Die Ejector

Abstract

A die-ejector (2) comprising a chamber (4) with a cover plate (40) having a passageway, a plurality of plates (56) arranged inside the chamber (4) and reciprocally movable between an initial position (58) and an operating position (60), respectively, intended to interact with the carrier to support the removal of the dies from the carrier, and a drive member (100) for moving the plates (56) to be moved from the operating position towards the initial position. The die-ejector (2) further comprises a magnet (20) and a spring system, respectively, which interacts with anchor sections (74) of the plates (56) and exerts on the plates (54) an attraction force (F′) or an impact force, respectively, directed towards the operating position, and a stop member (78) for stopping the movement of the plates (56) in the operating position, the plates abutting the stop member (78) in the operating position.

Claims

1. Die ejector (2) comprising a chamber (4) which can be subjected to a vacuum, said chamber having a cover plate (40) which has a passageway, wherein the surface of said cover plate facing away from the chamber (4) forms a supporting surface (52) for a carrier provided with dies, a plurality of plates (56) which are arranged in the interior of the chamber (4), which are movable back and forth between an initial position (58) and an operating position (60), respectively, said plates having a drive recess (70), and wherein the plate plane of said plates is aligned transversely to the cover plate (40) and wherein the edge portion of said plates that extends at least approximately perpendicular to the direction of movement and faces towards the cover plate forms an impact edge (77) which is intended to interact with the support in order to support the removal of the dies from the support, the initial position (58) being set back towards the interior of the chamber (4) with respect to the operating position (60), and a drive element (100) which can be driven by a motor and penetrates the drive recesses (70), the drive recesses (70) each having a drive area (102) which is designed such that the drive element (100) interacts with the drive area (102) in order to move the plates (56) to be moved from the operating position (60) to the initial position (58), characterised in that a magnet (20) or a spring system interacting with the anchor sections (74) of the plates (56) exerts on the plates (56) an attraction force (F′) and/or an impact force or a pull force directed in the direction of the operating position (60), and a stop element (78) stops the movement of the plates (56) in the operating position (60), the plates (56) abutting against the stop element (78) in the operating position (60).

2. Die-ejector (2) according to claim 1, characterized in that the stop element (78) also stops the movement of the plates (56) in their initial position (58).

3. Die-ejector (2) according to claim 1, characterized in that the stop element (78) is designed as a preferably flattened bolt and penetrates a stop recess (70) of the plates (56).

4. Die-ejector (2) according to claim 1, characterized in that in the case of a magnet (20) there is always an air gap between the magnet (20) and the plates (56).

5. Die-ejector (2) according to claim 1, characterized in that the plates (56) are T-shaped and the crossbeam of the T-shaped plate forms the anchor section (74), the side of the crossbeam facing the magnet (20) in the case of a magnet (20) or the side of the crossbeam facing the spring system in the case of a spring system running at least approximately parallel to the surface of the magnet (20) or the surface of the spring system.

6. Die-ejector (2) according to claim 1, characterized in that the drive recesses (70) each have a further drive area (104) which is designed such that the drive element (100) interacts with the further drive area (104) in order to move the plates (56) to be moved from the initial position (58) in the direction of the operating position (60), in that a further magnet (10) is assigned to the initial position (58) in the case of a magnet (20), and the anchor section (74) is located between the magnet (20) and the further magnet (10), and in that the drive element (100) moves the anchor section (74) of the plates (56) to be moved in each case from the initial position (58) in the direction of the operating position (60) away from the further magnet (10) in the direction of the magnet (20), at least until the attraction force (F′) of the magnet (20) is greater than that (F) of the further magnet (10), and the plates (56) to be moved then move into the operating position (60) under the attraction force (F′) of the magnet (20), and vice versa for the movement of the plates (56) from the operating position (60) in the direction of the initial position (58) away from the magnet (20) towards the further magnet (10).

7. Die-ejector (2) according to claim 6, characterized in that the driving element (100) comprises a camshaft (100) which is rotatably driven about its axis by means of the engine, wherein the cams (106) of said camshaft are intended to interact with the drive area (102) and the further drive area (104) of the plates (56) to be moved.

8. Die-ejector (2) according to claim 7, characterized in that the cams (106) are arranged, in the circumferential direction of the camshaft (100), in such a way that the plates (56) are moved in a predetermined order between the initial position (58) and the operating position (60) and vice versa.

9. Die-ejector (2) according to claim 7, characterized in that the cams (106) have an involute shape.

10. Die-ejector (2) according to claim 7, characterized in that the drive area (102) and the further drive area (104) are each formed by a shoulder (102, 104) formed on the respective plate (56) which shoulder extends transversely to the direction of movement of the plate (56), and the cam (106) assigned to the respective plate (56) abuts the respective shoulder when the camshaft (100) is rotated.

