Extrusion press

Abstract

To achieve a good extrusion result in spite of the use of an electric motor drive for making available the force required for extrusion.SOLUTION: The invention proceeds from a basic inventive idea of undertaking design means that allows the most uniform and precise possible force effect of pressing forces on a material to be pressed.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an extrusion press for pressing a material through a die, having a receptacle for holding the material to be pressed and having an extrusion punch that can be moved relative to the die (12), at least one module of the extrusion press being able to be influenced with the force required for the extrusion process by means of an electric motor drive while the extrusion process is taking place. [Background technology]

[0002] From DE 10 2015 116 002 C1 an extrusion press is known for pressing a material through a die, which has a receptacle for holding the material to be pressed and an extrusion punch which can be moved relative to the die, where the pressing force is applied by a hydraulic drive. Such an apparatus has proven to be sufficient in itself to apply particularly very large pressing forces.

[0003] From patent 6143142 and EP 3470146, an extrusion press for pressing a material to be pressed is also known, which has a receptacle for holding the material to be pressed and an extrusion punch that can be moved relative to a die, where the pressing force is applied using an electric motor. Such an apparatus seems particularly suitable for extrusion presses in which lower pressing forces are supposed to be applied, and is equipped with a nut / spindle, where an electric motor drives to rotate a nut, which in turn acts on a spindle attached to an extrusion punch, or some other module capable of applying the force required for the extrusion process. Thereby, the rotary movement of the electric motor is converted into a linear movement, the pressing force is applied and the extrusion punch or the corresponding module is moved back and forth. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] German Patent Invention No. 102015116002 [Patent Document 2] Patent No. 6143142 specification [Patent Document 3] European Patent No. 3470146 Summary of the Invention [Problem to be solved by the invention]

[0005] It is an object of the present invention to achieve good extrusion results even when using electric motor drives in order to make the necessary forces for extrusion available. [Means for solving the problem]

[0006] The object of the invention is achieved by an extrusion press having the features of the independent claims. Further advantageous embodiments, if applicable apart from these, can be found in the dependent claims as well as in the following description.

[0007] In order to make the necessary forces for extrusion available, and to achieve good extrusion results even when using electric motor drives, the present invention proceeds from the basic inventive idea in implementing design measures, which allow the most uniform and precise possible force effect of the pressing force on the material being pressed.

[0008] The most uniform and precise possible force effect of the pressing force on the material to be pressed, and therefore a good extrusion result, can be achieved by using an extrusion press, which has a receptacle for holding the material to be pressed through a die, and a module that can be moved relative to the die. If the extrusion press is characterized in that an electric motor drive is connected to a module that can be moved relative to the die by a bearing unit with play perpendicular to the force, to this module the force required for the extrusion can be applied by the electric motor drive during the extrusion process.

[0009] The bearing unit with play perpendicular to the force creates, on the one hand, the possibility of equalization for possible lateral forces occurring perpendicular to the force required for the extrusion process, so that in particular the electric motor drive can work as optimally as possible with respect to its drive power. In particular, possible lateral forces occurring perpendicular to the force required for the extrusion process and which may impede the movement of the movable module can also be absorbed appropriately. On the other hand, the force applied by the electric motor drive to the movable module or to the locally fixed module on which the electric motor drive supports itself is impeded as little as possible by the bearing unit with play perpendicular to the force, so that the force required for the extrusion process can be applied in such a way that it reduces as little as possible.

[0010] In the case of a suitable design, such guidance of the movable modules can also relieve stresses, thereby reducing possible irregularities during the extrusion process, such as unintentional jumping or vibrations, to a minimum, thereby thus achieving good extrusion results.

[0011] In this regard, any play in the bearing units, which allows the force required for the extrusion process to be expressed as a vector and thereby allows for movements perpendicular to this force, can improve, depending on the circumstances, the uniform and precise force effect of the pressing force on the material to be pressed, thereby improving the result of the extrusion process.

[0012] In this connection it does not initially play any role whether the corresponding play involves only translational aspects or also rotational aspects, in particular with a rotation axis perpendicular to the force vector. In particular, it appears to be advantageous if both translational and rotational aspects are at least to some extent counterbalanced by play.

[0013] Finally, any bearing unit capable of transmitting forces, in particular the forces required here for the extrusion process, and having a play perpendicular to the force can be used as the bearing unit with play perpendicular to the force, in particular the bearing unit can be equipped with a floating bearing for this purpose, which allows a corresponding play perpendicular to the force that can be applied to the floating bearing.

[0014] The bearing unit can in particular comprise a cardanic joint, which, due to its properties, allows the force, in other words the pressing force here, to be transmitted along the respective axis of rotation and to be tilted with a perpendicular component to this force. On the other hand, the bearing unit can comprise a socket, which has at least one degree of freedom, preferably at least two degrees of freedom, which, depending on the circumstances, preferably has at least one perpendicular component to the forces required for the extrusion process. In this way, the bearing unit can be made available in a structurally simple manner. The unit has a play perpendicular to the forces required for the extrusion process.

[0015] The corresponding play allows, on the one hand, in particular the electric motor drive to be correspondingly relieved of stress, in particular the corresponding play allows the connections of possible gear mechanisms, such as for example the spindle drive, to be correspondingly relieved of stress from forces which occur perpendicularly to the forces required for the extrusion process.

[0016] Apart from the combination of the above mentioned features, an extrusion press for extruding a material to be pressed through a die, comprising a receptacle for holding the material to be pressed and a module which can be moved relative to the die and which during the extrusion process can be influenced by an electric motor drive with the force required for the extrusion process, can be characterized in that the electric motor drive drives a contraction means for contracting the area of ​​the tensioning element subjected to tension during the extrusion process, which tensioning element opposes the force required for the extrusion process by tensioning in order to achieve a good extrusion result. This also represents a design measure, when suitably configured, which allows the most uniform and precise possible force effect of the pressing force on the pressed material.

