EP1754595B1 - Drive module for press and method for providing a range of presses - Google Patents

Description

The invention relates to a press drive module and a method for providing a press series.

In the past, the plungers of large mechanical presses were usually connected by connecting rods to an eccentric drive, which in turn was driven by a drive motor and a flywheel at a relatively uniform speed. Because such drives impose certain limitations on the travel / time history of the plunger movement, efforts have been made to drive the plunger, for example, by means of a servomotor, with the path / time curve of the plunger motion then set relatively freely by the appropriate control of the servomotor could be. For example, the disclosed DE 41 09 796 C2 the drive of the plunger via a connecting rod and an eccentric, which is driven by a servomotor. The servomotor can run forwards and backwards and can be specifically accelerated and decelerated.

From the same document, the drive of the plunger on a toggle mechanism is apparent, the toggle mechanism in turn via a connecting rod and an eccentric of a servomotor is driven. Even with this configuration, desired path / time profiles can be set within wide limits.

The U.S. Patent No. 6,041,699 also discloses a ram drive a press by means of servo motor via toggle mechanism. To drive the toggle mechanism serve a Schraubspindelgetriebe and servomotors.

From the JP 2000 343283 In addition, the drive of a press ram via screw jacks is known, which are actuated by servomotors. Here too, a largely permissive determination of the path / time course of the plunger movement can be achieved.

DE 43 19 289 A1 describes a press drive module for a press ram according to the preamble of claim 1 for generating a drive movement and a pressing force between a first output to be connected to a press frame and a second output connected to the press ram. A first drive device, which is connected to at least one of the at least two outputs, is characterized by a first force / displacement characteristic. At least one second drive device connected to the other of the at least two outputs is characterized by a second force / displacement characteristic. The force / displacement characteristics of the at least two drive devices are set differently. The press drive module forms a structural unit with the press frame. The one drive device is formed by a drive cylinder, which sits on a gear block and can perform a lifting movement of the press ram relative to the gear block. The other drive device is formed by Verstellspindelantriebe which are rotatably mounted on the press frame and driven by motors which are associated with the press frame. This drive device moves the gear block together with the press ram in the stroke direction to adjust the distance between the press ram and the lower tool, for example, to adapt to different sized tools can.

US Pat. No. 6,708,609 B1 discloses a method for providing a press line comprising a plurality of presses of different pressing force, each with press drive modules for their press rams for generating a drive movement and a pressing force between a first output to be connected to a press frame and a second driven end connected to the press ram. The press drive module has a first drive device, which is connected to at least one of the outputs and which is characterized by a first force / displacement characteristic.

DE 101 58 861 A1 describes a press drive module for a press ram for generating a drive movement and a pressing force between a first output to be connected to a press frame and a second output connected to the press ram. A first drive device is connected to at least one of the at least two outputs and has a first force / displacement characteristic. The first drive means is formed by a hollow shaft gear, a spindle and a spindle nut. A second drive device, which is connected at least to the other of the at least two outputs has a second force / displacement characteristic and is as a hydraulic piston-cylinder drive executed. The two force / displacement characteristics of the at least two drive devices are set differently. The press drive module forms a structural unit.

The presented solutions each suffer from specific limitations. Are used to drive the plunger, for example, non-linear gear, such as toggle mechanism or eccentric, the plunger movement is often not as freely adjustable as desired. In addition, the entire forming force must be applied by the servomotor. The latter is particularly disadvantageous in the case of the above-mentioned drive concepts. Although non-linear gearboxes, such as toggle mechanisms or eccentric gearboxes, allow the generation of a higher force near the dead center, but only over a relatively short distance. Although the drive of the press ram by means of screw jack allows on the one hand a very revealing determination of the path / time history of the plunger movement, but it limits the achievable before reaching bottom dead center maximum force.

On this basis, it is an object of the invention to improve the optionally controllable press drive.

This object is achieved both with the press drive module according to claim 1 and with the method according to claim 14:

The press drive module according to the invention combines in itself two drive devices which have different force / displacement characteristics. This is preferably achieved by using different drive concepts. In order to can not only wide limits arbitrary path / time curves of the plunger movement can be achieved but it is also possible to use for each part of the path / time curve respectively that drive device having the just fitting characteristic. For example, a weak but rather fast drive can be used for the passage of characteristic sections, which only require a small actuating force. For the implementation of forming operations, which are usually speedy but still relatively slow to perform but with high power that drive device can be used, which applies a relatively high operating force at a relatively low speed.

