindrical shape with a substantially constant cross section along its longitudinal extension. Nevertheless, this may include a release taper or the like. It is also generally conceivable to configure the mold body in its operating part in a conical shape or to taper towards the abutment area. Such configurations are conceivable as long as the mold body is releasable. Thus, the mold body may generally also include a step (diameter jump), a shoulder, etc. The cross section of the mold body in the operating part may be configured, for example, as a circle, an ellipse, a polygon, a body of constant width, or similar. Depending on the loads occurring during the pressing process, a circular or an elliptical cross section may be suitable.

[0035] The die parts are designed, for example, as punches (punch parts) or sliders. The die parts are generally also called, in the context of this disclosure, mating parts, abutment parts or detent parts for the die body. In hard metal pressing, there may be no clear distinction between punches and sliders. Typically, the slider is the component that is not moved during the pressing process. The force required to press / compress the hard metal powder is mainly generated by one or more punches. However, it is not excluded that the component that primarily functions as the slider is moved, at least to a limited extent, during the pressing process. Conversely, it is not excluded that the punch is at least temporarily fixed (i.e., not moved) during the pressing process. However, despite this conceptual ambiguity, the division into slider and punch is familiar to those skilled in the art, and therefore within the scope of this disclosure, this division will be used to describe certain embodiments.

[0036] The edges or cutting edges of the pressed article lie at least partially in a regular manner on the main parting surface or on other die parting surfaces, which are for example defined by the punch and other (fixed or movable die parts).Depending on the main pressing direction (at least the punch or the main punch), therefore, constant boundary conditions regularly arise for the cutting edges and the paths of the chip-breaking grooves spatially connected to the cutting edges.

[0037] The cutting edges are typically oriented at a normal or obtuse angle to the main press direction, and according to the present disclosure, the feed direction of the die body and the feed direction of the die parts are also oriented at an obtuse angle (including perpendicular), so that the lubricant / coolant channels formed by the through holes can be conveniently located close to the chip-breaking grooves adjacent to the cutting edges.

[0038] The chip-breaking grooves, at least in certain embodiments, are exemplarily arranged as complex-shaped chip-breaking grooves, which may include, for example, chip troughs with curvatures (3D curvatures) on several sides, which may further include a combination of several cutting edges and, as a result, several chip-breaking grooves.

[0039] Powder-tight abutment of a mold body on a mold part includes flush abutment of the front surface of the mold body onto the abutment area of ​​the mold part. As an example, the front surface and the portion of the abutment area facing it are flat / planar. Matching contours / curvatures are also generally contemplated, as long as the necessary clearance for powder-tight abutment is maintained.

[0040] Generally, however, it is contemplated that the intimate powder contact of the mold body on the mold part may involve engagement of a front surface of the mold body with a recess in the mold part, and thus providing a clearance (e.g., circumferential clearance) that ensures intimate powder contact.

[0041] According to an exemplary embodiment of the method or device of the present invention, the mold body is placed in the cavity such that the resulting through hole is directed towards the chip space. In this way, a preferred supply direction of the lubricant coolant fluid is achieved. The lubricant coolant fluid can reach the cutting edge. The lubricant coolant fluid can wet the chip space, where it dissipates heat and also contributes to chip removal.

[0042] According to an exemplary embodiment of the method or device, the mold body is arranged in the cavity such that the resulting through hole is directed towards the chip-breaking groove and, when viewed from the outlet opening along a plane perpendicular to the direction of the cutting motion, the cross section of the through hole protrudes at least 20% above the chip-breaking groove and contacts the cutting edge. The viewing plane is illustratively perpendicular to this plane and parallel to the direction of the cutting motion.

[0043] In machining tools that perform machining by cutting, there is periodically a defined relative movement between the workpiece and the tool. A characteristic component of this movement is the cutting action, which is related to the cutting speed and is a relevant machining parameter. The direction of the cutting action is also, at least in the exemplary embodiment, the direction in which the main cutting forces are concentrated on the cutting tool.

[0044] An overlap of at least 20% ensures that at least a portion of the lubricating / cooling liquid can reach the chip space and the cutting edge (which is probably located behind the chip space from the perspective of the through hole).

[0045] In an exemplary embodiment, when viewed according to the above rules, the cross-section of the through-hole projects at least 50% above the chip-crushing grooves. In an exemplary embodiment, when viewed according to the above rules, the cross-section of the through-hole projects at least 80% above the chip-crushing grooves. When viewed according to the above rules, the cross-section of the through-hole projects completely (100%) over the chip-crushing grooves. It is understood that the through-hole should not be located too far "up" and away from the chip-crushing groove. Thus, in an exemplary embodiment, the intersection of the longitudinal axis of the through-hole and the outlet opening (opening) of the through-hole towards the chip space is located above the chip-crushing groove, but is less than three or two times the effective diameter of the cross-section of the through-hole in the opening above the chip-crushing groove. In other words, in an exemplary embodiment, the through-hole with its effective cross-section is located just above the chip-crushing groove.

[0046] It should be noted that the term "above the chip-crushing groove" refers to the fact that the chip-crushing groove itself defines the base / bottom of the reference. It is understood that in operation, the location of "above the chip-crushing groove" taking into account the global reference (gravity, floor of the hall) can be below or laterally above the chip-crushing groove.

[0047] In an exemplary embodiment, the through holes at least partially face the chip-breaking grooves, where the lubricating coolant fluid can contribute to heat dissipation, and further act as a lubricant to reduce friction, thus facilitating chip removal and breaking.

[0048] The chip space is the free space adjacent to the cutting edge, in particular behind the cutting edge. The chip space serves to deflect and break the chips. In other words, the chip space is the free space above the chip-breaking groove. During machining, the chips are formed in the chip space and removed via the chip space. The chip guide surface is therefore also exposed to high thermal stresses. It is therefore advantageous to orient the through-hole at least partially into the chip space.

[0049] According to an exemplary embodiment of the method or device, the mold body is positioned in the cavity such that the longitudinal axis of the resulting through hole is oriented at an angle of 45° to 90°, in particular at an angle of 60° to 90°, to the direction of the cutting motion. The through hole is, for example, perpendicular or at an angle of at least 45° (obtuse) to the direction of the cutting motion. Thus, the through hole is not parallel or at an acute angle to the direction of the cutting motion. This ensures a good supply direction of the lubricant coolant fluid.

[0050] An angle between 45° and 90° includes the range of 90° + / - 45°. An angle between 60° and 90° includes the range of 90° + / - 30°. By way of example, the angle between the longitudinal axis of the through hole and the direction of the cutting motion is between 75° and 90°, which includes the angle of 90° + / - 15°.

