EXTRUSION PRESS

Abstract

An extrusion press for extrusion of a material to be pressed through a die has a recipient that holds the material to be pressed, and a module that can be displaced relative to the die. The module can be acted on, during extrusion, by an electric motor drive, with the force required for extrusion. The electric motor drive is connected to the module that is displaceable relative to the die, by a bearing unit that has play perpendicular to the force; and/or during extrusion, drives contraction devices for contraction of a region of a tension element that stands under tension, which element counters the force required for extrusion by tension, and/or is a linear drive, which displaces a module that is fixed in place relative to the die during extrusion and the module that is displaceable relative to the die during extrusion, relative to one another, during extrusion.

Claims

1. An extrusion press (10) for extrusion of a material to be pressed (11) through a die (12), having a recipient (13) that holds the material to be pressed (11), and having a module (31) that can be displaced relative to the die (12), which module can be acted on, during extrusion, by an electric motor drive (40), with a force that is required for extrusion, wherein the electric motor drive (40) (i) is connected to the module (31) that is displaceable relative to the die (12), by means of a bearing unit (60) that has play perpendicular to the force; and/or (ii) during extrusion, drives contraction means (70) for contraction of a region of a tension element (71) that stands under tension, which element counters the force required for extrusion by means of tension, and/or (iii) is a linear drive (73), which displaces a module (32) that is fixed in place relative to the die (12) during extrusion and the module (31) that is displaceable relative to the die (12) during extrusion, relative to one another, during extrusion.

2. The extrusion press (10) according to claim 1, wherein the bearing unit (60) is a cardanic joint (61) and/or comprises a socket (62) that has two degrees of freedom.

3. The extrusion press (10) according to claim 1, wherein the contraction means (70) comprise the linear drive (73), and the module (32) that is fixed in place relative to the die (12) is connected to the module (31) that is displaceable relative to the die (12) by way of the tension element (71) during extrusion, by way of tension.

4. The extrusion press (10) according to claim 1, wherein the electric motor drive (40), in particular the linear drive (73), is a direct drive and/or comprises a linear actuator, wherein the tension element (71) preferably has a stator (74) of the linear actuator.

5. The extrusion press (10) according to claim 1, further comprising a spindle (21) and a nut (22) that can be axially displaced with regard to the spindle (21), wherein preferably the spindle (21) or the nut (22) is driven to rotate by means of the electric motor drive (40) and/or wherein preferably the spindle (21) is comprised by the tension element (71) or represents parts of it.

6. The extrusion press (10) according to claim 1, wherein the linear drive (73) comprises a seal (76) that preferably seals off moving modules toward the outside, for example in the form of folding bellows (77).

7. The extrusion press (10) according to claim 1, wherein the tension element (71) comprises at least one, preferably two, three or four tension rods (72).

8. The extrusion press (10) according to claim 1, wherein the tension-element (71), preferably the tension rod or rods (72), engages on a die crossbeam (15) as a or the module (32) that is fixed in place relative to the die (12) and/or on a counter-crossbeam or moving crossbeam (17) as a or the module (31) that is displaceable relative to the die (12), during extrusion, with tension.

9. The extrusion press (10) according to claim 1, wherein the module (31) to which force is applied is guided by way of at least one moving crossbeam (17) or is the moving crossbeam (17).

10. The extrusion press (10) according to claim 1, wherein the module (31) to which the force is applied and which is displaceable relative to the die (12) is the extrusion punch (14) or carries the extrusion punch (14) and is preferably configured in one piece with it.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Other objects and features of the invention will become apparent from the following detailed description considered in connection with the accompanying drawings. It is to be understood, however, that the drawings are designed as an illustration only and not as a definition of the limits of the invention.