[0017] Thus, extrusion presses generally apply the necessary pressing force between the die and a punch disposed on a movable cross beam to press the material being pressed through the die. Generally, the pressing force in this context is applied by moving the movable cross beam towards the die in the extrusion direction or vice versa.

[0018] In order to completely prevent the material to be pressed from escaping radially out of the die or from any arbitrary escaping, a receptacle is generally provided, which is able to resist the radial expansion of the material to be pressed during the extrusion process. Preferably, the receptacle is sealed in a suitable manner against the die or against the movable cross beam or punch, so that the material to be pressed can resist the pressing force applied by the relative movement of the movable cross beam to the die, since the material to be pressed can only exit through the die.

[0019] In this context, the term "receptacle" is therefore understood to mean any module capable of holding the material to be pressed and limiting the radial expansion of the material to a desired extent during the extrusion process. Preferably, the receptacle is sealed against the die and / or punch or the movable cross beam, so that the material to be pressed cannot or hardly can escape from the space bounded by the movable cross beam or punch, the receptacle and the die in any other way than through the die.

[0020] Finally, there are also extrusion presses which act indirectly, in which the die itself is generally arranged on a punch, which is optionally constructed hollow so as not to prevent the material from passing through the die. In such an embodiment, a corresponding sealing plate on the opposite side of the punch and die, in other words on the movable cross beam, is sufficient. This plate simply needs to ensure an adequate seal against the receptacle.

[0021] Similarly in this exemplary embodiment, the punch is configured to penetrate into the receiver based on the movement of the movable cross beam, in this way reducing the space remaining for the material to be pressed within the receiver during the extrusion process.

[0022] It should be understood that mixed configurations of direct and indirect presses are also conceivable and ultimately are non-existent or rarely present on the market.

[0023] To counter the applied pressing force, extrusion presses generally comprise a press frame, which comprises on the one hand a cross beam for the die and on the other hand a counter beam, which are connected to each other by tie rods, so that a corresponding drive, for example an electric motor drive, can support itself on the counter beam and apply a pressing force to the movable cross beam. In such an embodiment, the corresponding force between the counter beam and the movable cross beam is applied by a spindle, by several spindles or by one or several shoe pistons, which finally results in the desired movement of the movable cross beam.

[0024] Finally, however, the force is not applied to the movable cross beam, but rather in the direction of movement of the die, which is supposed to play a role in the extrusion process. It is also conceivable to pull the movable cross beam directly against the die cross beam, which can in particular be done by means of a tension rod. In the case of such an embodiment, it is in particular possible to use the contraction means to contract the tension rod accordingly, and to apply a pressing force or a movement of the movable cross beam by means of this contraction process.

[0025] In the case of such an embodiment, it may be possible to do without a counter beam at all. Depending on the concrete implementation, it may be advantageous to use a counter beam, for example for stability purposes or as a bearing body for the tension rod in the part of the tension rod where tension is no longer applied. For example, the counter beam can be provided in a conventional manner at the end of the tension rod, which is placed in each case opposite the die beam. However, if contraction means are provided, for example, on the die beam, so that the tension rod is driven off the die beam parallel to the material to be pressed and leaves the die in exactly this direction of movement, it may be advantageous to provide a corresponding stabilization of these protruding ends on the side of the counter beam or the die beam facing away from the receiver in order to stabilize the tension rods protruding outwards.

[0026] While the contraction means can thus contract the tensioned area of ​​the tensioning element of the extrusion press, it is not essential that the tensioning element itself is contracted by the contraction means depending on the circumstances. Such a contraction can generally be very complicated in terms of construction, since in particular a corresponding contraction of the tensioning element has to take place in the tensioned situation, and a new stretching of the tensioning element may be necessary for a new extrusion process after the current extrusion process. It would therefore generally be easier if the contraction means only contracts the tensioned area of ​​the tensioning element and this is implemented in a constructionally simple manner, for example by means of a cable winch, a spindle or a linear drive.

[0027] In this context, the related term "contraction means" refers to any device capable of contracting the area subjected to tension of the tensioning element. This then results in contracting the distance between the modules connected to each other by the tensioning element during the extrusion process and in applying tension to the tensioning element. This could possibly be a module fixed in place relative to the die or a module that is movable depending on the situation, in particular a module that is movable relative to the die, which has already been mentioned above.

[0028] In particular, apart from the combination of the above mentioned features, an extrusion press for the extrusion of a material to be pressed through a die, comprising a receptacle for holding the material to be pressed and a module which can be moved relative to the die and which can apply the necessary force for the extrusion during the extrusion process by means of an electric motor drive, can be characterized in that the electric drive is a linear drive which moves modules which are fixed in position relative to the die during the extrusion process and modules which are movable relative to each other during the extrusion process and relative to the die during the extrusion process, thereby achieving good extrusion results. In this connection, it has been found that the use of linear drives is a design measure which allows a more uniform and precise possible force effect on the material to be pressed, depending on the circumstances.

[0029] As already explained above, it appears relevant to move one module relative to the die during the extrusion process, thereby exerting a pressing force on the material thus pressed and forcing it through the die.

[0030] In this context, the term module that can be moved relative to the die is therefore to be understood as meaning any module of the extrusion press that can be moved relative to the die. Preferably, this module is acted upon by at least a part of the pressing force, preferably by the entire pressing force. In particular, the corresponding movable module can be made available by a movable cross beam. Likewise, the punch itself or the sealing plate can represent a corresponding movable module.

[0031] Preferably, the movable module is driven by a drive, in particular an electric motor drive. In this connection, it is to be understood that the electric motor drive module does not necessarily or need not be included in the movable module. In particular, for example a spindle, although also moved, can be considered as part of the drive or as part of the gear mechanism between the drive and the movable module, and not as part of the movable module.

