Manufacturing a hard-metal pressed article
11241737 · 2022-02-08
Assignee
Inventors
Cpc classification
B30B15/026
PERFORMING OPERATIONS; TRANSPORTING
B22F2005/001
PERFORMING OPERATIONS; TRANSPORTING
B30B11/007
PERFORMING OPERATIONS; TRANSPORTING
B22F3/16
PERFORMING OPERATIONS; TRANSPORTING
C22C29/00
CHEMISTRY; METALLURGY
B30B15/304
PERFORMING OPERATIONS; TRANSPORTING
B30B15/022
PERFORMING OPERATIONS; TRANSPORTING
B22F2003/033
PERFORMING OPERATIONS; TRANSPORTING
International classification
B22F3/03
PERFORMING OPERATIONS; TRANSPORTING
B30B15/02
PERFORMING OPERATIONS; TRANSPORTING
B22F3/16
PERFORMING OPERATIONS; TRANSPORTING
B30B11/00
PERFORMING OPERATIONS; TRANSPORTING
C22C29/00
CHEMISTRY; METALLURGY
Abstract
Manufacturing a hard-metal pressed article includes providing a multi-part die, feeding at least one frontal mold part, feeding at least one transverse mold and locking the at least one frontal mold part and the at least one transverse mold part to define a cavity for the article. Feed directions of the at least one frontal mold part and the at least one transverse mold part are inclined. The at least one frontal mold part and the at least one transverse mold part define surfaces of the article. The resulting cavity includes at least one opening through which a punch is insertable. Next, a filling shoe is fed above an opening of the cavity and fills the cavity with a powder, and the powder is compressed with at least one punch. The feeding of the transverse mold part takes place along a feed direction that is parallel to the main pressing direction.
Claims
1. A method for near-net-shape manufacture of a hard-metal pressed article, the method comprising: feeding at least one frontal mold part that is movable in a first plane, comprising feeding a first frontal mold part and a second frontal mold part of a multi-part die, feeding at least one transverse mold part that is movable in a second plane, comprising feeding an upper transverse mold part and a lower transverse mold part, providing a locking device for securing the transverse mold parts and frontal mold parts in a closed position to form a peripheral contour of a hard-metal pressed article, the locking device laterally securing the upper transverse mold part and the lower transverse mold part, and the first frontal mold part and the second frontal mold part, and locking the at least one frontal mold part and the at least one transverse mold part with the locking device to define a cavity which defines the shape of the hard-metal pressed article, wherein feed directions of the at least one frontal mold part and the at least one transverse mold part are inclined to one another, wherein the at least one frontal mold part and the at least one transverse mold part define surfaces of the hard-metal pressed article, and wherein the cavity comprises at least one opening through which a punch is insertable, and wherein the at least one opening is defined by the at least one frontal mold part and the at least one transverse mold part, feeding a filling shoe above the at least one opening in the cavity and filling the cavity with a hard-metal powder, and compressing the hard-metal powder with at least one punch that is movable parallel to a main pressing direction, the step of compressing the hard metal powder comprising feeding an upper punch and a lower punch to form the hard-metal pressed article, wherein the at least one transverse mold part is fed along a feed direction that is parallel to the main pressing direction.
2. The method as claimed in claim 1, wherein the at least one frontal mold part is fed in a horizontal plane, wherein the at least one transverse mold part is fed in a vertical plane, and wherein the feed directions of the at least one frontal mold part and the at least one transverse mold part are oriented perpendicular to each other.
3. The method as claimed in claim 1, wherein the at least one frontal mold part is fed laterally and provided with a frontal shaping portion defining a first portion of the shape of the hard-metal pressed article, and wherein the at least one transverse mold part is fed vertically and provided with a lateral shaping portion defining a second portion of the shape of the hard-metal pressed article.
4. The method as claimed in claim 1, wherein the at least one punch is fed vertically and provided with a frontal shaping portion that defines a portion of the shape of the hard-metal pressed article.