[0078] In the drawings,

[0079] FIG. 1 shows a first extrusion press having a rotating spindle and a fixed nut, in a schematic view;

[0080] FIG. 2 shows a second extrusion press having a rotating spindle and a fixed nut, but one that migrates along, in a schematic view;

[0081] FIG. 3 shows a third extrusion press having two arrangement parts, as well as having a rotating nut and a fixed spindle, in a schematic view;

[0082] FIG. 4 shows a top view, in the pressing direction, of the extrusion press according to FIG. 3;

[0083] FIG. 5 shows a representation, as an example, of a ball screw, in a perspective view;

[0084] FIG. 6 shows a representation, as an example, of a roller gear drive, in a perspective view;

[0085] FIG. 7 shows a side view of the roller gear drive according to FIG. 6;

[0086] FIG. 8 shows a representation, as an example, of a planetary roller gear drive, in a perspective view;

[0087] FIG. 9 shows a top view of the planetary roller gear drive according to FIG. 8;

[0088] FIG. 10 shows a fourth extrusion press having a cardanic joint as the bearing unit;

[0089] FIG. 11 shows a fifth extrusion press having a socket as the bearing unit; and

[0090] FIG. 12 shows a sixth extrusion press having contraction means that comprise a linear drive, in each instance.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0091] The extrusion presses 10 shown in FIGS. 1 to 4 and 10 to 12 are suitable and intended, in each instance, for pressing material 11 to be pressed through a die 12. In this way, wires, rods or other prismatic profiles having relatively complex cross-sections can be extruded from the material 11 to be pressed, which can comprise, for example, blocks that have ceramic or hard material, if applicable also composed of powders or granulates.

[0092] For extrusion, the material 11 to be pressed, in each instance, has a pressing force applied to it and is pressed through the die 12 in the extrusion direction 50.

[0093] In order for the material 11 to be pressed to be forced through the die 12, a recipient 13 is provided, into which an extrusion punch 14 can plunge, so as to apply the pressing forces.

[0094] The extrusion presses 10 shown in the drawing represent direct presses in each instance, in this regard, in which the extrusion punch 14 acts directly on the material 11 to be pressed and follows the pressing direction 50 for extrusion. Alternatively, the extrusion presses 10 can also be configured as indirect presses, in which the extrusion punch 14 carries the die 12, in each instance, and a press-down plate is displaced jointly with the recipient 13, against the die 12 and the extrusion punch 14, which accordingly leads to the result that the die 12 and the extrusion punch 14 plunge into the recipient 13, counter to the pressing direction, for extrusion.

[0095] In the present exemplary embodiments, the corresponding extrusion punch 14 is carried by a moving crossbeam 17, and these can jointly be displaced, as a module 31, with reference to the die 12. It is understood that further components, such as, for example, a connection piece 36 and a nut crossbeam 35 that migrates along (see FIG. 2) can also be included in this displaceable module 31, if applicable. In the case of an indirect press, the press-down plate as well as the moving crossbeam 17 would be combined into the module 31 that is displaceable relative to the die 12, wherein here, too, further components such as, for example, the nut crossbeam 35 and the connection piece 36, can be included, if applicable.

[0096] The die 12 is carried by a die crossbeam 15, wherein these two form a module 32 that is fixed in place relative to the die 12, and further components can still be included in this moduledepending on the desired definitionwhich remain fixed in place relative to the die 12 during extrusion. In the case of an indirect press, the related extrusion punch 14 would also be included in the module 32 that is fixed in place relative to the die 12.

[0097] For the actual extrusion process, the two modules 31, 32 are displaced relative to one another, so that these two modules 31, 32 represent the essential effective modules 30 that must be displaced relative to one another for extrusion.