[0032] Finally, all modules of the extrusion press which remain or can remain fixed in position relative to the die during the extrusion process can be considered as locally fixed modules in this context. In particular, for example, the die cross beam can generally be defined as a locally fixed module, which is correspondingly locally fixed relative to the die. The same applies to the punch in an indirect press. In general, the tension rod and the counter beam can also be considered as locally fixed modules relative to the die during extrusion, if the drive acts on the movable cross beam, supporting itself on the counter beam and moving it on the movable cross beam. On the other hand, it is also considered that the counter beam is not a locally fixed module relative to the die, for example, if the counter beam itself is moved during the extrusion process, i.e. if the counter beam serves as a positioning element for the ends of the tie rods, likewise the ends of the tie rods are moved relative to the die, and they use, for example, the aforementioned contraction means. In the case of a direct press, the receiver also remains locally fixed relative to the die during the extrusion process, whereas the receiver in an indirect press is generally moved together with the movable cross beam and therefore cannot be considered as a locally fixed module.

[0033] In this context, the term "linear drive" refers to any electric motor drive capable of converting electrical energy into linear motion.

[0034] In particular, the linear drive can be a direct drive or can comprise a linear actuator, whereby the conversion of electrical energy into linear motion can be performed structurally precisely and in particular with reduced possibility of using further gearing elements or without further gearing elements.

[0035] Thus, the electric motor drive can also be a direct drive.

[0036] Direct drives are characterized by very few gearing elements, and in particular the absence of any separate gearing elements, thereby providing the most direct possible conversion of electrical power to linear motion or force. In particular, direct drives generally also provide linear motion and utilize a gearing element or elements, such as a nut, screw, or spindle, which is preferably not necessary in the case of linear drives.

[0037] In particular, for example torque motors or motor spindles are possible direct drives. In particular, linear actuators or linear motors can be correspondingly configured as direct drives, if applicable. Furthermore, brushless DC motors can be advantageously used as electric motor drives or direct drives, as required.

[0038] In particular, the contraction means can comprise a linear drive. The contraction means thus move the modules fixed locally relative to the die during the extrusion process, preferably by their linear drive, with the contraction of all modules, in each case the tensioned area of ​​the tensioning element or the tensioning rod of this element, against the modules movable relative to the die during the extrusion process. Such an embodiment has a particularly compact construction and makes it possible, in particular by the linear drive, to distribute the forces applied to all modules or tensioning rods of the tensioning elements, as long as all of these are able to compensate for any tilting moments or different speeds by means of suitable adjustment mechanisms, for example when interacting with a linear drive. In the case of smaller tilting moments or force differences, the bearing units with play described above can be used, in particular when equalization by suitable adjustment mechanisms does not seem sufficient.

[0039] The above described embodiment is particularly advantageous if a module fixed locally relative to the die is tensioned during the extrusion process by a tensioning element and connected to a module movable relative to the die, whereby the contraction means or a linear drive included in the contraction means can be directly activated.

[0040] Finally, any motor drive capable of converting electrical energy into mechanical energy can be used as an electric motor drive, in particular a conventional electric motor, especially also having a gear mechanism, if applicable with a transmission, can be used depending on the circumstances.

[0041] Preferably, the electric motor drive is a direct drive, as has already been presented to some extent above, in particular with reference to the linear drive already described as correspondingly advantageous. On the other hand, the advantages of a direct drive as an electric motor drive can also be advantageously used in other configurations in which spindles, gear wheels, screws or nuts are envisaged to be driven for rotation as an electric motor drive, thereby making these rotary movements available with the least possible maintenance or low losses.

[0042] In particular, the electric motor drive can comprise a linear actuator as already described with reference to the linear drive, which allows low maintenance and low-loss conversion of electric energy into linear motion or linearly directed forces, as the case may be. In this context, it initially plays no role whether the linear drive or linear actuator engages a module, for example a tension rod of a tensioning element, or whether a separate device, for example a pressure rod, is driven by the associated linear actuator.

[0043] Preferably, however, the linear actuators engage the tensioning elements, and it appears to be advantageous, in particular, if each of the tensioning rods of the tensioning elements interacts with a corresponding linear actuator. In this way, a relatively compact embodiment of the extrusion press can be realised.

[0044] In this connection, it is particularly advantageous if the tensioning element comprises a stator of a linear actuator. In particular, for example, the tensioning rod of the tensioning element can be the stator of the linear actuator. In this way, the tensioning element present in any case can assume a double use, since it serves as a stator of a linear actuator and then as a counterpiece interacts with a rotor arranged, for example, on a movable cross beam or other movable module, thereby implementing the associated linear movement, and on the other hand serves as a tensioning element.

[0045] The linear drive can be equipped with a seal, whereby the risk of contamination of the linear drive is minimized. Although at first glance such extrusion presses should have a fairly low tendency to contaminate their surroundings, it has been found that the high temperatures, especially of the pressed material, and the various associated assemblies, such as, for example, shears of the remainder of the extrusion process, may nevertheless result in a relatively high degree of contamination being found around the extrusion press. By means of the seal, the moving modules involved in the application of the pressing force, such as, for example, spindles, nuts, screws or other gear mechanism elements, as well as the rotors and stators of the direct or linear drives, and especially the linear actuators, may be protected from such contamination, since it must be considered that these modules are very sensitive and prone to damage or failure to contamination, due to friction or based on magnetic or electrostatic influences.

[0046] These risks can be minimized by means of seals.

[0047] Preferably, in particular by means of a seal, the movable module is sealed towards the outside, which can be implemented for example in the form of a folded bellows or in the form of sealing bodies which can be moved relative to one another, for example tubes or hollow bodies which are moved into one another. Furthermore, conventional sealing rings or brush rings can be used in this connection.

[0048] If necessary, further limitation of contamination may be provided by supplementary methods, such as, for example, by overpressure in the enclosed space, by flushing or by supplementary brushes, if such limitation appears necessary.