5. The method as claimed in claim 1, wherein the upper punch and the upper transverse mold part are associated with a first side, wherein the lower punch and the lower transverse mold part are associated with a second side, wherein the upper punch and the upper transverse mold part are fed at least partially via common guide elements, and wherein the lower punch and the lower transverse mold part are fed at least partially via common guide elements.
6. The method as claimed in claim 1, further comprising a demolding step after the step of compressing the hard-metal powder, including opening the multi-part die, comprising extending the at least one frontal mold part, extending the at least one transverse mold part, and extending the at least one punch, wherein the at least one transverse mold part is moved parallel to the main pressing direction to release at least a portion of the hard-metal pressed article.
7. The method as claimed in claim 1, wherein the step of feeding a filling shoe comprises laterally feeding the filling shoe to an upper opening of the cavity, wherein the filling shoe is guided into a clearance space provided by the upper punch that is spaced from the cavity.
8. The method as claimed in claim 1, wherein the locking device secures the transverse mold parts and frontal mold parts by encircling the transverse mold parts and frontal mold parts.
9. The method as claimed in claim 5, wherein the upper punch and the lower transverse mold part together define a first cutting edge, and wherein the lower punch and the upper transverse mold part together define a second cutting edge.
10. The method as claimed in claim 9, wherein the first cutting edge is associated with a first rake face and a first relief face, wherein the second cutting edge is associated with a second rake face and a second relief face, and wherein the first rake face is formed by the upper punch, the second rake face by the lower punch, the first relief face by the lower transverse mold part, and the second relief face by the upper transverse mold part.
11. A method for the manufacture of a hard-metal cutting tool, comprising: manufacturing a hard-metal pressed article in accordance with the method as claimed in claim 1, transferring the article from a pressing plant to a sintering plant, and sintering the hard metal pressed article to produce the hard-metal cutting tool.
12. A method for near-net-shape manufacture of a hard-metal pressed article comprising: feeding at least one frontal mold part that is movable in a horizontal plane, comprising feeding a first frontal mold part and a second frontal mold part of a multi-part die, feeding at least one transverse mold part that is movable in a vertical plane, comprising feeding an upper transverse mold part and a lower transverse mold part, providing a locking device for securing the transverse mold parts and frontal mold parts in a closed position to form a peripheral contour of a hard-metal pressed article, the locking device laterally securing the upper transverse mold part and the lower transverse mold part, and the first frontal mold part and the second frontal mold part, and locking the at least one frontal mold part and the at least one transverse mold part with the locking device to define a cavity which defines the shape of the hard-metal pressed article, wherein feed directions of the at least one frontal mold part and the at least one transverse mold part are perpendicular to one another, wherein the at least one frontal mold part and the at least one transverse mold part define surfaces of the hard-metal pressed article, and wherein the cavity comprises at least one opening through which a punch is insertable; and wherein the at least one opening is defined by the at least one frontal mold part and the at least one transverse mold part feeding a filling shoe above the at least one opening in the cavity and filling the cavity with a hard-metal powder, and compressing the hard-metal powder with at least one punch that is movable parallel to a main pressing direction, the step of compressing the hard-metal powder comprising feeding an upper punch and a lower punch to form the hard-metal pressed article, each having a vertical reed direction, wherein the at least one transverse mold part is fed along a feed direction that is parallel to the main pressing direction.