[0098] In the case of the present exemplary embodiments, the pressing forces are applied by means of an electric motor drive 40, which ultimately supports itself on the die crossbeam 15 by way of a tension element 71 or tension rod 16, with tension, so that in this manner, the pressing forces can be countered. In the case of the extrusion presses 10 shown in FIGS. 1, 2, 10, and 11, the electric motor drive 40 or a spindle/nut arrangement 20 driven by it supports itself, in each instance, on a counter-crossbeam 18, on which the tension element 71 or the tension rods 16 engage accordingly, with tension. In the case of the exemplary embodiments shown in FIGS. 3 and 12, in contrast, the counter-crossbeam 18 merely has a stabilizing function. The electric motor drive 40 or a nut 22 is provided on the moving crossbeam 17 in the case of the extrusion press 10 according to FIG. 3, so that tension forces can be transferred to the tension rods 16 by way of this nut 22. In the case of the exemplary embodiment according to FIG. 12, instead of a nut 22 that interacts with a spindle 21 carried by the tension rods 16, a rotor 75 of a linear drive 73 is arranged on the moving crossbeam 17 or configured as the latter, which rotor then can support itself on the tension rod 16, which is configured as the stator 74 of the linear drive 73, so that in the case of this exemplary embodiment, as well, the counter-crossbeam 18 merely serves for stabilization purposes.

[0099] In order to apply the pressing forces, the exemplary embodiments shown in FIGS. 1 to 3, 10 and 11 each have spindle/nut arrangements 20, which comprise a spindle 21 and a nut 22.

[0100] In this regard, in the case of the exemplary embodiment according to FIG. 3, the nut 22 is driven by the electric motor drive 40, while in the case of the exemplary embodiments according to FIGS. 1, 2, 10 and 11, the spindle 21, in each instance, is driven by the electric motor drive 40. It is understood that the corresponding types of drives can also be reversed, in that in the case of the exemplary embodiment according to FIGS. 1, 10 and 11, the nut 22 is driven to rotate, while in the case of the exemplary embodiment according to FIG. 3, a rotational drive of the spindle 21 can take place, while the nut 22 is fixed in place. Ultimately, the important thing is a relative movement between these two modules, by means of which movement the rotational movement of the electric motor drive 40 can be converted into a linear movement in the pressing direction 50 or opposite to it.

[0101] The spindle/nut arrangements 20 are configured, in the present case, as rolling screw threads 23, in order to be able to apply the greatest forces possible with little friction. Depending on the concrete embodiment, here ball screws 80 or roller screws 90 can advantageously be used, as they are explained below, using FIGS. 5 to 9. On the other hand, it is understood that in deviating embodiments, the spindle/nut arrangements 20 can also conventionally provide for a friction interaction between spindle 21 and nut 22, wherein in this regard, supplemental lubrication, for example hydrostatic lubrication, can be provided, if necessary.

[0102] A ball screw 80, as it can be used as explained above and is shown as an example in FIG. 5, comprises the spindle 21 and a nut 22 configured as a ball screw nut 82, which also comprises a ball return 83 and forms raceways 84 together with the spindle 21. Furthermore, the ball screw 80 comprises balls 81 that run in the raceways 84 and the ball return 83 during a relative rotational movement between nut 22 and spindle 21.

[0103] An electric motor drive 40 drives the spindle 21 with reference to the nut 22 or vice versa. Between the spindle 21 and the ball screw nut 82, the balls 81 move in the raceways 84, which migrate axially during rotation of the spindle 21. The movement of the balls 81 takes place as rolling off or rolling away. The ball return 83 in the ball screw nut 82 transports the balls 81 back and thereby closes the circuit in which the balls 81 circulate.

[0104] While in the case of conventional worm gears having surfaces that slide on one another, 50 to 90% of the power introduced is converted to heat, the present ball screw 80 with its ball screw drive has less friction due to the rolling movement of the balls 81. In this way, a lower drive power can be sufficient, and this is particularly advantageous when using an electric motor drive 40. Furthermore, the total wear and, in particular, the wear between spindle 21 and ball screw nut 82 is less.

[0105] It is understood that for the spindle/nut arrangement 20 of the other exemplary embodiments, and also of alternative embodiments, such ball screws 80 or also ball screws having a different structure can be used.

[0106] In an alternative embodiment, a roller screw 90 can also be used as a rolling screw thread 23 for the spindle/nut arrangement 20 or in the case of the present exemplary embodiments.

