Realignment device and method for plate-shaped workpieces in a processing machine

Abstract

The present invention relates to a readjustment device and method for a machine tool (1) for machining a plate-like workpiece (10), preferably sheet metal, comprising an upper pressure application device (234) including at least pressure plungers (241) oriented at a distance from one another, a lower support device (235) having at least counter-bearings (260) arranged at a distance from one another, and oriented in an operating position (232) so as to clamp against the pressure plungers (241) of the upper pressure application device (234) and fix the plate-like workpiece (10). and a lower support device (235) attached to the upper pressure application device (234), and at least one drive device (243) by which a pressure plunger (241) of the upper pressure application device (234) can be moved from a rest position (231) to an actuated position (232), wherein the at least two pressure plungers (241) of the upper pressure application device (234) are coupled to each other and controlled to be movable or pivotable together between the rest position (231) and the actuated position (232).

Description

[Technical field]

[0001] The present invention relates to a readjusting device for a plate-shaped workpiece on a machine tool for machining the plate-shaped workpiece and also to a method for readjusting a plate-shaped workpiece for machining on a machine tool. [Background technology]

[0002] EP 1 339 636 A1 discloses a machine tool for machining plate-shaped workpieces by punching. The machine tool comprises an upper tool and a lower tool for machining a plate-shaped workpiece located on a worktable. For the purpose of machining, the plate-shaped workpiece is held by a feeding device and moved relative to the punching tool by means of a gripper. In order to obtain a complete machining of the plate-shaped workpiece, the plate-shaped workpiece needs to be readjusted, which means that a gripping of the gripping elements of the feeding device on the plate-shaped workpiece along the axis of the working plane takes place. During the readjustment, the plate-shaped workpiece needs to be fixed relative to the worktable. For this purpose, two hydraulically controllable cylinders are provided, which are arranged at a distance from each other and relative to the punching tool. Provided at the extensible end of the piston rod is a pressure piece which is fed to a counter-bearing positioned in the worktable in order to obtain a clamping of the plate-shaped workpiece.

[0003] Two lift cylinders which can be controlled independently of each other and of a counter bearing located opposite the pressure piece form the readjustment device.

[0004] This readjustment device has the disadvantage that it cannot generate high forces for the fixing of the plate-like material. In addition, these cylinders require a large installation space, in particular a large construction height. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Chinese Patent No. 104550536B Specification Summary of the Invention [Problem to be solved by the invention]

[0006] The invention is based on the object of proposing a readjustment device for a machine tool for machining plate-shaped workpieces, which allows a high holding force for the fastening of the plate-shaped workpiece in order to increase the process safety.Furthermore, the invention is also based on the object of proposing a method for readjusting a plate-shaped workpiece for machining on a machine tool, whereby the position of the plate-shaped workpiece is maintained by a high holding force in order to increase the process safety. [Means for solving the problem]

[0007] This object is realized by a readjusting device for a machine tool for machining plate-shaped workpieces, in which the upper pressure application device comprises at least two pressure plungers arranged at a distance from one another, at least two counter-bearings of the lower support device arranged at a distance from one another can be positioned so as to be located opposite the pressure plungers, and the readjusting device comprises a drive device, by means of which the pressure plungers of the pressure application device can be transferred from a rest position to an operating position, the at least two pressure plungers of the upper pressure application device being coupled to one another and movable or swivellable together between the rest position and the operating position. The coupling of at least two pressure plungers, which are transferred together from the rest position to the operating position, in particular simultaneously or successively, allows these pressure plungers to act on the plate-shaped workpiece with the same pressure or pressing force, respectively, in order to fix the plate-shaped workpiece by clamping against the respective counter-bearings located opposite the pressure piece. This further enables the release of the gripper of the feeding device and the prevention of a rotational movement of the plate-shaped workpiece about the Z axis on the worktable during mounting, i.e. in the XY plane. In addition, due to the movable arrangement from the rest position to the working position, the combination of at least two pressure plungers of this upper pressure application device has the advantage that a compact constructive height can be obtained, so that further components of the machine tool, such as a removal device including a gripper device, can be inserted and positioned between the upper tool and the plate-shaped workpiece, for example to remove the generated workpiece part from the plate-shaped workpiece.

[0008] According to an advantageous configuration of the readjusting device, the at least two pressure pieces can be moved synchronously by a coupling or connecting mechanism, which allows a simplified control of the two pressure plungers, which can be moved together and simultaneously for the application of a holding force to the plate-shaped workpiece.

[0009] Preferably, at least two pressure pieces of the upper pressure applicator can be controlled by a coupling mechanism, the pressure pieces being arranged on the output side and the at least one drive device being arranged on the input side, such that the at least one drive device can control the movement or pivoting movement of the pressure pieces in a defined amount between the rest position and the working position.