11. Die-ejector (2) according to claim 1, characterized in that the drive element (100) comprises a shaft (100) which is driven rotatably about its axis by means of the motor, wherein the outer circumference of said shaft forms control cams (122) which lie in planes extending perpendicular to the axis, and the shaft (100) is turned for transferring the plates (56) from the operating position (60) into the initial position (58) from an operating rotary position, in which the plates (56) are in the operating position, to an initial rotary position, in which the plates (56) are in the initial position, wherein in each case a control cam (122) interacts with the drive area (102) of an associated plate or plates in order to push or to pull the plate or plates, in the case of a magnet, against the gravitational force (F′) of the magnet (20) or, in the case of a spring system, against the impact force of the spring system in the direction of the initial position (58) as a result of the increase in the radius of the control cam (122).

12. Die-ejector (2) according to claim 11, characterized in that in the operating rotary position there is in each case a gap between the drive area (102) of the plate and the control cam (122).

13. Die-ejector (2) according to claim 11, characterized in that the shaft (100) is driven back and forth between the initial rotary position and the operating rotary position.

14. Die-ejector (2) according to claim 13, characterized in that an end face (128) of the shaft has a recess (130) which is central to the axis, circular-arc-shaped and groove-shaped, for receiving a pin (131) which is arranged in a fixed position relative to the chamber, one end of the recess (130) forms a first rotational stop (134) of the shaft assigned to the operating rotary position, and the other end forms a second rotational stop (138) of the shaft assigned to the initial rotary position.

15. Die-ejector (2) according to claim 11, characterized in that the control cams (122) are arranged such that the plates (56) are moved in a predetermined order between the initial position (58) and the operating position (60) and vice versa.

16. Die-ejector (2) according to claim 1, characterized in that the plates (56) are designed in several parts, preferably in two parts with a base plate (68) having the anchor section (74) and the drive recess (70) and a support plate (72) which can be placed on the base plate (68) and forms the impact edge (77), and the stop element (78) interacts with the support plate (72).

17. Die-ejector (2) according to claim 1, characterized in that, in the case of a spring system, the spring system is arranged at the bottom of the chamber in order to move the plates via its impact force from the initial position in the direction of the operating position and to hold them in the operating position.

18. Die-ejector (2) according to claim 1, characterized in that, in the case of a spring system, the spring system is formed as a plurality of spring strips arranged at the bottom of the chamber, in each case one spring strip being assigned to a plate and interacting with a plate.

19. Die-ejector (2) according to claim 1, characterised in that, in the case of a spring system, the spring system is arranged on the side of the chamber opposite the bottom and serves to move the plates from the initial position in the direction of the operating position via its attraction force and to hold them in the operating position.

20. Die-ejector (2) according to claim 1, characterized in that in the case of a spring system, the spring system comprises comb-like flexural spring tongues projecting from a mounting plate, each interacting with a plate.

21. Die-ejector (2) according to claim 1, characterized in that in the case of a spring system, the spring system comprises a compression spring or a tension spring or a combination thereof, in order to exert a force of attraction in the direction of the operating position, preferably on the plates.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0099] Further advantages and features of the invention can be seen in the following description of an exemplary embodiment, which is explained using the enclosed figures, in which:

[0100] FIG. 1 shows a cross-section in the longitudinal direction of a first embodiment of the die-ejector according to the invention, represented in perspective view;

[0101] FIG. 2 shows a perspective view of the camshaft installed in the die-ejector as shown in FIG. 1;

[0102] FIG. 3 shows a cross-section in the longitudinal direction of a part of an second embodiment of the die-ejector according to the invention; and

[0103] FIG. 4 shows a perspective view of the shaft built into the die-ejector as shown in FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0104] In a first embodiment, the die-ejector 2 as shown in FIG. 1 comprises a chamber 4 which can be subjected to vacuum and which is formed by a multi-part housing 6 defining a longitudinal axis L. The chamber 6 is formed by a multi-part housing 6 defining a longitudinal axis L. The housing 6 comprises a parallelepipedal housing part 8, which comprises a housing cover 16, an airtight base 12 extending perpendicular to the longitudinal axis L, two side walls 14 or 14′, an end wall (not shown) and a rear wall (not shown). The housing cover 16 is attached in an airtight manner to the housing part 8 and has a circular opening 24 from which a tube part 22 extending along the longitudinal axis L protrudes.