[0049] The extrusion press may comprise a spindle and a nut that can be moved relative to the spindle, thereby making available the forces required in particular for the extrusion process. In such an embodiment, a seal as described above may likewise be advantageous, since the relatively large forces, the relatively large contact surface between the spindle and the nut, as well as the relatively large friction at stake in this embodiment, appear to be of particular relevance with respect to possible contamination of the spindle and the nut.

[0050] In particular, either the spindle or the nut can be rotationally driven by an electric motor drive, which can in particular be configured as a direct drive, as already explained above.

[0051] In an alternative embodiment, the spindle can be equipped with or be the tensioning element, which constitutes a very compact embodiment possible, since the contraction means can be made available directly by the spindle and the associated nut.

[0052] In particular, in such an embodiment, each tension rod is configured, as the case may be, such that the associated movable cross beam can move or have the pressing force applied as uniformly as possible.

[0053] For design implementation, it is advantageous if the tensioning element comprises at least one tensioning rod. This rod can be configured in various ways depending on the concrete implementation. Thus, for example, rigid rods as ribs arranged parallel to one another are known as tensioning rods. Similarly, cables are also used.

[0054] If applicable, supporting elements, such as for example cables or tubes enclosing ribs, are additionally used between the modules connected by the tensioning rods. In this connection, depending on the concrete implementation, the tensioning rods can be constructed in one piece or in multiple pieces. In particular, clamping elements or clamping screws or wedges or similar devices can also be components of the tensioning elements, thereby ensuring a defined distance between the modules connected to the tensioning rods and a sufficient possibility of absorbing the tension forces that arise.

[0055] In this connection, it is already known that the tensioning element or tensioning rod can take on further functions within the scope of the extrusion press. For example, a movable module, such as a movable cross beam or a receiver, can be guided or actually driven on the tensioning rod. The same applies to the extrusion residue shears, which can be guided or actually driven by the tensioning element or one or more tensioning rods if they need to be moved parallel to the pressing force direction.

[0056] In particular, the tensioning element can comprise two, three or four tensioning rods, which are preferably arranged symmetrically with respect to the resulting pressing forces. In this connection, point symmetry or mirror symmetry is particularly possible. In this way, the most uniform possible distribution of the pressing forces on the tensioning rods and thus also on the modules stressed by the pressing forces can be made possible.

[0057] In this way, the tensioning elements can be tensionally engaged with the die cross beam during the extrusion process, especially if the die cross beam is a module fixed in position relative to the die. In particular, optionally the tensioning rods can be tensionally engaged with the die cross beam during the extrusion process, so that forces acting on the die, and therefore also on the die cross beam, can be tensionally transmitted by the tensioning elements or by the tensioning rods, depending on the situation.

[0058] Additionally or alternatively, the tensioning element can engage with the counter beam with tension during the extrusion process. This is advantageous, especially if the counter beam is a module that is fixed in position relative to the die. The same applies to the tensioning rod. With such an embodiment, there is the possibility that the counter beam can absorb forces directed in the opposite direction to the pressing force and counteract them by the tensioning element.

[0059] In particular, if the tensioning element acts together with the contraction means, it may be advantageous when the tensioning element, as a module which can be moved with tension relative to the mattress during the extrusion process, engages with a movable cross beam with tension. In this way, the movable cross beam can be pulled against the die or against a cross beam for the die, so that a pressing force against the die can be applied by the movable cross beam, depending on the situation. Such an embodiment has been found to be particularly compact.

[0060] As already indicated above, the module to which the force is applied can be guided over at least one movable cross beam, which is the case for example for a punch of a direct press or a press-down plate or a direct press.

[0061] Generally, the movable cross beam is guided on the extrusion press in a particularly suitable manner, since it is supposed to perform the function of moving as a cross beam. In particular guide rails may serve for this purpose. Modules of tensioning elements, such as tensioning rods, or spacers, for example space-maintaining tubes, often serve as such guides, along which the movable cross beam can move. It should be understood that in alternative embodiments, separate guides can also be provided. These guides can also serve as part of the drive for such modules, depending on the concrete implementation, for example for the targeted movement of the receptacles.

[0062] In particular, the force-applied module may be the movable cross beam itself, it being understood that the movable cross beam may also be a component of the force-applied module, for example if not only the movable cross beam but also the punch or the sealing plate are defined as components of the force-applied module.

[0063] In particular, in the case of a direct press, the module to which the force is applied and which can be moved relative to the die can be an extrusion punch or can hold an extrusion punch, as already indicated above. In the case of an indirect press, the module to which the force is applied and which can be moved relative to the die can be, for example, a press-down plate or can hold a press-down plate. Similarly, as already explained above, the extrusion punch or the press-down plate can be components of the module to which the force is applied and which can be moved relative to the die.

[0064] In some specific embodiments, the extrusion punch may be constructed in one piece with the module to which the force is applied and which can be moved relative to the die.

[0065] In particular, the extrusion press can be a metal extrusion press capable of pressing a metal block through a die, for example, wires, rods, tubes, and / or other prismatic shapes, particularly made of metal, can be produced using the extrusion press.

[0066] In this context, an "extrusion press" in this context should be understood to be a press that can serve as a base molding or shaping process.

[0067] Such extrusion presses, in particular metal extrusion presses, can work not only with, for example, metallic blocks, but also with other powder types, for example powders containing metals, ceramics and / or hard substances, graphite powders or mixtures thereof. Corresponding granules can also be considered equivalent, and for this purpose, where applicable, the powders or granules can be pre-pressed in sufficient compaction or placed in a suitable sheath that can be loaded into the receptacle of the extrusion press.

[0068] It is conceivable that plastic materials can also be processed, a process which is generally referred to as extrusion processing in the case of pure plastic materials. When pressing the plastic material, for example by means of an extrusion screw, an additional mechanical input of energy is often provided, which is not the case in the case of an extrusion press.