[0051] According to an exemplary embodiment of the method or device, the mold body is arranged in the cavity such that the longitudinal axis of the resulting through hole is oriented at an angle of 0° to 45°, in particular parallel, to a plane defined as the average plane of the chip-breaking groove shape, including an angle of 0° + / - 45°. The average plane of the chip-breaking groove shape is exemplary oriented perpendicular or substantially perpendicular to the direction of the cutting movement. The longitudinal axis of the through hole is parallel or at an acute angle to the average plane of the chip-breaking groove shape.

[0052] According to an exemplary embodiment of the method or device, the mould body is arranged in the cavity in such a way that the resulting through hole is oriented at an angle between 0° and 45° (0°+ / -45°), in particular parallel to the main extension direction of the shaft of the pressed article. According to a further exemplary embodiment, the resulting through hole is oriented at an angle between 0° and 30° (0°+ / -30°) relative to the main extension direction of the shaft. According to a further exemplary embodiment, the resulting through hole is oriented at an angle between 0° and 15° (0°+ / -15°) relative to the main extension direction of the shaft.

[0053] According to an exemplary embodiment of the method or device, the feed direction of the mold body is perpendicular to the main pressing direction of the cavity. If the main pressing direction is vertical, according to this embodiment, the feed direction of the mold body is horizontal. The mold body can be called a horizontal slider.

[0054] According to an exemplary embodiment of the method or apparatus, the die body is disposed within the cavity at or at least adjacent to the neutral phase of the pressed article. According to an exemplary embodiment of the method or apparatus, the die body is disposed within the cavity at least substantially at or at least adjacent to the neutral phase of the pressed article.

[0055] This is at least approximately true. The neutral phase is that part of the hard metal powder in the cavity that does not move or moves only minimally during compression of the hard metal powder. When compressing hard metal powder, the powder in the edge region of the pressed article is displaced over a considerable distance, for example by a punch acting directly on it. However, in the center of the cavity (neutral phase) there is an area where the hard metal powder moves only slightly during the pressing process compared to the powder in the edge region. It is conceivable to design the pressing tool (apparatus) and the pressed article in such a way that the die body is located in an area where there is only little powder movement during compression. This reduces any forces acting on the die body during compression by (at least approximately) being located in the neutral phase, especially when the die body is positioned at a right angle or otherwise at an obtuse angle to the main pressing direction.

[0056] It is understood that the term neutral phase does not necessarily mean that there must be absolutely no motion at the microscopic level. Instead, it refers to a region within the cavity that undergoes minimal motion / displacement under given conditions.

[0057] The advantage of this configuration, at least in the exemplary embodiment, is that the rod-shaped operating portion of the die body experiences less shear force during compression of the hard metal powder, which prevents damage or even breakage of the die body during compression.

[0058] According to an exemplary embodiment of the method or device, the chip space of the pressed article is at least partially defined by the operating surface of the movable die part. In other words, the die part defines the chip space and, therefore, also the chip breaking grooves. However, another surface of the die part can serve as an abutment area for the die body. In this way, a preferred orientation of the through holes towards the chip space and the chip breaking grooves can be achieved.

[0059] According to an exemplary embodiment of the method or apparatus, the tip space of the pressed article is at least partially defined by another movable die part, according to this embodiment, the (first mentioned) die part partially forms the geometric shape of the pressed article and also serves as an abutment area for the die body. The further (last mentioned) die part at least partially forms the chip breaking grooves and the chip space, and possibly also the geometric shape of the cutting edge. When viewed obliquely from the front side of the exemplary rod-shaped die body, the first die part is located between the die body and the last die part. In this way, a preferred orientation of the cutting edge, the chip breaking grooves and the through holes towards the chip space can be achieved.

[0060] If at least one (first) die part defines an abutment area for the die body and at least one (second) die part defines a chip-breaking groove and a chip space, the die parts can generally also include different feed directions. As an example, the first die part has a vertical feed direction. As an example, the second die part has a horizontal feed direction. It is also conceivable that both die parts have parallel feed directions.

[0061] If at least one (first) die part defines an abutment area for the die body and at least one (second) die part defines a chip breaking groove and a chip space, it is conceivable to design one die part as a punch and the other die part as a slider. However, it is also conceivable to design both die parts as punches. This includes a configuration in which one of the two die parts is a vertical punch and the other of the two die parts is a horizontal punch / cross punch.

[0062] In an embodiment using a first die part and a second die part, regardless of whether the feed directions of the first die part and the second die part are parallel or perpendicular, the feed direction of the die body is perpendicular to the feed direction of the first die part and perpendicular to the feed direction of the second die part.

[0063] According to an exemplary embodiment of the method or device, at least the chip spaces and the through holes are formed with little or no post-processing with respect to their geometric shape in the die. This preferably applies to the entire pressed article. In this way, through holes with a preferred orientation can be produced without significant further effort within the press cycle. However, it is understood that there are further obligatory processing steps, such as, for example, sintering, to produce a cutting tool based on the pressed article (compact).

[0064] According to an exemplary embodiment of the method or device, the mould body is arranged in the cavity such that the outlet openings of the through holes facing the chip space are arranged on a surface of the pressed article oriented at an angle of 0° to 45° (0°+ / -45°), in particular at an angle of 0° to 30° (0°+ / -30°) to the main pressing direction. The outlet openings can also be called apertures. In the region of the outlet openings, the front face of the mould body comes into contact with the mould part. In an exemplary embodiment, the surface of the outlet openings is parallel or approximately parallel to the main pressing direction.

[0065] According to an exemplary embodiment of the method or apparatus, the die parts and the die body are brought into a powder-tight relative position before filling the cavity with hard metal powder. The powder-tight relative position does not necessarily correspond to the final relative position after the pressing step. This includes, for example, positioning the die body with its front face in powder-tight contact on a flat surface of the die part, but the die part can then be moved along the flat surface along its front face. However, in an exemplary embodiment, at least the die body is placed in an intermediate or even final end position with the powder in the cavity tightly packed relative to the die before filling the cavity.

[0066] According to an exemplary embodiment of the method or apparatus, the die parts and the die body are brought into intimate powder contact with each other after filling the cavity with hard metal powder. This includes, for example, an arrangement in which the hard metal powder in the cavity is first displaced by the die body until the powder in the cavity reaches a tightly packed intermediate position or even a final end position. A die part can then be fed and moved into the cavity. The die part is, for example, arranged to displace the powder forward of the front face of the die body. This occurs due to the tightly packed powder position, nevertheless allowing relative movement between the die part and the die body.

[0067] According to an exemplary embodiment of the method or apparatus, at least the die parts or the die body are actively moved after filling the cavity with the hard metal powder. By way of example, the die parts act as punches which further contribute to the compaction of the hard metal powder. The movement of the die parts and / or the die body can occur in a powder-intimate relative position.

[0068] According to an exemplary embodiment of the method or apparatus, the step of feeding the mold parts and the mold body includes engaging a front surface of the mold body within a stationary recess in the mold part, the stationary recess preferably being sealed to provide a powder tight fit.

