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). While the extrusion process is taking place, at least one module of the extrusion press can be influenced with the force required for the extrusion process by an electric motor drive. [Background technology]

[0002] German Patent No. 102015116002 discloses an extrusion press for pressing a material through a die, which has a receptacle for holding the material to be pressed and an extrusion punch that can be moved relative to the die. The pressing force is applied by a hydraulic drive. Such a device has proven to be particularly effective at applying very large pressing forces.

[0003] Patent documents 6,143,142 and EP 3,470,146 also disclose extrusion presses for pressing materials, which have a receptacle for holding the material to be pressed and an extrusion punch that can be moved relative to a die, and in which the pressing force is applied using an electric motor. Such devices are considered particularly suitable for extrusion presses in which lower pressing forces are to be applied, and are equipped with a nut / spindle, in which the electric motor drives the nut to rotate, which in turn acts on a spindle attached to the extrusion punch or some other module that can apply the force required for the extrusion process. The rotary movement of the electric motor is thereby converted into linear movement, and the pressing force is applied, causing the extrusion punch or the corresponding module to move 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 an electric motor drive to make the necessary force 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 force for extrusion available and to achieve good extrusion results even when using an electric motor drive, the present invention proceeds from the basic inventive idea in implementing design measures that allow the most uniform and accurate 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 to extrude the material to be pressed through a die, which has a receptacle for holding the material to be pressed 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 the module that can be moved relative to the die by a bearing unit with play perpendicular to the force, the force required for the extrusion can be applied to this module 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 adequately absorbed. On the other hand, the force applied by the electric motor drive to the movable module or to a 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 a way that reduces as little as possible.

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

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

[0012] In this connection, it initially plays no 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 extrusion, and having a play perpendicular to the force can be used as a bearing unit with play perpendicular to the force. In particular, the bearing unit can be provided 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 be provided with a cardanic joint, which, due to its characteristics, can transmit forces, in other words, press forces, along the respective rotation axis and tilt with a perpendicular component to the forces. On the other hand, the bearing unit can be provided with a socket, which has at least one degree of freedom, preferably at least two degrees of freedom. Depending on the circumstances, this degree of freedom 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 in the direction 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 allowing the connections of possible gear mechanisms, such as the spindle drive, to be correspondingly relieved of stress from forces occurring perpendicular 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 that can be moved relative to the die and that can be influenced by an electric motor drive with the force required for extrusion during the extrusion process, can be characterized in that the electric motor drive drives a contraction means for contracting the area of ​​the tensioning element that is subjected to tension during the extrusion process, the tensioning element counteracting the force required for the extrusion by tension in order to achieve a good extrusion result. This also represents a design measure, when suitably configured, that allows the most uniform and precise force effect of the pressing force on the pressed material possible.

[0017] Thus, extrusion presses typically 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, in this regard, the pressing force is applied by moving the movable cross beam toward the die in the direction of extrusion, or vice versa.

[0018] To completely prevent the pressed material from escaping radially or from accidentally escaping out of the die, a receptacle is generally provided, which can resist the radial expansion of the pressed material during the extrusion process. Preferably, the receptacle is sealed in a suitable manner against the die or against the movable crossbeam or punch, so that the pressed material can resist the pressing force applied by the relative movement of the movable crossbeam with respect to the die, since the pressed material can only exit through the die.

[0019] In this context, the term "receptacle" should therefore be 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 that work indirectly, in which the die itself is generally arranged on a punch, which is optionally hollow so as not to prevent the material from passing through the die. In such embodiments, 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 receiving vessel.

[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 into the receiver during the extrusion process.

[0022] It should be understood that mixed configurations of direct and indirect presses are also possible and ultimately do not exist or are rarely present on the market.