[0069] Preferably, profiles constructed of stainless steel or aluminum are base molded or formed using this extrusion press, although it should be understood that the use of the extrusion press of the present invention is not limited thereto, but rather can be used for a variety of products.

[0070] In this connection, the material is pressed against and through the die by an extrusion punch, a press-down plate, or a similar module with the force required for the extrusion process. The basic forming or molding process is thus carried out.

[0071] In order to actually press the material to be pressed through the die and not let it escape to the sides, the material to be pressed is surrounded by a receiver during the extrusion process. Depending on the concrete implementation, the receiver generally remains fixed in position relative to the extrusion punch or die during the extrusion process. In this connection, theoretically linked forms are also conceivable, as already explained above.

[0072] In this context, it should be understood that the term "receptacle" in this case means any module capable of holding the material to be pressed and preventing it from escaping to the sides during the extrusion process. Depending on the specific implementation, a seal is also provided for the movable cross beam, punch or press-down plate, or die, thereby forcing the material to be pressed through the die with the minimum possible losses.

[0073] The receptacle is therefore preferably a block-type receptacle into which a metallic block or a powder or granule, which is packed, pressed or placed in a suitable sheath to form a block, can be inserted for extrusion. In general, depending on the circumstances, the existing extrusion press is not filled with a bulk or flowing material, but with piece goods, i.e., blocks. It is understood that, depending on the specific process management, these blocks can be preheated in a suitable manner to facilitate the subsequent extrusion process. Likewise, depending on the specific implementation, if the heat generated during the extrusion process is not sufficient to provide sufficient flowability of the pressed material, it is possible to heat the receptacle, the sealing plate or the extrusion punch separately.

[0074] This extrusion process is advantageous when the extrusion press operates discontinuously since it is preferably filled with a block, or material to be pressed that has no flow properties.

[0075] In a specific process sequence, the receiver can or may be filled first with the material to be pressed before the extrusion process, during which the receiver is or can be emptied and then filled again with the material to be pressed for a new extrusion process.

[0076] It is to be understood that the features of the solutions described above or in the claims can also be combined where applicable, so as to achieve additional advantages, depending on the circumstances.

[0077] Further advantages, objects and characteristics of the present invention will be explained using the following description of exemplary embodiments which are also illustrated in detail in the accompanying drawings. [Brief description of the drawings]

[0078] [Figure 1] FIG. 2 is a schematic diagram of a first extrusion press having a rotating spindle and a locking nut. [Diagram 2] FIG. 1 is a schematic diagram of a second extrusion press having a rotating spindle and a fixed nut that move together. [Diagram 3] FIG. 13 is a schematic diagram of a third extrusion press having two equipment parts, also having a rotating nut and a fixed spindle. [Figure 4] FIG. 4 is a top view of the extrusion press according to FIG. 3 in the pressing direction. [Diagram 5] FIG. 1 is a perspective view showing a ball screw as an example. [Figure 6] FIG. 2 is a perspective view showing a roller gear drive unit as an example. [Figure 7] FIG. 7 is a side view of the roller gear drive according to FIG. 6; [Figure 8] FIG. 13 is a perspective view showing a plurality of roller gear drives as an example. [Figure 9] FIG. 9 is a top view of the planetary roller gear drive according to FIG. 8; [Figure 10] FIG. 4 shows a fourth extrusion press having a cardanic joint as a bearing unit. [Figure 11] FIG. 5 shows a fifth extrusion press having a socket as a bearing unit. [Figure 12] FIG. 6 shows a sixth extrusion press having retraction means with a linear drive in each example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0079] The extrusion press 10 shown in Figures 1-4 and 10-12 is in each instance suitable and intended for pressing material 11 through a die 12. In this way, wires, rods or other prismatic shapes having relatively complex cross sections can be extruded from the pressed material 11. The pressed material can include, for example, ceramic or hard materials and, where applicable, also consist of powders or granules.

[0080] For the extrusion process, the material to be pressed 11 is in each case subjected to a pressing force and pressed through a die 12 in an extrusion direction 50 .

[0081] To force the material 11 to be pressed through the die 12, a receiver 13 is provided into which an extrusion punch 14 can be forced to apply the pressing force.

[0082] The extrusion press 10 shown in the figures is in each case a direct press, in which the extrusion punch 14 acts directly on the material 11 to be pressed and follows a pressing direction 50 for the extrusion process. Alternatively, the extrusion press 10 can also be configured as an indirect press, in which the extrusion punch 14 holds in each case the die 12 and the press-down plate is moved together with the receiver 13 relative to the die 12 and the extrusion punch 14. This results in the die 12 and the extrusion punch 14, as the case may be, pushing into the receiver 13 against the pressing direction for the extrusion process.

[0083] In this exemplary embodiment, the corresponding extrusion punch 14 is held by a movable cross beam 17, which together can be moved relative to the die 12 as a module 31. It should be understood that other components can also be included in this movable module 31, where applicable, such as a connecting piece 36 and a nut cross beam 35 (see FIG. 2), which also move together. In the case of an indirect press, the press down plate as well as the movable cross beam 17 are combined into a module 31, which is movable relative to the die 12. Again, other components can also be included, where applicable, such as a nut cross beam 35 and a connecting piece 36.

[0084] The die 12 is held by a die cross beam 15, and the two form a module 32, which is fixed in position relative to the die 12. Further components, depending on the desired fineness, may also be included in this module, which remains fixed in position relative to the die 12 during the extrusion process. In the case of an indirect press, an associated extrusion punch 14 may also be included in the module 32, which is fixed in position relative to the die 12.

[0085] For the actual extrusion process, the two modules 31, 32 are moved relative to each other, so these two modules 31, 32 are the important and effective module 30 and must be moved relative to each other for the extrusion process.