[0069] In addition to flush contact, an at least partial engagement of the die body with its operating part in a recess on the die part is also conceivable. Due to the different feed directions, the die part and the die body interlock with each other in this way. This results in an at least partially form-fitted position. In this way, for example, the die body can be partially supported by the die part during the pressing process.

[0070] According to an exemplary embodiment of the method or apparatus, the die parts have a closure for the stationary recess, which seals the stationary recess in a powder-tight manner when the die body is not engaged. In this way, the ingress of powder into the stationary recess can be avoided or minimized when the die body is not yet engaged. Thus, the die parts and the die body can be moved closer to their final end positions without hard metal powder accumulating in the stationary recess.

[0071] According to an exemplary embodiment of the method or apparatus, the closure is arranged as a flexible closure. In an exemplary embodiment, the closure is displaced during engagement of the mold body. In an exemplary embodiment, the closure is compressed during engagement of the mold body. As an example, the closure is arranged as a spring-loaded piston or a spring-loaded flap, which is moved by the mold body during engagement. It is also generally contemplated that the closure portion may be configured as a resilient closure portion, which is compressed or otherwise deformed by the mold body during engagement.

[0072] According to an exemplary embodiment of the method or apparatus, the step of feeding the mold parts and the mold body includes closely disposing the powder on a front surface of the mold body against an abutment area on the mold parts, i.e., flush or near flush abutment of the front surface of the mold body on / in the abutment area of ​​the mold parts may result. The target distance between the die body front face and the die part abutment area is greater than 0 but less than the average or minimum particle size of the hard metal powder. Thus, ideally, at least in the exemplary embodiment, in a given powder contact configuration, the hard metal powder cannot penetrate into the intermediate space (remaining gap) between the die body front face and the abutment area.

[0073] The flush contact of the front surface of the mold body on the contact surface of the abutment area of ​​the mold part can also be an intermediate step, provided that the mold part is at least partially engaged in a stationary recess on the mold part. The intermediate step already allows a relative movement of the closely-contacted powder. In this way, for example, by moving the mold part relative to the mold body, the mold body can turn its front surface away from the stationary recess.

[0074] According to an exemplary embodiment of the method or apparatus, the mold body takes at least one abutment position along its feed direction, and the mold parts are moved against the front face of the mold body during their movement in the feed direction, thereby displacing any powder particles therein. In other words, during the relative movement between the mold parts and the mold body, the mold parts can thus clear the front face of the mold body like a stripper.

[0075] According to an exemplary embodiment of the method or device, the feed direction of the die part is parallel to the main pressing direction. The die part can therefore be provided as a punch, at least as a pre-press punch.

[0076] According to an exemplary embodiment of the method or device, the feed direction of the die parts is perpendicular to the main pressing direction. According to an exemplary embodiment of the method or device, the feed direction of the die parts is perpendicular to the feed direction of the die body. By way of example, the die parts can be arranged as side sliders with rod-shaped operating parts.

[0077] According to an exemplary embodiment of the method or apparatus, the die part is a punch. According to a further exemplary embodiment, the die part at least partially contributes to the compaction of the hard metal powder.

[0078] According to an exemplary embodiment of the method or device, the die part is a slider. A slider is a die part that does not move or moves only slightly during the pressing process, in particular for compressing hard metal powder. For example, the movement of a die part arranged as a slider in a die during the pressing process is insignificant, the amount of which is less than one tenth of the stroke of the main punch.

[0079] According to an exemplary embodiment of the method or device, at least one further die part is used in addition to the die part arranged as a punch, which further die part is preferably designed as a punch with a feed direction parallel or perpendicular to the feed direction of the die part. This takes into account the fact that the chip space with the cutting edge and the chip breaking grooves can also be defined by die parts that are not used for the close contact of the powder with the die body. These further die parts are the main punch (longitudinal punch), the side punch (transverse punch), but basically a slider.

[0080] According to an exemplary embodiment of the method or apparatus, the die part is arranged as a pre-press punch and the further die part is arranged as a punch with parallel feed directions, the pre-press punch and the die body in the cavity are positioned to move towards each other through the introduced hard metal powder and bring the powder into intimate contact with each other, comprising at least partially compressing the hard metal powder by the pre-press punch, which later moves parallel to the pre-press punch but with a larger compression stroke, preferably the punch forms a significant part of the area in the pressed article that defines the through hole along its longitudinal extension.

[0081] In this way, on the one hand, intimate contact of the powder of the die body against the die parts is possible, and on the other hand, it is ensured that a significant portion of the pressed article is subjected to the desired degree of pressure during the main pressing step.

[0082] In an exemplary embodiment, the die body is placed in a neutral phase so that the hard metal powder moves only slightly during compression.

[0083] It will be understood that the features of the present disclosure, both above and below, may be used not only in the combinations specified herein but also in other combinations or as isolated features without departing from the spirit and scope of the present disclosure. [Brief description of the drawings]

[0084] Further features and advantages are disclosed in the following description of several exemplary embodiments with reference to the drawings. [Figure 1] FIG. 2 is a top view of a cutting tool supported by a holder. [Diagram 2] FIG. 2 is a cutaway side view of the cutting tool according to FIG. [Diagram 3] FIG. 3 is a perspective front view of the cutting tool according to FIGS. 1 and 2; [Figure 4] 4 is another view according to FIG. 3 with a partial cross-sectional view of the cutting tool, illustrating the through hole. [Diagram 5] FIG. 5 is a front view of the cutting tool shown in FIGS. 3 and 4, the observation plane being perpendicular to the axis of the through hole. [Figure 6] 6 is another front view of the cutting tool according to FIG. 5, showing various possible positions of the through hole. [Figure 7] 7 is a longitudinal section through the cutting tool according to FIGS. 3 to 6, the section being on the axis of the through hole. [Figure 8] 1 is a simplified diagram of an apparatus for producing a hard metal pressed article including a die. [Figure 9] FIG. 9 is a further view of the apparatus according to FIG. 8, in which a filling shoe for filling the cavities with hard metal powder is arranged above the die. [Figure 10] FIG. 10 is a further view of the apparatus according to FIGS. 8 and 9, in which the die part arranged as a punch is moved into a starting position for compressing the hard metal powder. [Figure 11] 11 shows a view of the device according to FIG. 10, in which at least one die part arranged as a punch and a die body having a rod-shaped operating part are moved at least partially into the cavity. [Figure 12] FIG. 12 is a diagram of the apparatus according to FIG. 11, in which the mould parts and the mould body assume a relative position such that the powder in the cavity is in intimate contact. [Figure 13] FIG. 13 is a detailed view based on FIG. 12 illustrating the relative positions between the mold parts and the mold body, showing an exemplary embodiment of positioning such that the powder is in intimate contact. [Figure 14] FIG. 13 is a further detailed view based on FIG. 12 illustrating the relative positions between the mold parts and the mold body, showing an exemplary embodiment of positioning such that the powder is in intimate contact. [Figure 15] FIG. 13 is a diagram of the apparatus according to FIG. 12, where the associated punch in the die cavity reaches a final position for compressing the hard metal powder, thereby forming a pressed article. [Figure 16] FIG. 16 is a diagram of the apparatus according to FIG. 15, in which the die body is moved out of the through hole formed in the pressed article. [Figure 17] 17. View of the apparatus according to FIG. 16, where the upper punch part is moved out of the cavity. [Figure 18] FIG. 18 is a view of the device according to FIG. 17, in which the lower punch ejects the pressed article from the cavity. [Figure 19] FIG. 13 is a simplified side view of another exemplary embodiment of a press article having two through holes. [Figure 20] FIG. 19 is a simplified perspective view of another pressed article having a through hole, illustrating the concept of a cutting tool modified from the apparatus according to FIGS. [Figure 21] FIG. 19 is a simplified diagram of another embodiment of an apparatus for producing hard metal pressed articles, modified with respect to the apparatus according to FIGS. [Figure 22] FIG. 1 is a simplified block diagram for illustrating an exemplary embodiment of a method for producing a hard metal pressed article, in particular a method for producing a sintered feed part for a cutting tool. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0085] 1-7, an exemplary embodiment of a cutting tool 10 is shown, the manufacture of which is the subject of various aspects of the present disclosure. As already mentioned, the cutting tool 10 shown in FIG. 1 can be manufactured based on a pressed article (compact) produced under high pressure by compressing hard metal powder.