13. A method for the manufacture of a hard-metal pressed blank for indexable, cutters that are arranged as two-edge cutters comprising two opposite edges, the method comprising: feeding at least one frontal mold part that is movable in a horizontal plane, comprising feeding a first frontal mold part and a second frontal mold part of a multi-part die, feeding at least one transverse mold part that is movable in a vertical plane, comprising feeding an upper transverse mold part and a lower transverse mold part, providing a locking device for securing the transverse mold parts and frontal mold parts in a closed position to form a peripheral contour of a hard-metal pressed blank, wherein the locking device laterally encloses the upper transverse mold part, the lower transverse mold part, the first frontal mold part, and the second frontal mold part, and locking the at least one frontal mold part and the at least one transverse mold part with the locking device to define a cavity which defines the shape of the hard-metal pressed blank, wherein feed directions of the at least one frontal mold part and the at least one transverse mold part are perpendicular to one another, wherein the at least one frontal mold part and the at least one transverse mold part define surfaces of the hard-metal pressed blank, and wherein the cavity comprises at least one opening through which a punch is insertable, feeding a filling shoe above the at least one opening in the cavity and filling the cavity with a hard-metal powder, and compressing the hard-metal powder with at least one punch that is movable parallel to a main pressing direction, the step of compressing the hard-metal powder comprising feeding an upper punch and a lower punch, each having a vertical feed direction to form the hard-metal pressed blank, wherein the at least one transverse mold part is fed along a feed direction that is parallel to the main pressing direction, and wherein the upper punch and the lower transverse mold part together define a first cutting edge, and wherein the lower punch and the upper transverse mold part together define a second cutting edge of the hard-metal pressed blank.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Further features and advantages of the disclosure are disclosed by the following description of a plurality of exemplary embodiments, with reference to the drawings, wherein:
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DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
(16) With reference to
(17) The pressed article 10 serves primarily as an illustrative example for a large number and variety of other pressed articles, the manufacture of which can be performed in accordance with aspects described herein, relating to the device and/or the method.
(18) At least in principle, the shape of the pressed article 10 can also be obtained using alternative methods and devices, such as injection molding or alternative pressing methods for the manufacture of raw parts (also referred to as intermediates or blanks). Nevertheless, each of these alternative approaches may have certain disadvantages, depending on the actual circumstances, which are at least partially overcome within the context of the present disclosure. When a pressed article that is at least similarly shaped is produced using conventional pressing methods, post-processing is indispensable. Generally, a rough contour is obtained by pressing or injection molding, which must be extensively machined, especially by grinding.
(19) The method and the device according to the present disclosure enable, according to at least some embodiments, a significant reduction and/or even elimination of such post-processing by means of grinding. In other words, it can be manufactured close to the final contour (net shape) and with only little post-processing and/or no post-processing.
(20) In combination, a Cartesian coordinate system X, Y, Z can be derived from
(21) The pressed article 10 comprises a main body 12, which substantially extends in a longitudinal direction X, cf. also
(22) It can be seen for instance from the illustration according to
(23) As it is generally known, the cutter edges 16 include a rake face 20 and a relief face 22, which includes a tapering. The cutter edges 16 are designed with point symmetry with respect to a center of the pressed article 10. This allows a simple change between the two cutter edges 16 by a 180° rotation of the cutting insert.
(24) In certain embodiments, the pressed article 10 is oriented in a cavity of a pressing device in such a way that the Z axis coincides with a main pressing direction. Accordingly, special measures must be taken to ensure that the pressed article 10 can be demolded with the smallest possible number of mold parts and punches within the context of manufacturing approaches that come as close to the final contour as possible, and that requires little post-processing or no post-processing at all.
(25) According to the view orientation in
(26) In the case of an exclusively lateral demolding, in which for instance two sliders are provided, which are movable along the Y direction, each slider would basically form the contour or silhouette shown in
(27) Therefore, in the context of the present disclosure, it is proposed to demold the pressed article 10 by an interaction of frontal mold parts and transverse mold parts.
(28) In
(29) In
(30) An area designated by 34 is defined by the mold partitions 26, 28 and describes the portion which can be demolded by a punch which is movable in the main pressing direction Z. By way of example, the surface 34 involves the rake surface 20 including the ridge-shaped elevation 36.
(31) The ridge-shaped elevation 36 is arranged to be obtuse or obtuse-angled in the Z direction. Accordingly, the elevation 36 can be shaped by the geometry of the punches without significant, disadvantageous reductions in the wall thickness of the punches.
(32) In certain embodiments, on the basis of the mold partitions 24, 26, 28 and the progression of the press density that is caused by the main pressing axis Z, at least in the raw state of the pressed article 10, it is possible to draw conclusions about the type of manufacturing and the design of a die used for manufacturing. In addition, in certain embodiments, the type of manufacturing and the design of a die used for manufacturing may also be derived even in the sintered state of the workpiece from the mold partitions 24, 26, 28.