[0105] Furthermore, the housing 6 comprises a flange 36 having a circular cylindrical passageway, which is pushed onto the tube part 22. In a first end area of the flange facing the housing cover 16, the passageway has a diameter which is slightly larger than the outer diameter of the tube part 22. In the first end area of the flange, the flange 36 lies in an airtight manner against the tube part 22 via an O-ring 34 arranged in the flange 36. In a second end area of the flange remote from the housing cover 16, the passageway has a larger diameter than the outer diameter of the tube portion 22 to form a circumferential recess 38 intended to receive a circular cylindrical plate support 30.

[0106] The housing 6 also comprises the circular cylindrical plate carrier 30, on which a cover plate 40 is airtight and replaceable via a further O-ring 42. The plate carrier 30 is pushed onto the tube part 22, pushed into the circumferential recess 38 and in the assembled state lies airtight against the tube part 22 via a further O-ring 44 arranged in the flange 36.

[0107] The chamber 4 has a vacuum port 46 for connection to a vacuum source. The cover plate 40 has a passageway 50 and the surface of the cover plate 40 facing away from the chamber 4 forms a support surface 52 for a carrier provided with dies, which carrier is not shown in FIG. 1. The support surface 52 is perpendicular to the longitudinal axis L of the housing 6 of the die-ejector 2. In addition, the cover plate 40 has a plurality of through holes 54 arranged around the passageway 50 which serve to suck in the carrier when vacuum is applied to chamber 4, so that the carrier is held firmly on the cover plate 40 during the die detachment and removal.

[0108] The die-ejector 2 further comprises a plurality of plates 56 arranged inside the chamber 4, parallel to each other and parallel to the longitudinal axis L of the housing 6, which are movable back and forth in a direction of movement B in the direction of the longitudinal axis L, respectively between an initial position 58 and an operating position 60. The plate plane of the plates 56 is perpendicular to the cover plate 40 and to the side walls 14 and 14′ respectively. Due to the design, the plate plane is therefore parallel to the longitudinal axis L.

[0109] The housing cover 16 has on its side facing the inside of the housing part 8 two installation recesses 18 and 18′, respectively, which run parallel to the side walls and are arranged symmetrically with respect to a longitudinal plane of symmetry of the plates 4 encompassing the longitudinal axis L. A multi-part magnet 20 is arranged in each installation recess. A further multi-part magnet 10 is arranged on the bottom.

[0110] The magnet 20 is assigned to the operating position 60 and the magnet 10 is assigned to the initial position 58. The magnet 20 and the further magnet 10 extend perpendicular to the plate plane and are permanently polarized in opposite polarization directions, marked by S-N and N-S, respectively, which are at least parallel to the direction of movement B. Thus, the magnetic field of the magnet and of the further magnet 20 and 10, respectively, exert an attraction force F and F′, respectively, on the plates 56, said force being substantially parallel to the direction of movement B.

[0111] The plates 56 are formed in two parts and each comprise a base plate 68, which contains a drive recess 70, and a support plate 72, which is placed on the base plate 68 and is connected to the base plate 68 by a mechanical connection 73. The drive recesses of all base plates 68 are of the same design.

[0112] The base plates 68 are T-shaped and each have a longitudinal area 75, to which the support plates 72 are attached, and a crossbeam 74. The crossbeam 74 forms an anchor section 74. The side 66 of the crossbeam 74 facing the further magnet 10 runs parallel to the surface of the further magnet 10 facing the crossbeam 74 and the side 64 of the crossbeam 74 facing the magnet 20 runs parallel to the surface of the magnet 20 facing the crossbeam 74.

[0113] The edge portion of the support plates 72 facing the cover plate 40 forms an impact edge 77, which is intended to interact with the carrier in order to support the removal of the dies from the carrier. The support plates 72 each have a stop recess 76, which is penetrated by a stop element 78. The stop recesses 76 of all support plates 72 are of the same design.

[0114] The stop element 78 is designed as a flattened bolt which penetrates the stop recess 76 of the respective plates 56. The flattened bolt has a first flattened stop side 78a and a second stop side 78b parallel to the first stop side. The stop recess 76, viewed in the direction of the longitudinal axis L, extends over a length corresponding to the sum of the thickness of the stop element 78 and the stroke of the plate 56.

[0115] In addition, the base plates 74 each comprise two further stop recesses 80 formed in their anchor section, which are penetrated by a further stop element 82 formed as a bolt. The base plates 68 also each comprise a slot-like recess 84 in their longitudinal area 75, which is penetrated by a pin-shaped guide element 86. The recess 84 serves to guide the movement of the longitudinal area 75, so that the direction of movement B of the plates 56 remains parallel to the longitudinal axis L. The recesses 84 of all base plates 68 have the same design.