[0086] In Figures 1 and 2, cutting tool 10 is shown to be housed in a holder 12 during use. Cutting tool 10, at least in the exemplary embodiment, is made from a hard metal material. Cutting tool 10 includes a shaft 14 that seats in a mounting seat 16 of holder 12 for clamping cutting tool 10. Cutting tool 10 includes a cutting edge 20 bordered by a chip breaking groove 22, also see the perspective views of Figures 3 and 4. This chip breaking groove 22 may also be referred to as a chip trough.

[0087] From Figures 2 to 4 it can be seen that the cutting tool 10 has through holes 26 which in an exemplary embodiment form lubricant-coolant channels 28 for the coolant-lubricant. Figure 2 shows that a lubricant supply 30 for supplying a lubricant-coolant fluid is associated with the lubricant-coolant channels 28 in a portion of the holder 12. In this way, the lubricant-coolant fluid can be introduced into the lubricant-coolant channels 28 and flow out through an outlet opening 32 (Figures 3 and 4) towards the chip-breaking grooves 22 and the cutting edge 20. The perspective views of Figures 3 and 4 show the path of the lubricant-coolant channels 28 in the cutting tool 10.

[0088] The orientation of the lubricant / coolant channels 28 and the through holes 26 which respectively form said channels are further illustrated with reference to Figures 5 and 7. Figures 5 and 6 show a front view of the cutting tool 10, in which the observation plane is perpendicular to the axis 34 of the lubricant / coolant channels 28. In this orientation, it can be seen that the outlet openings 32 (and / or cross sections) of the through holes 26 are arranged above the (front) cutting edge 20 - in this case as the highest point of the chip-breaking grooves 22 - when viewed in the extension of the lubricant / coolant channels 28 and their axes 34, respectively. As indicated previously, the term "above" refers to the highest point of the chip-breaking grooves 22 in the extension of the lubrication / coolant channel 28, which essentially forms the basis of the selected arrangement. When looking from behind along the axis 34 through the lubrication / coolant channel 28 towards the cutting edge 20, the cross section of the lubrication / coolant channel 28 must be at least partially above the part of the cutting edge 20 visible from this view (this part is in front of the lubrication / coolant channel 28).

[0089] 6 shows, in addition to FIG. 5, other possible positions of the outlet opening 32 and the lubricant coolant channel 28, respectively. The dashed circle shows an alternative positioning of the lubricant coolant channel 36 with its axis 38. The lubricant coolant channel 36 is arranged with its cross section at least partially above the chip-breaking groove 22. In various embodiments, the through hole 26 at the outlet opening 32 is arranged with its cross section at least partially above the chip-breaking groove 22 and at least partially above the cutting edge 20.

[0090] 5-7, the reference numeral 40 denotes a surface on which the exit opening 32 is located. In an exemplary embodiment, the surface 40 is oriented perpendicular to the axis 34 of the through hole 26. In the current configuration of the cutting tool 10, the surface 40 and the exit opening 32 can be manufactured directly in the die by two contacting die parts (die part and die body) having different feed directions, including, for example, orthogonal feed directions.

[0091] In addition, Figures 6 and 7 show a chip space, indicated by reference number 42, located above the chip-breaking grooves 22. The selected representation by dashed lines is merely exemplary. The cutting edge 20, the chip-breaking grooves 22 and the chip space 42 are subjected to high stresses during machining with the cutting tool 10. It is therefore advantageous if the lubricating cooling fluid (see arrow 48 in Figure 7) can be supplied to the cutting edge 20, the chip-breaking grooves 22 and the chip space 42 in a preferred orientation.

[0092] 7 further indicates by arrow 44 the direction of the cutting action during machining with cutting tool 10. Cutting action 44 is the movement of cutting tool 10 relative to the workpiece being machined (not shown in FIG. 7). Reference numeral 46 indicates by a dashed line a plane perpendicular to the direction of cutting action 44 and touching the highest point of chip-breaking groove 22, in this case in extension of axis 34 and lubrication / coolant channel 28. Plane 46 also serves to indicate the overall orientation of chip-breaking groove 22 in the exemplary embodiment.

[0093] According to an exemplary embodiment, the through hole 26 with its outlet opening 32 and / or its cross section is at least partially located above the plane 46. At least partially located above the plane 46 exemplarily relates to at least 20% of the cross section of the outlet opening 32. It is understood that further values ​​are conceivable, such as 50%, 80% or 100%. At 100%, the through hole 26 with its outlet opening 32 is completely above the plane 46. The above-mentioned orientation allows a large portion of the lubricating / cooling fluid 48 to be supplied in particular to the cutting edge 20, the chip-crushing groove 22 and / or the chip space 42.

[0094] With reference to Figures 8 to 18, a method for manufacturing a blank (pressed article, compact) suitable for manufacturing the cutting tool 10 according to Figures 1 to 7 or an equivalent cutting tool is shown.

[0095] Fig. 8 shows an apparatus 50 for producing hard metal pressed articles for producing green parts for cutting tools. The apparatus 50 comprises a die 52 including a moving part and a fixed part for forming a cavity 54. In the cavity 54, hard metal powder can be compressed to form a pressed article 60, the shape of which is the basis for the production of the cutting tool 10. Fig. 10 further shows a control unit, indicated by the reference numeral 56, which appropriately controls the apparatus 50 and its components for producing the pressed article 60.