[0107] Such a roller screw 90 could also be configured, for example, as a roller screw drive 97, as it is shown in FIGS. 6 and 7.

[0108] In this regard, the roller screw drive 97 comprises a spindle 21 and a nut 22 configured as a recirculating roller nut 92. Rollers 91, which have circular grooves 99, in each instance, run around the spindle 21. Because the rollers 91 with their grooves 99 run around the spindle 21, a relative movement in the axial direction takes place. A correspondingly configured recirculating roller nut 92 also comprises a roller return 98. The roller return 98 serves for lifting the rollers 91 up from the spindle and setting them back in place.

[0109] Due to the radial and axial movement of the rollers 91, the recirculating roller nut 92 is configured in the manner of a cage, so as to hold the rollers 91 in position.

[0110] For the extrusion presses 10 of the present exemplary embodiments, the roller screw 90 can also be configured as a planetary roller screw drive 93, as it is shown, for example, in FIGS. 8 and 9.

[0111] The planetary roller screw drive 93 comprises rollers 91 having a thread 94, which rollers rotate about a spindle 21 with its thread 94, in recirculating roller nuts 92 that are configured to be ring-shaped. By means of this rotation, an axial relative movement between 22 and spindle 21 occurs.

[0112] The diameter of the spindle 21, the rollers 91, and the recirculating roller nut 92 are selected in such a manner that the circumferential speeds of spindle 21 and rollers 91 match. The synchronization is taken on by a ring 95 integrated into the recirculating roller nut 92, which ring has an inner gearing that engages into sprockets 96 at the ends of the rollers 91.

[0113] In the case of the present planetary roller screw drive 93, the rollers 91 or roller bodiesin contrast to the exemplary embodiments according to FIG. 5 as well as 6 and 7do not move relative to the recirculating roller nut 92 in the longitudinal direction, so that no return mechanism is necessary. This can make higher speeds of rotation possible.

[0114] Roller screws 90 also allow a corresponding reduction in friction, and this incidentally also holds true for screws having hydrostatic nuts 65. Also, the combination of rolling screw threads 23 with a hydrostatic bearing or in such a manner that the nuts of the rolling screw threads 23 are then configured to be hydrostatic, can be used accordingly for a reduction in friction, wherein it is understood that these advantages are already correspondingly advantageous individually, in particular as compared with solutions known from the state of the art.

[0115] In the case of the exemplary embodiments shown in FIGS. 1, 2, 10, and 11, the electric motor drive 40 is implemented, in each instance, by means of a direct drive, which comprises a stator 41 and a rotor 42 that rotates with the corresponding spindle 21. It is understood that in deviating embodiments, other drives or types of drives can also be used, in particular, for example, transmission drives, which can actually be switched, if applicable.

[0116] Because in the case of the exemplary embodiment according to FIGS. 1, 10, and 11, the spindle 21, in each instance, is displaced together with the moving crossbeam 17, in the case of these exemplary embodiments the stator 41 is correspondingly configured to be longer than in the case of the exemplary embodiment according to FIG. 2, according to which the spindle remains fixed in place with reference to the die 12, while a corresponding hydrostatic nut 65 moves together with the moving crossbeam 17, so that the stator 41 can be configured to be correspondingly shorter.

[0117] In this regard, the hydrostatic nut 65, in the case of the exemplary embodiment according to FIG. 2, is mounted on a nut crossbeam 35, to float perpendicular to the pressing direction 50, so that in this manner, a bearing unit 60 is made available, which has play perpendicular to the pressing direction 50 and thereby perpendicular to the force required for extrusion.

[0118] It is understood that if applicable, mounting directly on the moving crossbeam 17 or direct placement of nut crossbeam 35 and moving crossbeam 17 one behind the other is possible, while in the case of this exemplary embodiment, a connection piece 36 having the function of a spacer is additionally provided between the nut crossbeam 35 and the moving crossbeam 17.