In the simplest case, the two drive means united in the press drive module, e.g. be formed by servomotors with downstream transmission and different transmission ratios. The servomotors can be the same or different. Due to the different reduction, the servomotors work, although act on the same output, at one and the same output speed in different characteristic areas, which increases the overall design freedom in terms of achievable path / time profiles of the plunger movement. In addition, the scope is increased in terms of achievable forces.

The extent given press drive module is thus versatile and can serve as a basis for the equipment of different sizes presses of a press series. On the one hand, a large range of desired forces and driving speeds can be achieved with the given press drive module be achieved. On the other hand, the press drive modules, if the non-constructive or other Praktikabilitätsgrenzen oppose, be connected in parallel in principle any number. Thus, a press ram can be driven by one or more identical press drive modules, which can be provided within a press series of different performance classes. It is also possible to provide drive modules in different power classes, with the drive modules being consistent within each power class.

By combining several drive modules of one or two or more power classes and by the large power range of each press drive module thus all presses of the press series can be equipped with the unified press drive modules. For example, a press line can be constructed, the first stage (drawing stage) has a larger number of press drive modules while the subsequent, usually less loaded, press stages are equipped with correspondingly fewer press drive modules. In the individual stages of the press line different ram-way / ZeitVerläufe and different ram strokes can be driven.

Particularly expediently, the performance classes of the provided press drive modules having a uniform maximum lift are exponentially stepped. This allows a wide variety of applications to be made possible by combining press drive modules of different performance classes. The power classes of the drive modules are determined, for example, by the maximum forces to be applied by the drive modules. Here are also the Drive modules of different power classes preferably on the same maximum stroke. This allows the combination of press drive modules of different power classes with each other for the common drive of a plunger of a press. Furthermore, the press drive modules of the different performance classes preferably have the same maximum travel speeds. This facilitates as well as the uniformly fixed maximum stroke, the parallel arrangement for common drive one and the same plunger.

The press drive modules each form structural units, which are formed separately from the press. They can thus be prefabricated and installed as a finished assembly in appropriately prepared press racks. The assembly of the press drive modules can be separated from the assembly of the press frame. This is especially important for large presses. With this concept, a manufacturing simplification can go hand in hand and the construction time of presses can be shortened.

For many purposes it is advantageous if at least one of the drive means of the press drive modules includes a variable ratio transmission. This may be, for example, a toggle mechanism, an eccentric, a combination thereof or any other transmission with variable ratio. As such, in particular gearboxes come into question, which deliver in their dead or reversal point an infinitely large force transmission or in other words a fixed support point by the force to be sustained is no longer determined by the driving servo motor but only by the load limits of the transmission.

This has e.g. in solutions meaning in which the drive means - as an alternative to the inventive solution - are arranged constructively in series. For example, a servo-driven eccentric drive can be connected in series with a hydraulic cylinder. While the eccentric drive then serves to drive the ram in areas of its movement curve with relatively little force quickly, the hydraulic drive means can be used to drive the ram for workpiece deformation slowly with great force. If the eccentric is in dead center, the servomotor remains substantially free of forces. It is thus possible with relatively weak servomotors and a relatively short-stroke hydraulic device on the one hand to produce a large movement stroke for the plunger and on the other hand, a high forming force.

This preference can also be achieved with other serially arranged drive devices.

It may be advantageous to activate the drive devices sequentially in time. The two different drive devices are thus responsible for different sections of the path / time curve of the plunger movement. In the transition region from the activation of one drive device for activating the other drive device, both drive devices can be activated overlapping.

In particular, in the case of a parallel arrangement of the two drive devices, these are preferably each common activated, complementing each other in terms of their power development.

It is advantageous if the press drive module has its own base frame, which takes over the leadership between the two drives. It may further be provided a housing in which the at least two drive means are housed. Alternatively, however, it is also possible to integrate the press drive module at least partially into the press frame. For example, one of the power take-offs may be formed as part of a press header or plunger.