[0096] In Figure 8, a press article 60 is shown in dashed lines. The press article 60 includes a through hole 62 oriented toward a cutting edge 64 and / or chip-breaking groove 66, and an imaginary chip space above the chip-breaking groove 66. See the above comments relating to Figures 5-7. The press article 60 further includes a shaft 68.

[0097] The die 52 of the apparatus 50 includes at least one stationary die part 70, which in the exemplary embodiment at least partially defines the circumference of the pressed article 60. The stationary die part 70 is provided with a guide 72 for a die body 74. The die body 74 is illustratively configured as a slider. The die body 74 has an approximately rod- or pin-shaped operating part 76. Towards the cavity 54, a front face 78 is provided forming the end of the operating part 76. The operating part 76 forms the through hole 62 in the pressed article 60. The die 52 illustratively includes further die parts, such as a movable die part 80 illustratively configured as a lower punch 82.

[0098] In the configuration shown in Figure 8, the cavity 54 of the die 52 is filled with hard metal powder 86. This is shown in Figure 9. For filling purposes, a so-called filling shoe 84 is provided on the side of the cavity 54 opposite the lower punch 82. The hard metal powder 86 is allowed to flow down into the cavity 54 supported by gravity (see arrow 88 indicating gravity). 9 also illustrates the die body 74 being moved into a ready position relative to the cavity 54. After filling the fill shoe 84, a sufficient amount of hard metal powder 86 is present in the cavity 54 of the die 52 to form a pressed article.

[0099] The orientation shown with reference to arrow 88 (gravity) may also be used within the scope of this disclosure to define terms such as above, top, below, bottom, side, lateral, etc. Arrow 88 is parallel to the vertical. Horizontal planes extend perpendicular and / or perpendicular to arrow 88. Those skilled in the art know that filling with the filling shoe 84 is typically performed "from above."

[0100] 10 shows the state of the apparatus 50 when the fill shoe 84 (FIG. 9) is moved away from the top of the die 52, thereby providing space for an additional die part, as compared to the movable die part 92, exemplarily configured as an upper punch 94. By way of example, the die part 92 has a stationary recess 98 shown in dotted lines, although this is not required.

[0101] The die part 92 has an operating surface 100 that at least partially defines the shape of the pressed article 60. In the exemplary embodiment according to Fig. 10, the operating surface 100 defines at least the chip breaking grooves 66 and the cutting edge 64 in cross section, see Figs. 8 and 17. In the exemplary embodiment, a further movable die part 102 is disposed adjacent to the die part 92, exemplarily as another upper punch 104. The die part 102 defines the area of ​​the pressed article 60 within which the operating portion 76 of the die body 74 extends to form the through hole 62.

[0102] In the exemplary embodiment, die body 74 has a horizontal feed direction 110. In the exemplary embodiment, die part 80 (lower punch 82) has an upward vertical feed direction 112. Die part 92 (upper punch 94) has a downward vertical feed direction 114. Die part 102 (upper punch 104) has a downward vertical feed direction 116.

[0103] As indicated above, the control unit 56 serves to accurately and precisely control the movements of the various movable components of the apparatus 50. In particular, the movements of the die body 74, and of the die parts 80, 92, 102 (see feed directions 110, 112, 114, 116) can be accurately and precisely controlled, perhaps even in the micrometer range.

[0104] 10 further illustrates by arrow 118 a primary pressing direction 118 of the mold parts 80, 92, and 102 in the die 52 of the apparatus 50. In an exemplary embodiment, both the lower punch 82 and the upper punches 94, 104 are moved at least partially toward one another, resulting in a vertically oriented primary pressing direction 118.

[0105] FIG. 11 shows the die body 74 moving in the feed direction 110 into the cavity 54 and the hard metal powder 86 moving. The die body 74 approaches an abutment area 124 defined by the upper punch 94 in the exemplary embodiment. The abutment area 124 corresponds to the surface 40 where the exit opening 32 of the through hole 26 is located in the cutting tool 10 illustrated with reference to FIGS. 1-7. FIG. 11 also shows that in the exemplary embodiment, the punches 82, 94, 104 are not necessarily moved synchronously at the same time. Rather, the arrow 114 indicates, for example, that the punch 94 moves in front of the punch 104. The goal of the movement of the punch 94 (die part 92) and the die body 74 is a preferred relative position, particularly a relative position where the powder is in intimate contact.

[0106] 11 further indicates by reference 122 a so-called neutral phase. The neutral phase 122 is a volume region during the pressing process in which only relatively small movements occur during the compression of the hard metal powder 86. The control unit 56 of the device 50 controls in particular the die parts 80, 92, 102 (i.e. for example the punches 82, 94, 104) so ​​that the neutral phase 122 is located in the vicinity of the operating part 76 of the die body 74. Thus, when the die body 74 is positioned in the neutral phase 122, stresses on the die body 74 during the pressing process are reduced.

[0107] Figure 12 shows, based on figure 11, the state in which the upper punch 94 (mold part 92) is in powder-tight contact with the mold body 74. The upper punch 94 has almost or completely reached its final end position in the cavity 54. The operating surface 100 forms part of the pressed article 60, e.g. the cutting edge 64 and / or the chip breaking grooves 66. The powder-tight contact between the mold body 74 and the punch 94 allows the formation of through holes 62 in the pressed article, where the through holes 62 are formed during the pressing process in the die 92 and are not formed by a subsequent material removal process.

[0108] 12 shows that following the pressing action of the upper punch 94, the upper punch 104 (arrow 116) and the lower punch 82 (arrow 112) are further advanced in the main pressing direction 118 to further compact the hard metal powder 86. The punches 94, 104, and 82 may move simultaneously, at least temporarily.

[0109] 13 and 14 each show, by way of a detailed view of the view shown in FIG. 12, possible configurations for the desired powder intimate contact between the die part 92 (upper punch 94) and the die body 74.

[0110] In Fig. 13 the mould body 74 is shown, with its operating part 76 and front face 78, which can engage in the stationary recess 98. If the corresponding circumferential gap is small enough, a relative position is obtained between the mould body 74 and the mould part 92, which provides a tight powder contact. In the exemplary embodiment according to Fig. 13 a closure part 106 is arranged in the stationary recess 98, which closure part is designed, for example, as a closure piston or a closure flap. The closure part 106 can be pressed into the stationary recess 98 by the mould body 74 against the force of the preload element 108.

[0111] The engagement movement is indicated by an arrow indicated by the reference number 110. In other words, in this exemplary embodiment, the front face 78 of the mold body 74 moves beyond the abutment area 124 on the mold part 92. However, it is also conceivable that the mold body 74 remains temporarily at the abutment area 124 with its front face 78 during the feed movement. This allows the mold part 92 to be fed in its feed direction 114 after the mold body 74 has been fed; in this context, see FIG. 11. If the front face 78 is oriented exactly opposite the stationary recess 98 in the final position of the mold part 92, the mold body 74 can move with its front face 78 into the stationary recess.