[0119] For lubrication purposes, the hydrostatic nut 65 of the exemplary embodiment according to FIG. 2 carries a bearing agent pump 66 and a bearing agent container 67, so that the hydrostatic nut 65 can be sufficiently lubricated both in its contact with the spindle 21 and in the bearing unit 60 relative to the nut crossbeam 35.

[0120] In particular, a hydrostatic nut 65 can advantageously be used both in the case of spindle/nut arrangements 20 having a rotating nut 22 and those having a non-rotating nut 22, wherein it appears to be significantly easier, in the case of a non-rotating nut 22, to make the hydraulic bearing agent available at the required locations, because it is possible to do without rotary unions or the like.

[0121] Also, the exemplary embodiment according to FIG. 2 carries a further bearing agent pump 66 having a bearing agent container 67, in the region of the electric motor drive 40, by means of which, in particular, a hydrostatic bearing 69, which can absorb forces of the spindle 21 onto the counter-crossbeam 18, which forces are directed counter to the pressing forces, can be lubricated.

[0122] It is true that the bearing agent pump 66 and the bearing agent container 67 mean additional effort for the hydrostatic bearings or lubrications, in particular an additional hydraulic effort, which effort is actually supposed to be avoided by means of the use of electric motor drives 40. On the other hand, this additional effort is not comparable to the effort and the risks when using hydrostatic drives instead of the electric motor drive 40, and is significantly less than the effort and the risks when using hydrostatic drives.

[0123] Furthermore, the exemplary embodiment shown in FIG. 2 also has a drive journal 49, which is configured on the side of the spindle 21 that faces the electric motor drive 40, and which carries the rotor 42, so that the latter is replaceable. Such an embodiment makes it possible to quickly replace the electric motor drive 40, if necessary, or to adapt it to specific requirements.

[0124] On the other hand, the spindle 21 in the case of the exemplary embodiment according to FIG. 2 is also mounted axially in the counter-crossbeam 18, by means of a return bearing 26 as well as two axial bearings 27.

[0125] It is understood that the reversal of effect, which is represented in FIG. 2, as compared with the exemplary embodiments according to FIGS. 1, 10 and 11, can also be implemented, if applicable, in the case of the latter exemplary embodiments. The same holds true for the use of the drive journal 49, so as to increase the flexibility with regard to the electric motor drive 40 that is ultimately used.

[0126] Also, the floating bearing of the hydrostatic nut 65 of the exemplary embodiment according to FIG. 2 can be used in the case of the embodiment according to FIGS. 1, 10, and 11, wherein these, however, implement alternatives in this regard, which in turn can also be used in the case of the exemplary embodiment according to FIG. 2.

[0127] Thus, the extrusion press 10 according to FIG. 1 uses mounting of the spindle 21 on the moving crossbeam 17 by means of an axially acting roller bearing 25 as well as by means of an axially acting return bearing 26, so that in this way, as well, a bearing unit 60 is made available, which allows play perpendicular to the pressing direction 50 or perpendicular to the force applied for extrusion.

[0128] The exemplary embodiment according to FIG. 10 uses a cardanic joint 61 at this location, wherein sliding mounting of this cardanic joint in response to pull and push is not shown separately in the case of this exemplary embodiment, but this cardanic joint 61 also brings about play perpendicular to the pressing direction 50 or to the force applied for extrusion. Instead of sliding mounting, roller bearings can also be used here, if applicable.

[0129] Specifically for making available play perpendicular to the pressing direction 50 or to the force required for extrusion, the arrangement according to FIG. 11 uses a socket 62 that is formed in a suitable manner, so as to allow corresponding play perpendicular to the force applied for extrusion or to the pressing direction 50 in this manner. In the case of this exemplary embodiment, the return stroke is also implemented by means of a slide bearing (not numbered), wherein instead of the slide bearings, roller bearings can also be used. Also, it is understood that these solution approaches can also be implemented, in a suitable manner, in the case of the other exemplary embodiments.