The press drive modules is preferably associated with an energy store, for example a mechanical, electrical or hydraulic energy store. This minimizes the supply network load.

The press drive module can be executed in principle in a variety of ways. However, its characteristic feature in almost all embodiments is that the introduction of force from the at least two drive means belonging to the module takes place at the plunger and / or at the head piece at a common location. In addition, the press drive modules provide a fixed numerical relationship between the number of first drive means and the number of second drive means. For example, if a plunger is merely driven by drive modules of a single power class, which each have, for example, a first drive device and a second drive device respectively, then the plunger drive is generally independent of the number of press drive modules as many first drive means as second drive means available.

If press drive modules are used with e.g. a first drive means and two or more e.g. three second drive means designed and used for ram drive, here are in the example three times as much second drive means available as first drive means. If press drive modules of different power classes and with different ratios between the numbers of the first and the second drive means are used, these numerical ratios apply in groups for the press drive modules of the respectively considered performance class.

The drive means of the press drive module are preferably mechanically independent of each other, i. they can be controlled independently of each other. The synchronization of their working movement or the coordination thereof is preferably carried out electrically. The individual modules or even only their drive devices or drives can be selectively controlled depending on the design or optionally also switchable and / or force-controlled. They preferably allow a continuous adjustment of the plunger stroke during operation and a variation of the path / time characteristic of the plunger movement during operation. Force sensors can be provided in order to avoid overloading, in particular in the case of drive modules or drive devices driven in a controlled manner.

It is also possible to rigidly access the individual drive devices of a press drive module connect. Alternatively, they may be coupled together via coupling devices of arbitrarily controllable type or overrunning clutches. For example, in a parallel arrangement of two drive means, the slow drive means can be decoupled from the high-speed, when a ram travel is to go through quickly. The slow drive is then coupled again when the fast drive has moved the plunger back to the Abkuppelstelle and a slower plunger movement a large force is required.

In an alternative to the parallel arrangement according to the invention provided for a serial arrangement of two drive means in a press drive module, it is possible to brake the fast drive means with a braking device when a slow working movement is to be generated with high force. The stronger of the two drive devices is then supported not only on the first drive device but additionally or even exclusively via the brake device. The aforementioned coupling devices and brake devices can thus serve to make the plunger movement more efficient.

Further advantageous details of embodiments of the invention are the subject of the drawing, the description or claims.

Figur 1

eine Presse mit modularem Pressenantrieb in schematisierter Prinzipdarstellung,

Figur 2

ein Pressen-Antriebsmodul für die Presse nach Figur 1 in schematisierter Darstellung,

Figur 3

eine alternative Ausführungsform eines Pressen-Antriebsmoduls in Prinzipdarstellung,

Figur 4

eine mit den gleichen Pressen-Antriebsmodulen wie die Presse gemäß Figur 1 aufgebaute kleinere Presse in schematisierter Prinzipdarstellung,

Figur 5 und 6

eine Pressenbaureihe mit Pressen unterschiedlicher Größe, die mit gleichen Pressen-Antriebsmodulen bestückt sind, wobei die Ausführungsbeispiele der Figuren 5 und 6 nicht unter den Schutzbereich der Ansprüche fallen,

Figur 7

Leistungsklassen verschiedener Serien von Pressen-Antriebsmodulen,

Figur 8

ein Pressen-Antriebsmodul in Prinzipdarstellung,

Figur 9

ein Pressen-Antriebsmodul in Prinzipdarstellung, das alternativ zu der erfindungsgemäßen Lösung keine parallel sondern seriell angeordnete Antriebseinrichtungen aufweist und

Figur 10

eine Maximalkraft/Weg-Kennlinie eines Pressen-Antriebsmoduls.

In the drawings, embodiments of the invention are illustrated. Show it:

FIG. 1

a press with modular press drive in schematic schematic representation,

FIG. 2

a press drive module for the press FIG. 1 in a schematic representation,

FIG. 3

an alternative embodiment of a press drive module in a schematic representation,

FIG. 4

one with the same press drive modules as the press according to FIG. 1 built smaller press in a schematic diagram,

FIGS. 5 and 6

a press series with presses of different sizes, which are equipped with the same press drive modules, the embodiments of the FIGS. 5 and 6 do not fall within the scope of the claims,

FIG. 7

Performance classes of different series of press drive modules,

FIG. 8

a press drive module in schematic representation,

FIG. 9

a press drive module in a schematic representation, the alternative to the solution according to the invention has no parallel but serially arranged drive means and

FIG. 10

a maximum force / displacement characteristic of a press drive module.