(33) With reference to
(34) For illustrative purposes, the following figures show simplified representations of the pressed article 10 and components of the device 40. The orientation of the pressed article 10 in the device 40 is elucidated by the coordinate system X, Y, Z, which is shown in at least some of the figures described hereinafter.
(35) In certain embodiments, the device 40 is used for processing hard-metal powder for the manufacture of hard-metal pressed articles for the powder metallurgical manufacture of cutting inserts, inserts etc.
(36) The device comprises a bed 42 which can be part of or at least coupled to a frame. Furthermore, a die 46 is provided, which forms a cavity 48, cf. also
(37) The die 46 comprises a first frontal mold part 54 and a second frontal mold part 56, which are mounted on the bed 42 offset from one another in the transverse direction Y, for instance. Accordingly, the first frontal mold part 54 is mounted on a horizontal guide 58. The second frontal mold part 56 is mounted on a horizontal guide 60. The horizontal guides 58, 60 are arranged as profile guides, for instance.
(38) Further, the die 46 comprises so-called transverse mold parts 64, 66. The exemplary embodiment illustrated in
(39) A vertical guide 68 is provided for the movement of the first transverse mold part 64. A vertical guide 70 is provided for moving the second transverse mold part 66. Via the vertical guides 68, 70, the transverse mold parts 64, 66 are coupled to the bed 42.
(40) The frontal mold parts 54, 56 and the transverse mold parts 64, 66 together define parts of the die 46 which are not actively moved during the actual pressing process. The mold parts 54, 56, 64, 66 are opened to demold the pressed article 10. Punches 74, 76 can be retracted for the molding the pressed article 10 through openings 50 in the (closed) cavity 48, which is defined by the mold parts 54, 56, 64, 66. In the exemplary embodiment of the device 40 illustrated in
(41) The device 40 comprises punches 74, 76 that are assigned to a punch group or punch unit 82. The first punch 74 may also be referred to as the upper punch. The second punch 76 may also be referred to as the lower punch. Accordingly, the first punch 74 is assigned to an upper side of the device 40 or the die 46. The second punch 76 is assigned to a bottom side of the device 40 or the die 46. In the pressing of hard-metal pressed articles to provide blanks to be sintered, generally two punches 74, 76 are used, which are arranged opposite to each other in the height direction or vertical direction Z and offset from each other, and which may approach one another in order to compress and to bring the hard-metal powder that is accommodated in the cavity 48 into shape.
(42) A first vertical guide 78 is provided for the movement of the first punch 74. A second vertical guide 80 is provided to move the second punch 76. According to at least some exemplary embodiments, the vertical guide 80 of the punch 74 is directly or mediately coupled with the first transverse mold part 64. The vertical guide 80 of the second punch 76 is, for example, directly or mediately coupled with the second transverse mold part 66.
(43) The horizontal guides 58, 60 for the frontal mold parts 54, 56 comprise a guide profile 88, which may also be referred to as the guide base. A corresponding counter profile is formed on the frontal mold parts 54, 56.
(44) The vertical guides 68, 70 for the transverse mold parts 64, 66 also include a guide profile 90, which is arranged on the bed 42. The transverse mold parts 64, 66 can contact the guide profile 90 via a corresponding counter profile.
(45) The vertical guides 78, 80 for the punches 74, 76 of the punch unit 82 comprise guide profiles 92 and 94. At least in accordance with the exemplary embodiment illustrated in
(46) In
(47) The frontal parts 54, 56 can be fed along a horizontal plane defined by the axes X, Y. The transverse mold parts 64, 66 can be fed along a vertical plane which is oriented parallel to the Z axis and/or which coincides with the Z axis. In other words, the frontal mold parts 54, 56 can be fed laterally. The horizontal fittings 64, 66 can be fed vertically (from above and/or from the bottom). The punches 74, 76 may also be fed vertically (from above and/or from the bottom). The first transverse mold part 64 and the first punch 74 have parallel feed directions 104, 108. The second transverse mold 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 each other and, for example, approximately perpendicular to the other feed directions 104, 106, 108, 110. In the event that several frontal mold parts are used, further (lateral) feed directions may be provided, which do not necessarily have to be parallel to any other (lateral) feed directions.