[0116] To guide the base plates 68, two comb-like mounting rails 90 are arranged opposite each other on the side walls 14 or 14′, the incisions of which run parallel to the direction of movement B on the side of the mounting rails 90 facing the interior of the chamber. The incisions each take up an edge area of the base plates 68 running parallel to the direction of movement and are spaced from each other in such a way that a predetermined distance between the base plates 68 is ensured when the plates 56 are moved.

[0117] For guiding the base plates 68, the tube part 22 also includes two further mounting rails 92, which are designed in the same way as the mounting rails 90 and are arranged on the opposite side.

[0118] The drive recesses 70 are penetrated by a drive element 100 and each have a drive area 102 and a further drive area 104. The drive element 100 is designed as a camshaft 100, whose tooth-like cam 106 interacts with the drive area 102 and the further drive area 104 of the plates 56 to be moved.

[0119] The drive area 102 and the further drive area 104 are each formed by a shoulder 102 or further shoulder 104 formed on the plate 56 and running transversely to the direction of movement B of the plate 56.

[0120] The camshaft 100 is driven by an engine in one direction of rotation D. The camshaft 100 shown in FIG. 2 comprises a circular cylindrical shaft part 110 with a first and a second shaft hub 112 and 114, respectively. In the assembled state, the first shaft hub 112 is arranged rotatably sliding in the end wall and the second shaft hub 114 is arranged rotatably sliding in the rear wall of the housing 6.

[0121] Between the first and second shaft hubs 112 and 114, respectively, the cams 106 protrude radially outward with respect to the shaft part 110. The cams 106 are symmetrically arranged with respect to a mirror plane running through a centrally arranged cam, said cams being perpendicular to a rotation axis H of the camshaft 100. The cams 106, seen in the unwinding of the camshaft 100, have a V-shaped arrangement, with the central cam forming the tip of the V-shape and the cams 106, seen in the direction of rotation, being offset forward.

[0122] The cams 106 each have, seen in direction of rotation D, a leading impact side 116, the shape of which is an involute shape. The impact sides 116 of two successive cams 106 show a distance A measured in the circumferential direction.

[0123] The arrangement of the plates 56 shown in FIG. 1 corresponds to a momentary embodiment of the die-ejector 2, whereby all plates 56 are in the operating position 60 and rest against the stop element 78. The impact edges 77 protrude over the supporting surface 52. When the camshaft 100 is rotated in the direction of rotation D, the impact sides 116 interact with the respective shoulder 102 to move the plates 56 to be moved from the operating position 60 in the direction of the initial position 58.

[0124] The arrangement of the impact sides 116 of the cams 106 relatively to each other determines the order of interaction of the impact sides 116 with the shoulders 102. Since the drive recesses of all base plates 68 are of the same design and the cams 106 have a V-shaped arrangement as seen in the development of the camshaft 100, the two outermost plates 56 that are symmetrical to the plate 56 assigned to the centrally arranged cam are first moved from the operating position 60 in the direction of the initial position 58. The interaction of the impact sides 116 with the shoulder 102 takes place at least until the attraction force F of the further magnet 10 is greater than the attraction force F′ of the magnet 20. The plates 56 then move under the force of attraction F of the further magnet 10 in the direction of the initial position 58.

[0125] As the camshaft 100 continues to rotate, the next impact sides 116, seen in the circumferential direction of the camshaft 100, of the two next outer plates 56, interact with the shoulder 102 of the two next outer plates 56 that are symmetrically to the plate 56 assigned to the centrally arranged cam, and move said next outer plates from the operating position 60 in the direction of the initial position 58.

[0126] Finally, the plate 56 assigned to the centrally arranged cam is moved from the operating position 60 in the direction of initial position 58.

[0127] As the camshaft 100 continues to rotate in the direction of rotation D, the impact sides 116 interact with the further shoulder 104 to move the plates 56 to be moved from the initial position 58 to the operating position 60. As already explained, mutatis mutandis, first the two outermost plates 56 are moved symmetrically to the plate 56 assigned to the centrally arranged cam 56 from the initial position 58 in the direction of the operating position 60.

[0128] In a second embodiment of the die-ejector 2 according to FIG. 3, the housing 6 is the same as in FIG. 1, but only the housing part 8 is shown with the interior of the chamber 4 and the plates 56. The same reference numbers are used in the following for parts with the same effect as for the first embodiment. In addition, the second embodiment is structured similarly to the first embodiment. The main differences are therefore described below.