In FIG. 1 a press 1 is schematically illustrated. The press 1 is preferably a large press, for example a body press. It can form a press stage of a press line or a transfer press. The press 1 has a press frame 2, to which at least one table 3 belongs. Furthermore, the press 1 according to the embodiment according to FIG. 1 Press stand 4, 5 and the stand 4, 5 connecting head piece 6. Between the press stands 4, 5, a plunger 7 is linear, slidably mounted in the present embodiment, vertically. Between the plunger 7 and the table 3, a subdivision tool 8 and an upper tool 9 subdivided pressing tool 10 is arranged.

In order to move the plunger 7 specifically and thus to open and close the pressing tool 10, between the plunger 7 and the head piece 6 with each other the same, unified press drive modules 11, 12, 13 are arranged. The press drive modules can generate at least one pushing or pushing force to move the plunger 7 downwards. If necessary, they can also be designed so that they can lift the plunger 7. In a particular in very large presses, the plunger 7 have a considerable weight, engages the plunger 7 in addition to a FIG. 1 not illustrated weight balancing device, for example in the form of a pressurized pneumatic cylinder, which serves to compensate for the plunger weight.

The press drive modules 11 to 13 are connected to a control device 14, which controls the operation of the press drive modules 11 to 13. For example, the press drive modules 11 to 13 via the corresponding lines 15, 16, 17 are applied to effect the adjusting movement with energy, for example in the form of electrical energy or a pressurized fluid or both. Alternatively, it is possible to transmit both control pulses and power via the lines 15 to 17, wherein the press drive modules 11 to 13 then follow the control pulses. If required, the lines 15, 16, 17 can also be designed such that information supplied by the press drive modules 11 to 13, for example, position information, is reported back to the control device 14. In this sense, the lines 15, 16, 17 are to be understood as cables, as fluid lines, cable bundles, fluid line bundles or bundles of lines, which contain both electrical lines and fluid lines.

If necessary, the press 1 can be provided with one or more position sensors 18, 19 for detecting the position of the plunger, which are also connected to the control device 14.

FIG. 2 illustrates the press drive module 11, which is representative of the other two press drive modules 12, 13. It can be provided between the head piece 6 and the plunger 7 to increase the pressing force of the press 1 more equal trained press drive modules.

The press drive module 11 is separately in FIG. 2 schematically illustrated in an exemplary embodiment. It contains two drive devices 20, 21 which generate the forces acting between drives 22, 23 and the drives 22, 23 move against each other. The power take-offs 22, 23 have, for example, the shape of mechanical connecting means, such as flanges, couplings or the like, and are as FIG. 1 illustrated, respectively connected to the head piece 6 and the plunger 7. In other words, the outputs 22, 23 are connection means for transmitting power between the press drive module 11 and the head piece 6 or the plunger 7 in the direction of movement of the plunger 7 and thus in the direction of action of the press drive module 11.

The two drive means 20, 21 of the press drive module 11 have different force / displacement characteristics and movement characteristics I and II, such as FIG. 10 shows. The first drive device 20 whose characteristic curve forms the characteristic load I is designed as a servo drive device. It has a servo motor 25 held on a frame 24, which drives an eccentric 27 or a corresponding crank drive via a gear drive 26. The crank is rotatable about an axis 28 and mounted in the frame 24. The frame 24 is directly connected to the output 22. The eccentric 27 drives via a connecting rod 29 an intermediate plunger 30, which is guided in the frame 24.

The intermediate plunger 30 is connected to the second drive means 21, whose characteristic curve forms the characteristic branch II and which is in the form of a hydraulic cylinder 31, in which a displaceably mounted piston 32 is arranged. The hydraulic cylinder 31 is directly connected to the second output 23. In it, two working chambers 33, 34 are limited, which are controlled acted upon by hydraulic fluid.