[0023] To counteract the applied pressing force, extrusion presses typically have a press frame, which includes a die beam on one side and a counter beam on the other. They are connected to each other by tie rods, so that a corresponding drive, such as an electric motor drive, can support itself on the counter beam and apply a pressing force to the movable beam. In such an embodiment, the corresponding force between the counter beam and the movable beam can be applied by a spindle, by multiple spindles, or by one or more shoe pistons, which ultimately results in the desired movement of the movable beam.

[0024] However, the force is not applied to the movable cross beam, but rather in the direction of the die movement, which is supposed to be responsible for the extrusion process. It is also conceivable to pull the movable cross beam directly against the die cross beam, which can be achieved in particular by means of a tension rod. In such an embodiment, it is particularly possible to use a contraction means to contract the tension rod as needed, and to apply a pressing force or a movement of the movable cross beam by this contraction process.

[0025] In such an embodiment, it may be possible to do without a counter beam at all. Depending on the specific 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 section 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 located opposite the die beam in each case. However, if a contraction means is provided, for example, on the die beam, so that the tension rod is driven away from 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 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 outwardly protruding tension rod.

[0026] While the contraction means can thus contract the tensioned region of the tensioning element of the extrusion press, it is not necessary that the tensioning element itself be contracted by the contraction means as the situation demands. Such contraction would generally be very complicated in terms of construction, in particular because a corresponding contraction of the tensioning element would have to take place in tensioned conditions, and a new extension of the tensioning element would be necessary for a new extrusion process after the current extrusion process. Therefore, it would generally be easier if the contraction means only contracted the tensioned region of the tensioning element and if this was implemented in a structurally 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 leads to a contraction of the distance between the modules connected to each other by the tensioning element and to the application of tension to the tensioning element during the extrusion process. This may possibly be a module fixed in position relative to the die or a module that is optionally movable, in particular a module that is movable relative to the die, as already mentioned above.

[0028] In particular, apart from the combination of the above-mentioned features, an extrusion press for extruding a material to be pressed through a die, having a receptacle for holding the material to be pressed and a module that can be moved relative to the die and that can apply the force required 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 that moves modules that are fixed in position relative to the die during the extrusion process and modules that are movable relative to each other 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 that, depending on the circumstances, allows a more uniform and precise possible force effect on the material to be pressed.

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

[0030] In this context, the term "module movable relative to the die" is therefore understood to mean any module of the extrusion press that can be moved relative to the die. Preferably, this module is acted upon by at least a portion 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 the corresponding movable module.

[0031] Preferably, the movable module is driven by a drive, in particular an electric motor drive. In this connection, it should 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 an extrusion press that remain or can remain fixed in position relative to the die during the extrusion process can be considered locally fixed modules in this context. In particular, for example, a die 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. Generally, if the drive acts on the counter beam, supporting itself on the counter beam and moving it on the movable beam, the tension rod and counter beam can also be considered locally fixed modules relative to the die during extrusion. On the other hand, if, for example, the counter beam itself moves during the extrusion process, i.e., if the counter beam serves as a positioning element for the end of the tie rod, then the end of the tie rod also moves relative to the die, and they use, for example, the aforementioned contraction means, then the counter beam is not considered to be a locally fixed module relative to the die. 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 with the movable cross beam and therefore cannot be considered 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 carried out structurally precisely and in particular with reduced possibility of using additional gearing elements or without additional 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. Specifically, direct drives typically also provide linear motion and utilize a gearing element or elements, such as a nut, screw, or spindle, which is preferably not required for linear drives.

[0037] In particular, torque motors or motor spindles, for example, 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 locally fixed modules relative to the die during the extrusion process, preferably with 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 that are movable relative to the die during the extrusion process. Such an embodiment has a particularly compact structure 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 can compensate for any tilting moments or different speeds by means of a suitable adjustment mechanism, for example, when interacting with a linear drive. In cases where the tilting moments or force differences are smaller, the above-described bearing units with play can be used, especially when equalization by a suitable adjustment mechanism is deemed insufficient.

[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 with a transmission, especially also with a gear mechanism, if applicable.