[0112] In an exemplary embodiment, the closure portion 106 seals the stationary recess 98 in a powder tight manner even during the feed motion (arrow 114 in FIGS. 11 and 12) of the die part 92. In other words, the closure portion 106 can flush seal the stationary recess 98 such that the hard metal powder 86 cannot accumulate therein. This prevents the die body 74 from potentially forcing the hard metal powder 86 into the stationary recess 98 during engagement.

[0113] Fig. 14 shows an alternative configuration. According to this embodiment, no stationary recess for the die body 74 is provided in the die part 92 (upper punch 94). Instead, the positioning of the compacted powder is achieved by flush contact of the front face 78 in the abutment area 124, which in Fig. 14 corresponds to the surface of the die part 92 facing the front face 78. The die part 92 is exemplarily flat or planar in the area opposite the front face 78, so that a relative movement between the die body 74 and the die part 92 in the feed direction 114 of the die part 92 is conceivable while keeping the powder in intimate contact.

[0114] In this way, the mold body 74 can be moved with its front face 78 along its feed direction 110 to its final position in the cavity 54 (see FIG. 11 ). The mold part 92 can then be fed in its feed direction 114, displacing the hard metal powder 86 in front of the front face 78 of the mold body 74. This also results in an intimate contact of the powder and thus the possibility of integrally forming the through hole 62 during the pressing process in the die 52.

[0115] The pressing process using the device 50 illustrated with reference to FIGS. 8 to 12 and 15 to 18 can essentially be combined with any of the variants illustrated in FIGS.

[0116] Based on the representation of Figure 12, Figure 15 shows all die parts 80, 92, 102 (punches 82, 94, 104) reaching their final end positions relative to the cavity 54 and the hard metal powder 86 contained therein. Similarly, the die body 74 is in an end position relative to the cavity 54. Thus, the hard metal powder 86 is compressed to the extent that the desired pressed article 60 is formed.

[0117] Figures 16 and 17 show the start of the demolding process to retrieve the manufactured pressed article 60. In Figure 16, the mold body 74 is first moved out of the cavity 54 (see arrow 110). The through hole 62 remains in the pressed article 60. Figure 17 shows that the upper punch 94, 104 is lifted out of the pressed article 60 and guided upwards out of the die 52 (see arrows 114, 116). This exposes the cutting edges 64 and chip breaking grooves 66 of the pressed article 60. The pressed article 60 is then illustratively lifted by the lower punch 82 and directed upwardly from the die 52. See arrow 112 in FIG. 18, in which the resulting pressed article 60 is also shown in dashed representation outside of the cavity 54. The pressed article 60 features an integrated through hole 62.

[0118] FIG. 19 shows another exemplary embodiment of a press article 160 suitable for manufacturing a reversible cutting insert with two cutting edges. The press article 160 has a through hole 162 that can function as a lubricant coolant channel. The through hole 162 is aligned with the cutting edge 164 and / or the chip breaking groove 166 adjacent to the cutting edge 164. The arrow designated by reference number 168 illustrates the direction of the cutting action during machining with the cutting edge 164. The cross section of the through hole 162 in its opening area relative to the chip breaking groove 166 is at least partially perpendicular to the direction of the cutting action 168 and above the plane in contact with the cutting edge 164. The shaft of the press article is designated by reference number 170.

[0119] In this embodiment, the press article 160 is arranged with point symmetry. As a result, the press article 160 also has through holes 172 that can serve as lubricant coolant channels. The through holes 172 are aligned with the cutting edges 174 and / or chip breaking grooves 176 adjacent the cutting edges 174. The arrow designated by the reference number 178 illustrates the direction of the cutting action during machining with the cutting edge 174. The cross section of the through hole 172 in the area of ​​its opening to the chip-breaking groove 176 lies, at least in part, perpendicular to the direction of the cutting action 178 and above a plane intersecting the cutting edge 174.

[0120] Pressed article 160 may be manufactured, for example, using a powder press having a tooling concept similar to that of apparatus 50 according to Figures 8-18. Other concepts are contemplated according to alternative embodiments of the present disclosure.

[0121] FIG. 20 shows another alternative approach for the tool concept by a perspective view of a press article 260. The press article 260 is designed at least similarly to the press article 60 illustrated above with reference to FIGS. 8 to 18. The press article 260 has a through hole 262 advantageously oriented to a cutting edge 264 of the press article 260 and a chip-breaking groove 266 adjacent to the cutting edge 264. The through hole 262 extends along an axis 268. The shaft of the press article 260 is indicated by the reference number 270. To form the through hole 262, a die body 274 is provided having an operating part 276, a front face 278 of the die body facing the cutting edge 264 and the chip-breaking groove 266, respectively, during the pressing process. The die body 274 is exemplarily configured as a slider with a horizontal feed direction 310.

[0122] In Figure 20, press article 260 is shown in a lying orientation. Further reference is made to a Cartesian coordinate system designated by numerals 284, 286, 288. Arrow 284 indicates horizontal extension (e.g., longitudinal extension). Arrow 286 indicates vertical. Arrow 288 indicates horizontal extension (e.g., depth extension). Arrows 284, 288 together define a horizontal plane. Arrow 286 is perpendicular to this horizontal plane.

[0123] 8-18, it can be seen that pressed article 260 is tilted at 90 degrees. In FIG. 20, arrow 282 indicates a lower punch for producing pressed article 260. Similarly, arrow 304 indicates an upper punch. Punches 282 and 304 are positioned opposite each other in a die (not shown in FIG. 20) and are movable toward each other in a vertical direction 286 to compress the hard metal powder to form pressed article 260.

[0124] In the "lying" configuration according to Fig. 20, the cutting edges 264, and in particular the chip-breaking grooves 266, are formed by a laterally feedable die part 292. An operating surface 300 of the die part 292 is shown in Fig. 20 by dashed lines. The operating surface 300 corresponds to the desired configuration of the chip-breaking grooves 266 and the cutting edges 264, respectively, and forms them at least in the cross section of the die. A feed direction (see arrow 314 in FIG. 20) is illustratively parallel to direction 288. Die part 292 is illustratively configured as a lateral slider (cross slider) or a lateral punch (cross punch 294).

[0125] Feed direction 314, in the exemplary embodiment, is perpendicular to feed direction 310 of die body 274. Die part 292 has a contact area 324 where front face 278 of die body 274 makes intimate powder contact. Also in this manner, horizontally feedable die part 292 and horizontally feedable die body 274 can be used to produce through holes 262 having a preferred orientation in pressed article 260.