[0130] In the case of the exemplary embodiments according to FIGS. 3 and 12, contraction means 70 are provided, in each instance, which contract the tension elements 71.

[0131] In this regard, in the case of these exemplary embodiments according to FIGS. 3 and 12, it is provided, in each instance, that the individual tension rods 60 are contracted, in terms of their effectiveness, in that the point at which the forces directed counter to the pressing forces are absorbed is displaced closer to the module 32 that is fixed in place relative to the die 12.

[0132] This can be done, in particular, in that the point of attack at the tension rods 16 is displaced accordingly, and this can be implemented in that the contraction means 70 correspondingly displace a nut 22 (see FIG. 3) or a rotor 75 (see FIG. 12) along the tension rods, which then can be configured as a spindle 21 (see FIG. 3) or as a stator 74 (see FIG. 12).

[0133] It is understood that in deviating embodiments, the method of effect of spindle 21 or stator 74, on the one hand, as well as nut 22 and rotor 75, on the other hand, can be interchanged, in that, for example, the spindle 21 rotates and the nut 22 is held in place. Also, for example, the tension rod 16 can be configured as the rotor of the linear drive 73 and, vice versa, a stator of the linear drive 73 can be provided on the moving crossbeam 17.

[0134] In the case of the exemplary embodiments according to FIGS. 3 and 12, the contraction means 70 or the individual drive elements of the electric motor drive 40 are provided in partial arrangements 24 corresponding to the placement of the tension rods 16. It is understood that in particular, the linear drive 73 can also be used in the case of the arrangements according to FIGS. 1, 2, 10, and 11, if applicable, wherein stator 74 and rotor 75 can be used, depending on the concrete requirements, instead of the spindle 21 or the nut 22.

[0135] In particular, the linear drive 73, as shown in FIG. 12, can be configured as a linear actuator. Specifically in the case of such an embodiment, there is the risk that due to the magnetic effects, but possibly also due to electric or electrostatic effects, contamination can occur to a greater degree. For this reason, in the case of the exemplary embodiment according to FIG. 12, a seal 76 in the form of folding bellows 77 is provided.

[0136] It is understood that in deviating embodiments, instead of a folding bellows 77, other seals can also be provided, as long as these are suitable for sealing off the critical regions.

[0137] It is also understood that in the case of the other embodiments, corresponding seals can be provided at suitable locations, if this appears to be advantageous, for example in the case of the electric motor drives 40 of the exemplary embodiments according to FIGS. 1, 2, 10, and 11, which are configured as direct drives, or in the case of the friction surfaces of the spindles 21 or nuts 22.

[0138] Although only a few embodiments of the present invention have been shown and described, it is to be understood that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention.

TABLE-US-00001 Reference Symbol List: 10 extrusion press 11 material to be pressed 12 die 13 recipient 14 extrusion punch 15 die crossbeam 16 tension rod 17 moving crossbeam 18 counter-crossbeam 20 spindle/nut arrangement 21 spindle 22 nut 23 rolling screw thread 24 partial arrangement 25 roller bearing of the spindle 21 26 return bearing 27 axial bearing of the spindle 21 30 module 31 module that can be displaced relative to the die 12 32 module fixed in place relative to the die 12 35 nut crossbeam 36 connection piece 40 electric motor drive 41 stator 42 rotor 49 drive journal 50 pressing direction 60 bearing unit 61 cardanic joint 62 socket 65 hydrostatic nut 66 bearing agent pump 67 bearing agent container 69 hydrostatic bearing 70 contraction means 71 tension element 73 linear drive 74 stator of the linear drive 73 75 rotor of the linear drive 73 76 seal 77 folding bellows 80 ball screw 81 ball 82 ball screw nut 83 ball return 84 raceways 90 roller screw 91 roller 92 recirculating roller nut 93 planetary roller screw drive 94 thread 95 ring 96 sprocket 97 roller screw drive 98 roller return 99 grooves