[0041] Preferably, the electric motor drive is a direct drive, as has already been mentioned above to some extent, 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 used advantageously 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 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 electrical energy into linear motion or linearly directed force, depending on the circumstances. In this context, it initially plays no role whether the linear drive or linear actuator engages a module, for example a tensioning 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 tensioning rod of the tensioning elements interacts with a corresponding linear actuator. In this way, relatively compact embodiments of the extrusion press can be realized.

[0044] In this context, 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 dual use, since it serves as a stator of a linear actuator and then as a counterpiece, interacting with a rotor arranged, for example, on a movable cross beam or other movable module, thereby performing the associated linear movement, and on the other hand serves as a tensioning element.

[0045] The linear drive can be equipped with seals, which minimize the risk of contamination of the linear drive. At first glance, such extrusion presses should have a fairly low tendency to contaminate their surroundings. However, it has been found that the high temperatures of the pressed material, in particular, and the various associated components, such as shears from the extrusion process, can still result in a relatively high degree of contamination being found around the extrusion press. The seals can protect the moving modules involved in applying the pressing force, such as spindles, nuts, screws, or other gearing elements, as well as the rotors and stators of the direct or linear drive, and especially the linear actuators, from such contamination. This is because these modules are highly sensitive and prone to damage or failure due to friction or magnetic or electrostatic influences.

[0046] These risks can be minimized by sealing.

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

[0048] If necessary, further limitation of contamination can be provided by supplementary methods, such as by overpressure in the sealed space, by flushing or by supplementary brushes, if such limitation is deemed 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 for the extrusion process in particular. In such an embodiment, a seal as described above may also be advantageous, since the relatively large forces, the relatively large contact surface between the spindle and the nut, and the relatively large friction involved in this embodiment are likely to be particularly relevant with regard to possible contamination of the spindle and the nut.

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

[0051] In an alternative embodiment, the spindle can be provided 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 so that the associated movable cross beam can move or have the pressing force applied as uniformly as possible, depending on the circumstances.

[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 specific implementation. Thus, for example, rigid rods as ribs arranged parallel to one another are known as tensioning rods. Cables can also be used.

[0054] If applicable, additional support elements, such as tubes enclosing cables or ribs, are used between the modules connected by the tensioning rods. In this regard, depending on the specific implementation, the tensioning rods can be constructed in one piece or in multiple pieces. In particular, clamping elements or clamping screws, 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 sufficient capacity to absorb the resulting tension forces.

[0055] In this regard, it is already known that tensioning elements or tensioning rods can take on additional functions within the extrusion press. For example, movable modules, such as movable cross beams or receivers, can be guided or actually driven on the tensioning rods. The same applies to extrusion residue shears. If this extrusion residue shear needs to be moved parallel to the direction of the pressing force, it can be guided or actually driven by the tensioning element or one or more tensioning rods.

[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 force. Point symmetry or mirror symmetry is particularly possible in this regard. This allows for the most uniform possible distribution of the pressing force on the tensioning rods, and thus also on the modules subjected to the pressing force stress.

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

[0058] Additionally or alternatively, the tensioning element can engage 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 of the pressing force and counteract them with the tensioning element.

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

[0060] As already indicated above, the force-applied module can be guided over at least one movable cross beam, as 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 assumed 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 other embodiments, separate guides may also be provided. These guides may also serve as part of the drive for such modules, depending on the specific 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 or 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 a component 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 a module to which 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, wire, rod, tube, 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 is understood to be a press that can serve a basic forming or molding process.

[0067] Such extrusion presses, in particular metal extrusion presses, can work not only with, for example, metal blocks, but also with other powder types, such as powders containing metals, ceramics and / or hard materials, 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-packed and pressed 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 in the case of pure plastic materials. When pressing plastic materials, for example by means of an extrusion screw, additional mechanical input of energy is often used, whereas this is not the case in extrusion presses.