[0086] In the case of this exemplary embodiment, the pressing force is applied by the electric motor drive 40, which ultimately supports itself on the die cross beam 15 with tension by means of the tensioning element 71 or tensioning rod 16, and can thereby counter the pressing force. In the case of the extrusion press 10 shown in FIGS. 1, 2, 10 and 11, the electric motor drive 40, or the spindle / nut arrangement 20 driven by the electric motor drive 40, supports itself in each case on the counter cross beam 18, on which the tensioning element 71 or tensioning rod 16 engages with tension as the case may be. In the case of the exemplary embodiment shown in FIGS. 3 and 12, by contrast, the counter cross beam 18 only has a stabilizing function. The electric motor drive 40 or the nut 22 is provided on the movable cross beam 17 in the case of the extrusion press 10 according to FIG. 3, and thereby a tension force can be transmitted to the tensioning rod 16 by means of this nut 22. In the case of the exemplary embodiment according to Fig. 12, instead of the nut 22 interacting with the spindle 21 held by the tensioning rod 16, the rotor 75 of the linear drive 73 is arranged on or configured as the movable cross beam 17. This rotor can itself be supported on the tensioning rod 16, which is configured as the stator 74 of the linear drive 73. Thereby, in the case of this exemplary embodiment, the counter cross beam 18 likewise serves only for stabilization purposes.

[0087] To apply the pressing force, the exemplary embodiment shown in each of FIGS. 1-3, 10, and 11 includes a spindle / nut arrangement 20, which includes a spindle 21 and a nut 22.

[0088] In this connection, in the case of the exemplary embodiment according to Fig. 3, the nut 22 is driven by the electric motor drive 40, whereas in the case of the exemplary embodiments according to Fig. 1, 2, 10 and 11, the spindle 21 is in each case driven by the electric motor drive 40. It should be understood that, although in the case of the exemplary embodiments according to Fig. 1, 10 and 11, the nut 22 is driven in rotation, whereas in the case of the exemplary embodiment according to Fig. 3, a rotational drive of the spindle 21 is performed, the corresponding type of drive can also be reversed, since the nut 22 is fixed in position. Finally, what matters is the relative movement between these two modules, by which the rotational movement of the electric motor drive 40 can be converted into a linear movement, in the pressing direction 50 or vice versa.

[0089] The spindle / nut arrangement 20 is configured in this case as a rolled thread 23 so that the highest possible forces can be applied with low friction. Depending on the specific embodiment, a ball screw 80 or a roller screw 90 can be advantageously used here, as will be explained below with the aid of figures 5 to 9. On the other hand, it is to be understood that in another embodiment, the spindle / nut arrangement 20 is also conventionally provided for frictional interaction between the spindle 21 and the nut 22. In this connection, a supplementary lubricating fluid, for example hydrostatic lubrication, can be provided if necessary.

[0090] A ball screw 80, which can be used as described above and is shown by way of example in Fig. 5, comprises a spindle 21 and a nut 22 configured as a ball screw nut 82, which also comprises a ball return 83 and forms a raceway 84 together with the spindle 21. Furthermore, the ball screw 80 comprises balls 81, which run in the raceway 84 and in the ball return 83 during the relative rotational movement between the nut 22 and the spindle 21.

[0091] An electric motor drive 40 drives the spindle 21 relative to the nut 22 and vice versa. Between the spindle 21 and the ball screw nut 82, the balls 81 move in a raceway 84 which moves axially during rotation of the spindle 21. The movement of the balls 81 is such that they roll down or roll away. A ball return 83 in the ball screw nut 82 returns the balls 81, thereby closing the circuit in which the balls 81 circulate.

[0092] While in the case of conventional worm gears with surfaces sliding against one another 50-90% of the introduced power is converted into heat, the ball screw 80, due to the rolling motion of the balls 81, together with its ball screw drive, experiences less friction. In this way, lower drive powers can be sufficient, which is particularly advantageous when using an electric motor drive 40. Furthermore, the overall wear, especially between the spindle 21 and the ball screw nut 82, is less.

[0093] It should be understood that such a ball screw 80, or even ball screws having different configurations, can be used for the spindle / nut arrangement 20 of other exemplary embodiments, and even alternative embodiments.

[0094] In an alternative embodiment, the roller screw 90 may also be used as the rolled threads 23 for the spindle / nut arrangement 20, or in the case of this exemplary embodiment.

[0095] Such a roller screw 90 may also be configured as, for example, a roller screw drive 97 as shown in FIGS.

[0096] 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 having annular grooves 99 run in each instance around the spindle 21. As the rollers 91 run around the spindle 21 with their grooves 99, they are subjected to relative axial movement. The correspondingly configured recirculating roller nut 92 also comprises roller returns 98. The roller returns 98 serve to lift the rollers 91 off the spindle and return them to their position.

[0097] Due to the radial and axial movement of rollers 91, recirculating roller nut 92 is configured like a cage to hold rollers 91 in place.

[0098] For this exemplary embodiment of the extrusion press 10, the roller screw 90 may also be configured as a planetary roller screw drive 93, for example as shown in FIGS.

[0099] The planetary roller screw drive 93 comprises rollers 91 with threads 94 which rotate around the spindle 21 by means of the threads 94 in a recirculating roller nut 92 which is configured as a ring. This rotation causes relative axial movement between the nut 22 and the spindle 21.

[0100] The diameters of the spindle 21, rollers 91 and recirculating roller nut 92 are selected so that the circumferential speeds of the spindle 21 and rollers 91 are matched. This synchronization is taken care of by a ring 95 integrated into the recirculating roller nut 92, which has an internal fit that engages into sprockets 96 at both ends of the rollers 91.

[0101] In the case of this planetary roller screw drive 93, the rollers 91 or roller bodies do not move longitudinally relative to the recirculating roller nut 92, in contrast to the exemplary embodiment according to Figures 5, 6 and 7, so no return mechanism is required. This can allow for higher speeds of rotation.