[0126] Figure 21 illustrates another exemplary embodiment of an apparatus for producing hard metal stamping articles, generally designated by the numeral 350. The apparatus 350 is configured generally similarly to the apparatus 50 illustrated with reference to Figures 8-18.

[0127] The apparatus 350 includes a die 352 for forming a cavity 354 in which a pressed article 360 ​​can be produced from hard metal powder. The pressed article 360 ​​has through holes 362 which can function, for example, as lubricant coolant channels. The through hole 362 is advantageously oriented relative to a cutting edge 364 and a chip breaking groove 366 adjacent the cutting edge 364. The press article 360 ​​has a shaft 368. In general, the press article 360 ​​is also suitable for manufacturing cutting tools 10, see, for example, the designs illustrated with reference to Figures 1-7.

[0128] Generally as described above, die 352 includes at least one fixed die part 370 that defines a perimeter of, for example, pressed article 360. Also provided on fixed die part 370 is a guide for a die body 374 having a manipulator 376 that defines aperture 362. Manipulator 376 has a front surface 378.

[0129] As mentioned above, the die 352 includes a die part exemplarily configured as a lower punch 382 having a feed direction 412. Additionally, a die part is provided that is exemplarily configured as an upper punch 394 having a feed direction 414. The punch 394 has an operating surface 400 that, in the exemplary embodiment, is used to form the cutting edge 364 and the chip crushing grooves 366.

[0130] The difference between the device 50 according to Figures 8 to 18 and the device 350 according to Figure 21 is that the die body 374 having the front surface 78 does not come into contact with the punch 394, which forms the chip crushing grooves 366 and the cutting edge 364 by its operating surface 400. Instead, the die 352 includes another die part, illustratively configured as a (separate) upper punch 404 having a feed direction 416. The punch 404 defines a portion of the shaft 368 of the press article 360 ​​through which the through hole 362 extends. In addition, the punch 404 has an abutment area 424 against the die body 374. In the illustrative embodiment, an extension 426 of the punch 404 forms the abutment area 424. For example, a stationary recess 398 is formed into which the front surface 378 of the operating portion 376 can pass.

[0131] At the contact region 424, the die body 374 can come into contact with the punch 404 so as to bring the powder into intimate contact with the punch 404. The configuration of the device 350 illustrated with reference to Fig. 21 is suitable for a pressed article 360, for example, in which the cutting edge 364 and the chip crushing grooves 366 are arranged away from the opening of the through hole 362, even though not explicitly shown in Fig. 21.

[0132] 22, an exemplary embodiment of a method for manufacturing hard metal pressings is shown with reference to a block diagram. The method is particularly suitable for manufacturing sintered green parts for cutting tools with integrated lubrication and coolant channels. The method allows for a preferred orientation of the lubrication and coolant channels relative to the cutting edge and / or chip breaking grooves of the cutting tool. The method begins with step S10.

[0133] Step S12 refers to providing a die for forming a cavity for compressing hard metal powder to produce a pressed article. Step S12 includes a sub-step S14, which includes providing a movable die part at least partially defining the shape of the pressed article with an operating surface. Step S12 further includes a sub-step S16, which includes providing a movable die body, exemplarily configured as a slider, which serves to form a through hole in the pressed article. The die part and the die body have different feed directions relative to each other, both directions being in particular obtuse or perpendicular. The die body is exemplarily configured as a punch or a slider.

[0134] In step S18, the die parts and the die body are fed such that the die body contacts and intimates the powder on the die parts. In this way, a through hole can be formed during the pressing process. Step S18 can be combined with a step of filling the cavity with hard metal powder. In general, it is conceivable to first fill the cavity with hard metal powder and then move the die parts and the die body into the cavity. The feed movements of the die body and the die parts can be staggered in time. In at least some examples, overlapping feeds are conceivable. Once the die body has moved to a target position in the filled cavity, the die parts can be used to displace any hard metal powder in front of the front face of the die body.

[0135] In a further step S20, the hard metal powder is compressed to obtain a pressed article. For this purpose, one punch or several punches are usually used. Generally, a die part can be designed as a punch and contributes to the compression. A further step S22 comprises demoulding the pressed article. This comprises, for example, removing the die body in sub-step S24 and the die part from the cavity in sub-step S26.

[0136] The method ends in step S28. The pressed article is available for further manufacturing steps (e.g., sintering).

Claims

1. A method for producing a sintered green part for a hard metal pressed article, in particular a cutting tool (10), comprising the steps of: providing a die (52, 352) forming a cavity (54, 354) for producing a pressed article (60, 160, 260, 360) having at least one cutting edge (64; 164, 174; 264) and at least one chip crushing groove (66; 166, 176; 266) associated with a chip space (42), the process comprising: Providing a movable die part (92, 292, 404), in particular a punch (94) or slider (294), which at least partially defines the shape of a press article (60, 160, 260, 360) having an operating surface (100, 300), the die part (92, 292, 404) being feedable in a first feed direction (114, 314); providing a movable mould body (74, 274, 374) having a rod-like operating part (76, 276, 376) for forming the through-hole (62; 162; 172; 262), the rod-like operating part (76, 276, 376) having in particular a front surface (78, 278), the mould body (74, 274, 374) being feedable in a second feed direction (110, 310), the first feed direction (114, 314) and the second feed direction (110, 310) being inclined to each other at an angle of at least 45°, forming a pressed article (60, 160, 260, 360) from hard metal powder (86) introduced into said cavity (54, 354) and compressed in at least one primary pressing direction (118), comprising: providing a mold part (92, 292, 404) and a mold body (74, 274, 374) such that the mold body (74, 274, 374) is positioned with its operating portion (76, 276, 376) in an abutment area (124, 324) on the mold part (92, 292, 404) to intimately contact the powder within the cavity (54, 354) to form the through hole (62; 162, 172; 262).

2. The method of claim 1, wherein the mold body (74, 274, 374) is positioned within the cavity (54, 354) such that the resulting through hole (62; 162, 172; 262) is oriented toward the tip space (42).

3. 3. The method according to claim 1 or 2, wherein the mold body (74, 274, 374) is positioned in the cavity (54, 354) so ​​that the resulting through hole (62; 162, 172; 262) faces the chip-breaking groove (66; 166, 176; 266) and, as viewed at the outlet opening (32) along a plane perpendicular to the direction of the cutting movement (44), the cross section of the through hole (62; 162, 172; 262) projects at least 20% above the chip-breaking groove (66; 166, 176; 266) and contacts the cutting edge (64; 164, 174; 264).

4. 4. The method according to claim 1, wherein the mould body (74, 274, 374) is positioned in the cavity (54, 354) such that the longitudinal axis (34, 268) of the resulting through hole (62; 162, 172; 262) is oriented at an angle of 45°-90°, in particular at an angle of 60°-90°, relative to the direction of the cutting movement (44).