In order to control the drive devices 20, 21, the servomotor 25 is provided with a control line 35, which forms part of the line 15. In addition, it may have a position sensor which sends position signals via a sensor line. In addition, the line 15 may include a hydraulic line 37, which serves to control the working chamber 34. Another hydraulic line for driving the hydraulic chamber 33 is not illustrated, but may also be present. To control the drive device 21 serve, for example, a hydraulic valve 38, a pressure source, which is not illustrated, and a pressure accumulator 39, the in FIG. 2 is shown only schematically.

The press drive module 11 and the press 1 described so far operate as follows:

The press drive modules 11, 12, 13 are controlled synchronously by the control device 14 in order to generate an up and down movement of the plunger 7. The traversed by the plunger 7 path / time curve is similar, for example, a sine curve with much flattened lower shaft. While the upper part of this curve means a low-force opening and closing of the pressing tool 10, the lower part of the displacement / time curve refers to a small lifting portion above the bottom dead center of the plunger 7, where the actual material deformation takes place. For example, if the stroke is 500 mm, the force to be transmitted to the plunger 7 in the upper 400 mm is usually relatively small, while it may be greater in the lower 100 mm. Depending on the application, the Be shifted ratios to larger or smaller parts of the way.

The press drive module 11 uses the drive device 20 to quickly travel through sections of the total stroke, but with relatively small forces. The yielded by the drive device 20 stroke of the intermediate plunger 30 is less than the desired total stroke. In the numerical example described above, with the first drive means 20, for example, the upper 400 mm travel path of the ram travel can be traversed. In this case, the transmission ratio between the servomotor 25 and the intermediate plunger 30 is constantly changing. The reduction is approaching infinity when approaching the upper and lower dead center. This means that the ratio between the distance between the intermediate plunger 30 and the angle of rotation of the servomotor 25 is 0 for a short time. These positions, which may also be referred to as an extended position, represent support positions of the upper drive device 20. In these positions, the upper drive device 20 can support very large forces.

If the upper drive device 20 reaches its extended position when the plunger 7 approaches its bottom dead center, the second drive device 21 is activated. Hydraulic fluid now flows into the working chamber 34 to carry out the last 100 mm working stroke. The path / time profile of the plunger movement is adjustable by influencing the mass flow of the inflowing hydraulic fluid within wide limits. The force that can be generated between the drives 22, 23 in this case corresponds to the force of the second drive device 21. In principle, this can be substantially greater than The otherwise applicable from the first drive means 20 force, because this is in stretched or neutral position, so that the servo motor 25 remains largely free of force.

To control the position of the second drive means 21, a position sensor 40 may be provided which monitors the position of the piston 32. The position sensor 40 may be connected to the control device 14 via a sensor line 41 belonging to the line 15.

The drive devices 20, 21 can, as described, be activated one after another in time. It is also possible to activate them at least slightly overlapping in time, i. to begin with the operation of the drive means 21 when the drive means 20 approaches its bottom dead center. This ensures a smooth, jerk-free transition of the drive movements. In addition, the drive device 21 can act in addition, when the speed of the intermediate plunger 30 approaches the value zero when approaching the lower stretched position.

The proposed press drive module has the advantage that on the one hand can be used with relatively small servo motors and on the other hand, only relatively small hydraulic fluid flows are required to operate the second drive means 21.

The two drive devices 20, 21 use in the presented embodiment different drive concepts that even emanate from different types of energy (electric energy and hydraulic energy). However, it is also possible, two drive means 20-1, 21-1 to each other combine, use the same drive power as FIG. 2 illustrated. The press drive module 11-1 shown there is based on two servomotors 25a, 25b, both of which actuate a respective screw jack. The screw jack of the drive device 20-1 acts directly on the lower output 23-1 while its servomotor 25a is directly connected to the upper output 22-1. By contrast, the servomotor 25b and its screw jack gear act via a toggle mechanism 42, which is arranged between the upper output 22-1 and the lower output 23-1. In terms of effect, both drive devices 20-1, 21-1 are thus arranged in parallel. Nevertheless, the two drive devices 20-1, 21-1 complement each other due to their different force / displacement characteristics. For example, the drive device 20-1 increases the usable lift to values that can not be achieved with the drive device 21-1 alone. The difference between the characteristics is here effected by the fact that the drive device 20-1 acts directly and the drive device 21-1 indirectly via a toggle mechanism.