[0102] The roller screw 90 also allows a corresponding reduction in friction, which incidentally also applies to screws with hydrostatic nuts 65. Furthermore, the combination of the rolled thread 23 with hydrostatic bearings or the way in which the nut of the rolled thread 23 is configured hydrostatically can be used to reduce friction depending on the circumstances. It should be understood that these advantages are already correspondingly advantageous individually, especially compared to the solutions known from the prior art.

[0103] In the case of the exemplary embodiments shown in Figures 1, 2, 10 and 11, the electric motor drive 40 is in each case implemented by a direct drive, which comprises a stator 41 and a rotor 42 which rotates together with the corresponding spindle 21. It should be understood that in alternative embodiments, other drives or other types of drives can also be used, in particular transmission drives which can actually be switched, for example where applicable.

[0104] 1, 10 and 11, in which the spindle 21 in each case is moved together with the movable cross beam 17, the stator 41 is correspondingly configured longer in these exemplary embodiments than in the exemplary embodiment according to Fig. 2. Accordingly, the spindle remains fixed in position relative to the die 12, while the corresponding hydrostatic nut 65 moves together with the movable cross beam 17, whereby the stator 41 can be correspondingly configured shorter.

[0105] In this connection, the hydrostatic nut 65 is mounted on the nut cross beam 35 in the case of the exemplary embodiment according to Fig. 2 so that it floats perpendicular to the pressing direction 50. Thereby, in this way, a bearing unit 60 with play is available perpendicular to the pressing direction 50 and thus perpendicular to the forces required for the extrusion process.

[0106] It should be understood that, where applicable, it is possible to attach directly to the movable cross beam 17 or to set the nut cross beam 35 and the movable cross beam 17 directly one behind the other, while in the case of this exemplary embodiment a connecting piece 36 having a spacer function is additionally provided between the nut cross beam 35 and the movable cross beam 17.

[0107] 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, which allows the hydrostatic nut 65 to be sufficiently lubricated both in its contact with the spindle 21 and in the bearing unit 60 against the nut cross beam 35.

[0108] In particular, the hydrostatic nut 65 can be advantageously used both in the case of a spindle / nut arrangement 20 having a rotating nut 22 and in the case of a spindle / nut arrangement 20 having a non-rotating nut 22, and it appears to be much easier in the case of a non-rotating nut 22 to utilize hydrostatic bearing material where necessary, since it is possible without a rotating union or the like.

[0109] Furthermore, the exemplary embodiment according to FIG. 2 has in the region of the electric motor drive 40 a separate bearing agent pump 66 with a bearing agent container 67, by means of which hydrostatic bearings 69 can be lubricated, which can absorb the forces of the spindle 21, which are directed in particular against the pressing force, in the counter beam 18.

[0110] It is true that the bearing agent pump 66 and the bearing agent container 67 represent additional effort for hydrostatic bearings or lubrication, in particular additional hydraulic effort, which appears to be practically avoided by the use of the electric motor drive 40. On the other hand, this additional effort is not comparable to the effort and risk of using a hydrostatic drive instead of the electric motor drive 40, which is significantly less than the effort and risk of using a hydrostatic drive.

[0111] 2 also has a drive journal 49. The drive journal 49 is arranged on the side of the spindle 21 facing the electric motor drive 40 and holds the rotor 42, thereby making the electric motor drive 40 replaceable. Such an embodiment makes it possible to quickly replace the electric motor drive 40 as needed or to adapt the electric motor drive 40 to specific requirements.

[0112] On the other hand, in the case of the exemplary embodiment according to FIG. 2, the spindle 21 is also axially mounted on the counter beam 18 by means of a return bearing 26 as well as two axial bearings 27 .

[0113] In comparison with the exemplary embodiment according to Figures 1, 10 and 11, if applicable, the reverse action depicted in Figure 2 can also be implemented in the case of the exemplary embodiment according to Figures 1, 10 and 11. The same applies to the use of drive journals 49 so as to increase the flexibility with regard to the electric motor drive 40 finally used.

[0114] Furthermore, the floating bearings of the hydrostatic nut 65 in the exemplary embodiment according to Fig. 2 can be used in the case of the embodiments according to Figs. 1, 10 and 11. However, they implement alternatives in this connection, which can also be used in the case of the exemplary embodiment according to Fig. 2 as well.

[0115] Thus, the extrusion press 10 according to FIG. 1 makes use of mounting the spindle 21 on the movable cross beam 17 by means of an axially acting roller bearing 25 and also by means of an axially acting return bearing 26, whereby a bearing unit 60 is also available, allowing play perpendicular to the pressing direction 50 or perpendicular to the force applied for the extrusion process.

[0116] The exemplary embodiment according to Fig. 10 uses at this point a cardanic joint 61. In response to the pulling and pushing, the sliding mounting of this cardanic joint is not shown separately in this exemplary embodiment, but the cardanic joint 61 also provides play perpendicular to the pressing direction 50 or to the force applied for the extrusion process. Instead of the sliding mounting, roller bearings can also be used if applicable.

[0117] In particular, in order to utilize the play perpendicular to the pressing direction 50 or to the force required for the extrusion process, the device according to Fig. 11 uses a socket 62 formed in a suitable manner, which thus allows a corresponding play perpendicular to the force applied for the extrusion process or to the pressing direction 50. In the case of this exemplary embodiment, the return stroke is also performed by a sliding bearing (not numbered). Instead of the sliding bearing, a roller bearing can also be used. It is further understood that these solution approaches can also be implemented in a suitable manner in the case of the other exemplary embodiments.

[0118] In the case of the exemplary embodiments according to FIGS. 3 and 12, contraction means 70 are provided in each case, which cause the tensioning element 71 to contract.

[0119] In this regard, in the case of these exemplary embodiments according to Figures 3 and 12, in each instance the individual tensioning rods 16 are contracted in terms of their effectiveness, since the point at which the force directed against the pressing force is absorbed is moved closer to the module 32 fixed in a predetermined position relative to the die 12.