[0129] The arrangement of the plates 56 shown in FIG. 3 corresponds to a momentary embodiment of the die-ejector, the plate 56 shown being in the operating position 60. The supporting surface 52 is only shown dashed in FIG. 3.

[0130] The operating position 60 of the plates 56 is assigned to the multi-part magnet 20, which is arranged in the installation recesses 18 or 18′. In contrast to the die-ejector shown in FIG. 1, the base 12 of the die-ejector shown in FIG. 3 is free of the further magnet, so no further magnet is assigned to the initial position 58. Thus, the magnetic field of the magnet 20 exerts a force of attraction F′ on the plates 56, which is directed essentially parallel to the direction of movement B. The magnetic field of the magnet 20 is thus the same as that of the plates 56. There is a gap 118 between the magnet 20 and the plate 56, which is stopped in the operating position 60 by the stop element 78 and held in operating position 60 by the magnet 20.

[0131] The drive recesses 70 are penetrated by a drive element 100 and each have a drive area 102. The drive element 100 is designed as a shaft 100, which interacts with the drive area 102 of the plates 56 to be moved at a contact point 103, and driven by a motor.

[0132] The drive area 102 is each formed by a shoulder 102 formed on the plate 56 and running perpendicular to the direction of movement B of the plate 56. The design of the shaft 100 is explained in more detail in connection with FIG. 4. The shaft 100 comprises a circular cylindrical shaft part 110, which is arranged between a first and a second shaft hub 112 and 114, respectively. When assembled, the first shaft hub 112 rotates slidingly in the end wall and the second shaft hub 114 rotates slidingly in the rear wall.

[0133] The outer periphery of the shaft part 110, in planes perpendicular to the axis of rotation H, forms control cams 122, which are intended to interact with the drive area 102 of a plate 56 at the contact point 103. The control cams 122 are symmetrical in pairs with respect to a mirror plane running through a centrally arranged control cam, said control cams being perpendicular to the axis of rotation H of the shaft 100.

[0134] The section of the control cam 122 in which the control cam is in contact with the drive area 102 of the relevant plate 56 when the shaft 100 is turned is called the effective portion 124 of the control cam 122.

[0135] The effective portions 124 of the control cams 122 have a V-shaped arrangement as seen in the unwinding of the shaft, with the central effective portion forming the tip of the V-shape and the other effective portions 124 being offset forward with respect to the tip of the V-shape as seen in the direction of rotation S from the operating position to the initial position. The direction of rotation W indicates the direction of rotation from the initial rotary position to the operating rotary position.

[0136] In the effective portion 124 of the control cam, which extends from point A to point C in FIG. 4, the radius R increases continuously from a first radius R1 corresponding to point A to a second radius R2 corresponding to a larger radius R2 corresponding to point C. The radius R1 and R2 are assigned to the operating position 60 and the initial position 58 of the respective plate 56, respectively. The effective section 124 forms an essentially spiral arc of the control cam 122.

[0137] One end face 128 of the shaft 100 has a circular arc-shaped groove 130 centric to the axis of rotation H to accommodate a pin 131 fixed relative to the chamber. One end 132 of the groove 130 forms a first rotary stop 134 of the shaft 100 assigned to the operating rotary position and the other end 136 forms a second rotary stop 138 of the shaft 100 assigned to the initial rotary position. To transfer the plates 56 from the operating position 60 to the initial position 58, the shaft 100 is turned in one direction of rotation S from an operating rotary position, in which the plates 56 are in the operating position 60, to an initial rotary position, in which the plates 56 are in the initial position 58. In FIG. 3, the shaft 100 is shown in the operating rotary position.

[0138] The control cams 122 are designed in such a way that the radius of the respective control cams increases when turning the shaft 100 from the operating rotary position to the initial rotary position. The radius increases continuously between the operating position and the initial position to allow continuous movement of the plates 56 when turning the shaft 100.

[0139] When turning the shaft 100 from the operating rotary position to the initial rotary position, the control cam 122 comes into contact with the drive area 102 of the plate 56 in question.

[0140] As the shaft 100 continues to rotate, the control cam therefore pushes the plate 56 assigned to it further and further in the direction of initial position 58, with the magnet 20 simultaneously exerting an attractive force F′ in the direction of operating position 60. As a result, the plates 56 are lowered from the operating position 60 and the plates 56 remain in contact with the corresponding control cam 122.

[0141] To move the plates 56 from the initial position 58 to the operating position 60, the shaft 100 is rotated in the opposite direction to the direction of rotation S. The shaft 100 is driven by a motor back and forth between the initial rotary position and the operating rotary position.