As FIG. 4 illustrates, with the press drive modules 11, 12 build different sized presses. FIG. 4 FIG. 1 illustrates a press 1 ', the plunger 7 of which is driven by only two press drive modules 11, 12. These are with the drive modules 11, 12 of the press 1 according to FIG. 1 identical. The above description thus applies accordingly. Will the electro-hydraulic press drive modules 11, 12 according to FIG. 2 used, the drive means 21 are buffered via the pressure accumulator 39, so that a corresponding network load is made uniform. The servomotors 25 may also consist of a buffer 43 be operated for example in the form of a motor generator set, a capacitor bank or other suitable memory. The control device 14 is also connected to a network 44, from which it draws relatively even energy, for example, for recharging the buffer 43.

The press drive modules 11, 12 of the embodiments described above are constructed as separate units with or without their own housing, which can be installed as prefabricated units in presses. The FIGS. 5 and 6 illustrate a modified embodiment, in which combined and unified press drive modules 11, 12 are used, which are partially integrated in the presses 1a, 1b. For the general description of the presses 1a, 1b, reference is made to the above description on the basis of the introduced reference numbers.

Similar to the drive module 11 according to FIG. 2 are the drive modules 11, 12 belonging to a common series presses 1a, 1b of FIGS. 5 and 6 combined designed as a servomotor-driven eccentric or crank mechanism and hydraulic cylinder. However, the drive means 20, 21 are not combined into a separate unit, but part of the head piece 6 and the plunger 7. However, the module concept described above is taken over insofar as the drive means 20, 21 are formed identical to each other in all presses of the illustrated series. The comparatively smaller press 1a contains only one press drive module 11 while the press 1b contains two or more drive modules 11, 12 and so on. The illustrated press series thus differs in terms of their drives only by the number the press drive modules used, but not by their structure.

voneinander unterscheiden. Durch Kombination verschiedener Pressen-Antriebsmodule unterschiedlicher Leistungsklassen jedoch gleichen Hubs lassen sich somit nicht nur Pressenleistungen im Rahmen ganzzahliger Vielfacher der Leistungen einzelner Antriebsmodule sondern auch Zwischenstufen erreichen.In a modification of this embodiment, it is possible to provide press drive modules of different power or power classes or Hubklassen. An example is in FIG. 7 illustrated. It shows five different press drive module types whose performances are, for example, exponential. You can, for example, by the factor $\sqrt{2}$

differ from each other. By combining different press drive modules of different performance classes, but with the same hubs, it is thus possible not only to achieve press outputs in the context of integer multiples of the powers of individual drive modules but also intermediate stages.

FIG. 8 illustrates in the most schematic way a further embodiment of a press drive module 11-2 with two drive means 20-2, 21-2 with servomotors 25b, 25c. These work with different ratios via gear drives 45, 46 on a common threaded spindle 47 which drives a spindle nut 48 linearly reciprocating. The servo motor 25b is capable of transmitting relatively large torques to the lead screw 47 while the servo motor 25c transmits smaller moments but slows down at a given spindle speed. Thus, the servo motor 25c can generate very fast adjusting movements while the servomotor 25b can generate very high pressing forces. At high speed, ie driving the servo motor 25c at full power, the servomotor 25b runs at high speeds, where he himself could no longer deliver corresponding torque. Thus, will the scope of application of servo motor drives for press rams has been expanded. The solution is simple and requires no couplings per se. However, if required, between the gear drive 45 and the servo motor 25b, a switchable clutch or a freewheel can be arranged. It is also possible to provide two counter-rotating freewheels, which can be blocked as required.

Another variant of a press drive module 11-3 verschaulicht FIG. 9 , This is based on two hydraulic drive devices, 20-3, 21-3, which are arranged in series between the drives 22-3, 23-3. The hydraulic drive device 20-3 is designed for long strokes with relatively little force. The hydraulic drive device 21-3 is designed for short strokes with high force. Between two drive devices 20-3, 21-3, a braking device 49 is provided, with which the comparatively weaker drive device 20-3 is firmly braked. In this way, the higher force emanating from the drive device 21-3 upon activation can be supported and thus transmitted to the output 22-3. The illustrated press drive module 11-3 thus consumes much less hydraulic fluid at high speed than a correspondingly large hydraulic cylinder and is able to generate the required high driving forces on a part of the movement curve of the plunger.