[0120] This can in particular be achieved by the starting point on the tensioning rod 16 being moved accordingly, which can be achieved by the contraction means 70 correspondingly moving the nut 22 (see FIG. 3) or the rotor 75 (see FIG. 12) along the tensioning rod, which can be configured as a spindle 21 (see FIG. 3) or as a stator 74 (see FIG. 12).

[0121] It should be understood that in alternative embodiments, the manner of effect of the spindle 21 or the stator 74 on the one hand, and the nut 22 and the rotor 75 on the other hand, can be interchanged, e.g., that the spindle 21 rotates and the nut 22 is held in place. Furthermore, for example, the tension rod 16 can be configured as the rotor of the linear drive 73, and vice versa, the stator of the linear drive 73 can be provided on the movable cross beam 17.

[0122] In the case of the exemplary embodiment according to Figures 3 and 12, the contraction means 70 or the individual drive elements of the electric motor drive 40 are provided in the partial device 24 depending on the arrangement of the tensioning rod 16. It is to be understood that in particular the linear drive 73 can also be used, when applicable, in the case of the devices according to Figures 1, 2, 10 and 11, and that the stator 74 and the rotor 75 can be used instead of the spindle 21 or the nut 22, depending on the specific requirements.

[0123] In particular, the linear drive 73 as shown in Fig. 12 can be configured as a linear actuator. In particular, in the case of such an embodiment, there is a risk due to the influence of magnetic effects, but also possibly electrical or electrostatic effects, which may lead to a significant degree of contamination. For this reason, in the case of the exemplary embodiment according to Fig. 12, a seal 76 in the form of a folding bellows 77 is provided.

[0124] It should be understood that in alternative embodiments, other seals may be provided in place of the folded bellows 77, so long as they are suitable for sealing the critical areas.

[0125] It should also be understood that in the case of other embodiments, which may prove advantageous, for example in the electric motor drive 40 of the exemplary embodiment according to Figures 1, 2, 10 and 11, corresponding sealing parts can be provided at suitable places, if they are direct drives or on the friction surfaces of the spindle 21 or the nut 22. [Explanation of symbols]

[0126] 10. Extrusion press 11 Pressed material 12 Die 13 Receptor 14 Extrusion punch 15 Die cross beam 16 Tension Rod 17 Movable crossbeam 18 Counter beam 20 Spindle / Nut Unit 21 Spindle 22 Nut 23 Rolled thread 24 Partial device 25 Roller bearing of spindle 21 26 Return bearing 27 Axial bearing of spindle 21 30 Modules 31 Module that can be moved relative to the die 12 32 Module fixed in position relative to die 12 35 Nut cross beam 36 Connecting Piece 40 Electric motor drive unit 41 Stator 42 Rotor 49 Driving journal 50 Press Direction 60 Bearing unit 61 Cardanic Joint 62 Sockets 65 Hydrostatic nut 66 Bearing material pump 67 Bearing lubricant container 69 Hydrostatic bearings 70 Contraction means 71 Tension element 73 Linear drive unit 74 Stator of linear drive unit 73 75 Rotor of linear drive unit 73 76 Sealing part 77 Folding bellows 80 Ball screw 81 Ball 82 Ball screw nut 83 Ball return section 84 Raceway 90 Roller screw 91 Lola 92 Recirculating roller nut 93 Planetary roller screw drive 94 Thread 95 Ring 96 Sprocket 97 Roller screw drive 98 Roller return part 99 Groove

Claims

1. An extrusion press (10) for extruding a material (11) to be pressed through a die (12), comprising: a receiver (13) for holding the material to be pressed (11) and a module (31) that can be moved relative to the die (12), said module (31) being acted upon with the forces required for said extrusion process by an electric motor drive (40) during said extrusion process, 1. An extrusion press (10), characterized in that the electric motor drive (40) is connected to the module (31) movable relative to the die (12) by a bearing unit (60) having a play perpendicular to the force and having at least two degrees of freedom.

2. 2. The extrusion press (10) according to claim 1, characterized in that the electric motor drive (40) drives contraction means (70) for contracting, during the extrusion process, an area of ​​a tensioning element (71) which bears under tension and by tension opposes the forces necessary for the extrusion process.

3. 2. The extrusion press (10) of claim 1, characterized in that the electric motor drive (40) is a linear drive (73) and moves a module (32), which is fixed in a predetermined position with respect to the die (12) during the extrusion process, and a module (31), which is movable with respect to the die (12) during the extrusion process, relative to each other during the extrusion process.

4. 2. Extrusion press (10) according to claim 1, characterized in that the bearing unit (60) is a cardanic joint (61) and / or comprises a socket (62) having two degrees of freedom.

5. 3. An extrusion press (10) according to claim 2, characterized in that the contraction means (70) comprises a linear drive (73) and the module (32) fixed in a predetermined position relative to the die (12) is connected by tension to the module (31) movable relative to the die (12) by means of the tensioning element (71) during the extrusion process.

6. 2. The extrusion press (10) of claim 1, characterized in that the electric motor drive (40) is a direct drive and / or comprises a linear actuator.

7. 2. An extrusion press (10) according to claim 1, characterised in that it comprises a spindle (21) and a nut (22) which is axially movable relative to said spindle (21).

8. 3. Extrusion press (10) according to claim 2, characterized in that the tensioning element (71) comprises at least one tensioning rod (16).

9. 3. An extrusion press (10) according to claim 2, characterized in that the tensioning element (71) engages a die cross beam (15) as the module (32) fixed in a predetermined position relative to the die (12) and / or a counter cross beam or movable cross beam (17) as the module (31) movable relative to the die (12).

10. 2. An extrusion press (10) according to claim 1, characterized in that the module (31) to which the force is applied is guided by at least one movable cross beam (17) or the module (31) is the movable cross beam (17).

11. 2. The extrusion press (10) of claim 1, characterized in that the module (31) to which the force is applied and which is movable relative to the die (12) is an extrusion punch (14) or holds the extrusion punch (14).

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