[0069] Preferably, a profile constructed of stainless steel or aluminum is 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 regard, the material is pressed against and through the die by an extrusion punch, press-down plate, or similar module with the force required for the extrusion process. The basic forming or molding process is thus carried out.

[0071] To actually press the material through the die and prevent it from escaping to the sides, the material is surrounded by a receptacle during the extrusion process. Depending on the specific implementation, the receptacle generally remains fixed in position relative to the extrusion punch or die during the extrusion process. In this regard, 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 may also be 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] Thus, the receptacle is preferably a block-type receptacle into which a metal block or a powder or granular material can be inserted for extrusion, which is then packed, pressed, or placed in a suitable sheath to form a block. Generally, depending on the circumstances, existing extrusion presses are not filled with bulk or flowing material, but with piece goods, i.e., blocks. It should be understood that, depending on the specific process, these blocks can be preheated in a suitable manner to facilitate the subsequent extrusion process. Similarly, depending on the specific implementation, if the heat generated during the extrusion process is not sufficient to provide sufficient flowability for the pressed material, the receptacle, the sealing plate, or the extrusion punch can be heated separately.

[0074] This extrusion process is advantageous when the extrusion press operates discontinuously, as the material to be pressed is preferably filled in blocks or non-flowable materials.

[0075] In a specific processing sequence, the receiver can or may be first filled with the material to be pressed before the extrusion process, and during the extrusion process 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 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 explanation of the drawings]

[0078] [Figure 1] FIG. 1 is a schematic diagram of a first extrusion press having a rotating spindle and a locking nut. [Figure 2] FIG. 10 is a schematic diagram of a second extrusion press having a rotating spindle and a locking nut that move together. [Figure 3] 10 is a schematic diagram of a third extrusion press having two parts, also having a rotating nut and a fixed spindle. FIG. [Figure 4] 4 is a top view of the extrusion press according to FIG. 3 in the pressing direction. [Figure 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 unit according to FIG. 6. [Figure 8] FIG. 10 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. 10 shows a fifth extrusion press having a socket as a bearing unit. [Figure 12] 6 shows a sixth extrusion press with retraction means in each case comprising a linear drive. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0079] The extrusion press 10 shown in Figures 1-4 and 10-12 is suitable and intended in each instance for pressing material 11 through a die 12. In this manner, 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 powders or granules.

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

[0081] To force the material 11 to be pressed through the die 12, a receptacle 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 the die 12 in each case, and the press-down plate is moved together with the receiver 13 relative to the die 12 and the extrusion punch 14, which results in the die 12 and the extrusion punch 14 optionally 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, such as a connecting piece 36 and a nut cross beam 35 (see FIG. 2), which move together, can also be included in this movable module 31, if applicable. In the case of an indirect press, the press down plate and the movable cross beam 17 are combined into a module 31, which is movable relative to the die 12. Again, other components, such as a nut cross beam 35 and a connecting piece 36, can also be included, if applicable.

[0084] The die 12 is held by a die crossbeam 15, and the two form a module 32, which is fixed in position relative to the die 12. Other components may also be included in this module, depending on the desired fineness, which remains fixed in position relative to the die 12 during the extrusion process. In the case of an indirect press, the 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, and therefore these two modules 31, 32 are the key effective module 30 and must be moved relative to each other for the extrusion process.