According to the invention press drive modules are proposed, which allow a unified press design. The presses of a series are equipped with always the same press drive modules, wherein the pressing force of the presses only by adjusting the number of press drive modules is varied. The press drive modules each contain two drive devices which interact in parallel and have different characteristics. In particular, they have different maximum travel speeds and different maximum forces. They can also be designed differently in terms of their positioning and path resolution. This concept allows not only a standardization of presses of different performance classes within a series but also the largely free determination of path / time curves of the plunger and thus ultimately a freer design of workpieces, especially body parts.

Claims (18)

1. Press drive module for a press slide (7) for generating a drive movement and a pressing force between a first output (22) to be connected to a press frame (2) and a second output (23) connected to the press slide (7),
   with a first drive device (20), which is connected to at least one of the at least two outputs (22, 23) and has a first force-path characteristic,
   with at least one second drive device (21), which is connected at least to the other of the at least two outputs (22, 23) and has a second force-path characteristic,
   wherein the force-path characteristics of the at least two drive devices (20, 21) are defined differently,
   wherein the at least two drive devices (20, 21) are arranged to act in parallel, characterised in that
   the press drive module (11) forms a separate structural unit from the press.
2. Press drive module according to claim 1, characterised in that at least one of the drive devices (20, 21) contains a gear (27, 29) with variable transmission ratio.
3. Press drive module according to claim 2, characterised in that the gear (27, 29, 42) has a support point, in which the ratio of motion on the output side to motion on the input side is zero.
4. Press drive module according to claim 1, characterised in that at least one of the drive devices (20,21) has a servomotor (25) as drive source.
5. Press drive module according to claim 1, characterised in that the at least two drive devices (20, 21) are activated temporally one after the other.
6. Press drive module according to claim 1, characterised in that the at least two drive devices (20, 21) are activated simultaneously.
7. Press drive module according to claim 1, characterised in that the press drive module (11) has its own base frame (24).
8. Press drive module according to claim 1, characterised in that the press drive module (11) has a housing, in which the at least two drive devices (20, 21) are accommodated.
9. Press drive module according to claim 1, characterised in that the drive devices (20, 21) have an associated energy storage means (39, 43).
10. Press drive module according to claim 9, characterised in that the energy storage means is a mechanical energy storage means.
11. Press drive module according to claim 9, characterised in that the energy storage means is a pneumatic/hydraulic energy storage means (39).
12. Press drive module according to claim 9, characterised in that the energy storage means is an electrical energy storage means (43).
13. Press drive module according to claim 1, characterised in that at least one of the drive devices (20, 21) is connected to one of the outputs by means of a coupling device.
14. Method for providing a press array comprising multiple presses (1a, 1b) of different pressing force with respective press drive modules (11, 12, 13) according to one of the preceding claims for their press slides (7) for generating a drive movement and a pressing force between a first output (22) to be connected to a press frame (2) and a second output (23) connected to the press slide (7),
    wherein the press drive modules respectively have:

    a a first drive device (20), which is connected to at least one of the outputs (22) and has a first force-path characteristic, and

    b. at least one second drive device (21), which is connected at least to the other of the at least two outputs (23) and has a second force-path characteristic,

    wherein the force-path characteristics of the at least two drive devices (20, 21) arc defined differently,
    wherein the at least two drive devices (20, 21) are arranged to act in parallel,
    and
    wherein uniform drive modules (11, 12) are used in different numbers within the press array for presses (1a, 1b) of different pressing force.
15. Method according to claim 14, characterised in that drive modules (11, 12) in at least two different power classes are provided for the press array, wherein the drive modules (11, 12) are uniform within each power class.
16. Method according to claim 15, characterised in that the drive modules (11, 12) of the different power classes have the same maximum strokes.
17. Method according to claim 15, characterised in that the drive modules (11, 12) in at least three power classes are provided and that the power classes are graduated exponentially.
18. Method according to claim 15, characterised in that the power classes are determined by the maximum force that can be produced by the drive modules (11, 12).

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