5. 5. The method according to claim 1, wherein the die body (74, 274, 374) is positioned in the cavity (54, 354) so ​​that the resulting through hole (62; 162, 172; 262) is oriented at an angle between 0° and 45°, in particular parallel, to a main extension direction of a shaft (68, 170, 270, 368) of the pressed article (60, 160, 260, 360).

6. 6. The method according to claim 1, wherein the feed direction (110, 310) of the mould body (74, 274, 374) is perpendicular to the main pressing direction (118) of the cavity (54, 354).

7. 7. The method of claim 1, wherein the die body (74, 274, 374) is disposed in the cavity (54, 354) in a neutral phase of the pressed article (60, 160, 260, 360) or at least adjacent to the neutral phase of the pressed article (60, 160, 260, 360).

8. 8. The method of claim 1, wherein the tip space (42) of the pressed article (60, 160, 260, 360) is at least partially defined by the operating surface (100, 300) of the moveable die part (92, 292, 404).

9. 9. The method of any one of claims 1 to 8, wherein the tip space (42) of the pressed article (60, 160, 260, 360) is at least partially defined by another movable die part (394).

10. 10. The method according to any one of claims 1 to 9, wherein at least the chip spaces (42) and the through holes (62; 162, 172; 262) are formed in the die (52, 352) with little or no post-processing with respect to their geometrical shape.

11. 11. The method according to claim 1, wherein the die body (74, 274, 374) is positioned in the cavity (54, 354) such that in the pressing article (60, 160, 260, 360) the outlet openings (32) of the through holes (62; 162; 172; 262) facing the tip space (42) are arranged on a surface (40) of the pressing article (60, 160, 260, 360), the outlet openings (32) being oriented at an angle between 0° and 45°, in particular at an angle between 0° and 30°, relative to the main pressing direction (118).

12. 12. The method of claim 1, wherein the mold part (92, 292, 404) and the mold body (74, 274, 374) are positioned relative to each other to intimately contact the powder prior to filling the cavity (54, 354) with hard metal powder (86).

13. 12. The method of claim 1, wherein the die part (92, 292, 404) and the die body (74, 274, 374) are positioned relative to each other to bring the powder into intimate contact after filling the cavity (54, 354) with the hard metal powder (86).

14. 14. The method according to any one of the preceding claims, further comprising actively moving at least the die part (92, 292, 404) or the die body (74, 274, 374) after filling the cavity (54, 354) with hard metal powder.

15. 15. The method of claim 1, wherein the step of providing the mould parts (92, 292, 404) and the mould body (74, 274, 374) comprises engaging a stationary recess (98, 398) in the mould parts (92, 292, 404) with a front face (78, 278) of the mould body (74, 274, 374), the stationary recess (98, 398) preferably being sealed to provide a powder tight seal.

16. 16. The method of claim 15, wherein the mold part (92, 292, 404) has a closure (106) for the stationary recess (98, 398), the closure sealing the stationary recess (98, 398) in a powder-tight manner when the mold body (74, 274, 374) is not engaged.

17. 17. The method according to claim 16, wherein the closure is arranged as a flexible closure (106) which is specifically moved and / or compressed during engagement of the mould body (74, 274, 374).

18. 18. The method of claim 1, wherein the step of providing the mold part (92, 292, 404) and the mold body (74, 274, 374) comprises positioning a front surface (78, 278) of the mold body (74, 274, 374) against the abutment area (124, 324) on the mold part (92, 292, 404) in intimate powder contact.

19. 19. The method according to claim 18, wherein the mould body (74, 274, 374) assumes at least one abutment position along its feed direction (110, 310), in which the mould part (92, 292, 404) is moved against a front surface (78, 278) of the mould body (74, 274, 374) during its movement in its feed direction (114, 314) to displace any powder particles.

20. 20. The method according to any one of the preceding claims, wherein the feed direction (114, 314) of the die parts (92, 292, 404) is parallel to a main pressing direction (118).

21. 20. The method according to any one of the preceding claims, characterized in that the feed direction (114, 314) of the die parts (92, 292, 404) is perpendicular to the main pressing direction (118), in particular perpendicular to the feed direction (110, 310) of the die body (74, 274, 374).

22. 22. The method of any one of claims 1 to 21, wherein the die part (92, 292, 404) is a punch (94) and is at least partially responsible for compacting the hard metal powder (86).

23. 23. The method of any one of claims 1 to 22, wherein the mold part (292) is a slider (294).

24. 24. The method according to claim 1, wherein besides the die part (92, 292, 404) at least one other die part (80, 102) arranged as a punch (82, 104) is used, the other die part (80, 102) arranged as a punch (82, 104) preferably having a feed direction (112, 116; 412, 414) which is parallel or perpendicular to the feed direction (114, 314) of the die part (92, 292, 404).

25. The die part (92, 292, 404) is arranged as a pre-press punch (94, 294) and the further die part (80, 102) is arranged as a punch (82, 104) in a parallel feed direction (112), and the pre-press punch (94, 294) and the die body (74, 274, 374) are moved towards each other via hard metal powder (86) introduced into the cavity (54, 354), so that at least a part of the hard metal powder (86) is compressed by the pre-press punch (94, 294).

25. The method according to claim 24, further comprising compressing the powders intimately relative to one another, the punch (82, 104) subsequently moving parallel to the pre-press punch (94, 294) but with a larger compression stroke, preferably the punch (82, 104) forming a significant part of the area in the pressed article (60, 160, 260, 360) which closes the through hole (62; 162, 172; 262) along its longitudinal extension.

26. 1. An apparatus for producing hard metal pressed articles, in particular sintered green parts for cutting tools, comprising: a die forming a cavity (54, 354) for producing a pressed article (60, 160, 260, 360) having at least one cutting edge (64; 164, 174; 264) and at least one chip-crushing groove (66; 166, 176; 266) associated with a chip space (42), the die comprising: at least one movable die part (92, 292, 404), in particular a punch or slider, which at least partially defines the shape of a press article (60, 160, 260, 360) having an operating surface (100, 300) and which can be fed in a first feed direction (114, 314); a movable mold body (74, 274, 374) having a rod-shaped operating portion (76, 276, 376) for forming a through hole, the rod-shaped operating portion (76, 276, 376) having in particular a front surface (78, 278) and capable of being fed in a second feed direction (110, 310); the first feed direction (114, 314) and the second feed direction (110, 310) are inclined at least 45° to each other; The cavity (54, 354) is filled with hard metal powder (86); the apparatus has at least one pressing direction for compressing hard metal powder (86) introduced into the cavity (54, 354); The die part (92, 292, 404) and the die body (74, 274, 374) are movable and feedable, and the die body (74, 274, 374) in a cavity (54, 354) having an operating portion (76, 276, 376) is positioned so that powder becomes dense in a contact area (124, 324) on the first die part (92, 292, 404), thereby forming a through hole (62, 162, 172, 262).

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