[0086] In this exemplary embodiment, the pressing force is applied by the electric motor drive 40, which ultimately supports itself on the die cross beam 15 under tension by means of the tensioning element 71 or tensioning rod 16, thereby counteracting the pressing force. In the extrusion press 10 shown in FIGS. 1, 2, 10, and 11, the electric motor drive 40, or the spindle / nut device 20 driven by the electric motor drive 40, supports itself in each case on the counter beam 18, on which the tensioning element 71 or tensioning rod 16, as the case may be, engages under tension. In the exemplary embodiment shown in FIGS. 3 and 12, by contrast, the counter beam 18 only has a stabilizing function. The electric motor drive 40 or the nut 22 is mounted on the movable cross beam 17 in the case of the extrusion press 10 according to FIG. 3, so that tension can be transmitted to the tensioning rod 16 by means of this nut 22. 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 a movable cross beam 17. This rotor can itself be supported on the tensioning rod 16, which in turn is configured as a stator 74 of the linear drive 73. Thereby, in this exemplary embodiment, the counter 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 exemplary embodiment according to Fig. 3, the nut 22 is driven by the electric motor drive 40, while in the exemplary embodiments according to Figs. 1, 2, 10 and 11, the spindle 21 is driven in each case by the electric motor drive 40. It should be understood that, although in the exemplary embodiments according to Figs. 1, 10 and 11 the nut 22 is driven in rotation, while in the exemplary embodiment according to Fig. 3 the spindle 21 is driven in rotation, the corresponding types of drives can also be reversed, since the nut 22 is fixed in position. Ultimately, what matters is the relative movement between these two modules, by means of 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 should be understood that in other embodiments, 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 that can be used as described above and is shown by way of example in Figure 5 comprises a spindle 21 and a nut 22 configured as a ball screw nut 82, which also comprises a ball return portion 83 and forms a raceway 84 together with the spindle 21. Furthermore, the ball screw 80 comprises balls 81 that run through the raceway 84 and the ball return portion 83 during 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, balls 81 move in a raceway 84, which moves axially during rotation of the spindle 21. The motion of the balls 81 is by rolling down or rolling away. A ball return 83 in the ball screw nut 82 returns the balls 81, thereby closing the circulation path through which the balls 81 circulate.

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

[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 can also be used as the rolled thread 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, roller screw drive 97 comprises spindle 21 and nut 22 configured as a recirculating roller nut 92. Rollers 91 having annular grooves 99 run around spindle 21 in each instance. As rollers 91 run around spindle 21 with their grooves 99, they undergo relative axial movement. Correspondingly configured recirculating roller nut 92 also comprises roller returns 98. Roller returns 98 serve to lift rollers 91 from the spindle and return them to their desired 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, as shown, for example, in FIGS.

[0099] Planetary roller screw drive 93 includes rollers 91 with threads 94 that rotate around spindle 21 using threads 94 in a recirculating roller nut 92 configured as a ring. This rotation causes relative axial motion between nut 22 and spindle 21.

[0100] The diameters of the spindle 21, rollers 91, and recirculating roller nut 92 are selected to match the circumferential speeds of the spindle 21 and rollers 91. This synchronization is provided by a ring 95 integrated into the recirculating roller nut 92, which has internal engagements that engage in 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, which can allow for higher speed 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 a hydrostatic bearing or a method in which the nut of the rolled thread 23 is configured hydrostatically can be used to reduce friction depending on the situation. It should be understood that these advantages are already correspondingly advantageous individually, especially compared to solutions known from the prior art.

[0103] 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, for example, transmission drives which can actually be switched, where applicable.

[0104] 1, 10 and 11, the spindle 21 in each case is moved together with the movable cross beam 17, so that in these exemplary embodiments the stator 41 is correspondingly longer 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 shorter.

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

[0106] It should be understood that, where applicable, it is possible to attach the nut cross beam 35 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 in both spindle / nut assemblies 20 having a rotating nut 22 and in spindle / nut assemblies 20 having a non-rotating nut 22, and it appears that it is significantly easier in the case of a non-rotating nut 22 to utilize hydrostatic bearing material where necessary, since it is possible to do without a rotating union or the like.

[0109] Furthermore, the exemplary embodiment according to FIG. 2 has a separate bearing agent pump 66 with a bearing agent container 67 in the area of ​​the electric motor drive 40, by means of which hydrostatic bearings 69 can be lubricated, which can absorb the forces of the spindle 21 directed against the pressing force, in particular, on 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 bearing or lubrication, in particular additional hydraulic effort, which is likely to be avoided in practice by using the electric motor drive 40. On the other hand, this additional effort is incomparable to the effort and risk involved in using a hydrostatic drive instead of the electric motor drive 40, which is significantly less than the effort and risk involved in using a hydrostatic drive.