(48) A frontal shaping portion 116 is formed on the first frontal mold part 54. A frontal shaping portion 118 is formed on the second frontal mold part 56. A lateral shaping portion 120 is formed on the first transversal mold part 64. A lateral shaping portion 122 is formed on the second transverse mold part 66. A frontal shaping portion 124 is formed on the first punch 74. A frontal shaping portion 126 is formed on the second punch 76.
(49) In the context of the present disclosure, a frontal shaping portion is to be understood as a portion of the respective mold part which defines the cavity 48 and/or the shape of the article 10 to be produced, and which extends substantially transversely or perpendicularly to the feed direction of the used mold part. On the other hand, a lateral shaping portion is a section of the mold part which defines the cavity 48 or the shape of the article 10 to be produced, and which extends approximately parallel or slightly inclined to the respective feed direction of the mold part.
(50) Together, the shaping portions 116, 118, 120, 122, 124, 126 define the shape of the pressed article 10 to be produced, which results from the design of the cavity 48. For an illustration of the cavity 48, reference is also made to the detailed views of
(51) The frontal mold parts 54, 56 can be fed laterally, refer to the feed directions 100, 102. The shaping portions 116, 118 of the frontal mold parts 54, 56 form lateral sections of the cavity 48 and the pressed article 10 to be formed. In certain embodiments, the lateral surface 30 of the pressed article 10 can be produced with the shaping portions 116, 118, cf. also
(52) The punches 74, 76 are also provided with “frontal” shaping portions 122, 124, by means of which the respective surface 34 (cf.
(53) It can be clearly different for the transverse mold parts 64, 66, which can be fed along the feed directions 104, 106. The “lateral” shaping portions 120, 122 define portions and/or surfaces 32 of the pressed article 10 to be formed. The surfaces 32 may also be referred to as lateral surfaces, since they extend substantially perpendicular and/or only slightly inclined with respect to a horizontal plane that 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 mold parts 64, 66 are fed vertically, for example from above or from below, although they form “lateral” sections or surfaces 32 of the pressed article 10. Thus, the feed direction and operating direction of the shaping portion are oriented approximately transversely to each other.
(54) This enables a vertical, opposite demolding of the surfaces 32, which define the relief faces 22 of the cutting edges 16. Lateral demolding (along the X-direction) is not possible, since in this case the constriction 14 of the main body 12 would form an undercut area. Lateral demolding in the Y-direction would be disadvantageous, as then a mold partition transverse or perpendicular to the course of the cutting edge 18 would be necessary.
(55) The interaction of the shaping portions 116, 118, 120, 122, 124 can be seen for instance in the enlarged illustration in
(56) With reference to
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(58) By way of example, the filling shoe 134 is placed above the opening 50, through which the (upper) punch 74 can retract. Accordingly, at least the punch 74 of the punch unit 82 is in the filling configuration spaced away from the die 46. This is elucidated in the views of
(59) The (upper) transverse mold part 64 is also provided with a corresponding recess so that the filling shoe 134 can be fed to the cavity 48. Generally, the filling of cavity 48 with the hard-metal powder is supported by gravity.
(60) In certain embodiments, the punch 74 is guided on a guide arm 138, especially on a guide profile 92 thereof (see
(61) Similarly, a guide arm 140 may also be designed for the (lower) transverse mold part 66, on which the (lower) punch 76 is guided via a corresponding guide profile 92.
(62) The federal guide profiles 94 of the transverse mold parts 64, 66 (see again
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(65) For illustrative reasons,
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(68) A further refinement may involve forming at the bed 42 abutment surfaces 144, 146, which may also be referred to as chamfers. From the sectional view in
(69) For illustrative purposes, the pressed article 10 is not shown in the supplementary detailed illustration according to
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(72) By way of example, the locking device 150 can comprise at least one holder 152, 154. The locking device 150 can support and fix the mold parts 54, 56, 64, 66 positively, non-positively or in any other suitable way, at least during the pressing process.