[0111] 2 also has a drive journal 49. The drive journal 49 is configured on the side of the spindle 21 facing the electric motor drive 40 and holds the rotor 42, 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] Compared to 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 ultimately 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 regard, which can also be used in the case of the exemplary embodiment according to Fig. 2.

[0115] Thus, the extrusion press 10 according to FIG. 1 makes use of the spindle 21 being attached to 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 likewise a bearing unit 60 is 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 a cardanic joint 61 at this point. The sliding mounting of this cardanic joint, which is not shown separately in this exemplary embodiment, corresponds to the pulling and pushing, but 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 where 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 a sliding bearing, a roller bearing could 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 contract the tensioning element 71 .

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

[0120] This can be achieved in particular 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 Figure 3) or the rotor 75 (see Figure 12) along the tensioning rod, which can be configured as a spindle 21 (see Figure 3) or as a stator 74 (see Figure 12).

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

[0122] In the case of the exemplary embodiments according to Figures 3 and 12, the respective drive elements of the retraction means 70 or the electric motor drive 40 are provided in the sectional 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 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 Figure 12 can be configured as a linear actuator. In particular, in the case of such an embodiment, there is a risk of magnetic, but also possibly electrical or electrostatic, effects, which can lead to a significant degree of contamination. For this reason, in the case of the exemplary embodiment according to Figure 12, a sealing part 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 bellows 77, as long as they are suitable for sealing the critical areas.

[0125] It should also be understood that in other embodiments, it may be advantageous, for example in the electric motor drive 40 of the exemplary embodiment according to Figures 1, 2, 10 and 11, whether they are direct drives or on the friction surfaces of the spindle 21 or nut 22, that corresponding seals can be provided at suitable locations. [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 Device 21 Spindle 22 Nut 23 Rolled threads 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 place relative to die 12 35 Nut cross beam 36 Connecting Piece 40 Electric motor drive unit 41 Stator 42 rotor 49 Drive journal 50 Press Direction 60 Bearing unit 61 Cardanic Joint 62 sockets 65 Hydrostatic nut 66 Bearing agent pump 67 Bearing lubricant container 69 Hydrostatic bearing 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 part 84 Raceway 90 Roller screw 91 Laura 92 Recirculating roller nut 93 Planetary roller screw drive unit 94 threads 95 Ring 96 sprocket 97 Roller screw drive unit 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 (11) to be pressed, and a module (31) that can be moved relative to the die (12), said module (31) being acted upon by an electric motor drive (40) during the extrusion process with the force required for said extrusion; wherein 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; The extrusion press (10) is characterized in that the electric motor drive (40) drives a contraction means (70) for contracting, during the extrusion process, the area of ​​the tensioning element (71) that bears under tension and by tension opposes the force required for the extrusion process.

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

3. 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) with two degrees of freedom.

4. 2. The extrusion press (10) according to claim 1, 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 the tensioning element (71) during the extrusion process.

5. 2. Extrusion press (10) according to claim 1, characterized in that the electric motor drive (40) is a direct drive and / or comprises a linear actuator.

6. 2. An extrusion press (10) according to claim 1, characterized in that it comprises a spindle (21) and a nut (22) that can be moved axially relative to said spindle (21).

7. 2. Extrusion press (10) according to claim 1, characterized in that the tensioning element (71) comprises at least one tensioning rod (16).

8. 2. The extrusion press (10) according to claim 1, characterized in that the tensioning element (71) engages with a die cross beam (15) as the module (32) fixed in a predetermined position relative to the die (12) and / or with a counter cross beam or movable cross beam (17) as the module (31) movable relative to the die (12).

9. 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).

10. 2. The extrusion press (10) of claim 1, wherein 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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