[0010] Furthermore, preferably, in the working position the pressure plunger is oriented facing the plate-shaped workpiece, in particular perpendicular to the plate-shaped workpiece, and in the rest position is moved upwards or pivoted laterally relative to the plate-shaped workpiece, as a result of which, outside the reconditioning process, when the reconditioning device is not in use, accessibility to the plate-shaped workpiece and increased free space between the upper tool and the plate-shaped workpiece are provided.

[0011] Furthermore, the lower support device is preferably configured to be separated or decoupled from the upper pressure application device, which allows for a simplified structural design and a simplified installation of the readjustment device in the machine tool.

[0012] Advantageously, the pressure plunger of the upper pressure application device comprises a cylindrical housing in which a pressure pin is arranged mounted by a spring, the pressure pin being guided so that it can sink into the housing counter against the flexible element when a clamping force is applied to the plate-like workpiece. As a result, firstly, it is possible to apply a sufficiently defined pressing force and, secondly, it is possible to compensate for tolerances.

[0013] Preferably, a force storage element, in particular a preload spring assembly, for applying a force, in particular a spring force, via the pressure pin is provided in the housing of the pressure plunger. Advantageously, a preload disc spring assembly is provided, so that in the case of a forward movement a defined force increase can be obtained.

[0014] The upper pressure applicator of the readjustment device preferably has a body or a holding element in which two parallel oriented pivot axes are provided at a distance for the pivotable arrangement of the pressure plunger, which can be used to move the pressure plunger from a retracted rest position to an extended working position. This pivotable arrangement of the pressure plunger on the body of the pressure applicator makes it possible to obtain a low or compact constructional height in the rest position. In addition, the transition of the pressure plunger to the extended working position makes it possible for the longitudinal axis of the pressure plunger to lie, for example, in the Z-axis, thus obtaining a large clamping force in the case of a forward movement of the upper tool for clamping the plate-shaped workpiece.

[0015] On the upper pressure applicator, the pivot axes are preferably provided spaced apart from one another on the body or on the holding element, so that the pressure plungers are located one behind the other in the retracted rest position, in particular located side by side, and are preferably oriented in a horizontally oriented row. As a result, the upper pressure applicator has a small height and a small width.

[0016] Furthermore, in the extended working position, the pressure plunger preferably abuts against an end stop that defines the extent of its pivotal movement, thereby allowing for direct force transmission from the upper tool through the body and the end stop to the pressure plunger in the event of a stroke movement of the upper tool.

[0017] Advantageously, the drive is rotatably mounted on the body of the upper pressure applicator and controls a linkage for retracting and extending the pressure plunger between the rest position and the working position, the upper pressure applicator being consequently in the form of a mounting assembly.

[0018] The drive preferably comprises a reciprocating piston having an extendable piston rod with a linkage controlled. The reciprocating piston may be hydraulically, pneumatically or electromagnetically controllable. Alternatively, the drive may be in the form of a gear mechanism, a cam control system or a linear drive mechanism.

[0019] Advantageously, a toggle lever mechanism is provided between the drive device and a slide member or lever arm of the coupling mechanism which engages the pressure plunger and the drive device, as a result of which a force assist can be achieved, especially when transferring the pressure plunger to the rest position.

[0020] The upper pressure applicator of the readjustment device preferably has a connection interface located on the body or holding element opposite the pressure plunger, said connection interface being usable for releasably fixing the pressure applicator to the upper stroke drive or the upper tool of the machine tool, thereby allowing a simple and quick installation of such an upper pressure applicator.

[0021] Furthermore, preferably, a readjustment position can be set between the housing and the pressure pin of the pressure plunger. This can be realized, for example, by a distance compensation element or the like. By way of example, the pressure pin can be of two-part form so that the distance compensation element can be configured to be located therebetween. Furthermore, as an alternative, the readjustment position of the pressure plunger arranged in the working position can be set between the interface of the upper stroke drive and the upper pressure applicator. Preferably, a distance compensation element, preferably having a predetermined change in thickness, can also be arranged to be located therebetween.

[0022] Furthermore, in order to accommodate the at least two counter-bearings, the lower support device preferably has a support frame which can be fixed to the lower stroke drive or to the lower tool, said support frame preferably being of rigid form in order to avoid deflections, in particular in the plane of the worktable.

[0023] The counter-bearing of the lower support device may be in the form of a rigid counter-bearing according to the first aspect. Alternatively, a lowerable counter-bearing may be used. As a result of the configuration of the lowerable counter-bearing, scratch-free processing may be possible, especially in the case of softer plate-shaped workpieces.

[0024] The object on which the invention is based is further realized by a method for readjusting a plate-shaped workpiece for machining on a machine tool, in which the readjusting process is carried out by a readjusting device according to one of the above-mentioned embodiments, in order to readjust the plate-shaped workpiece between two machining cycles in which the plate-shaped workpiece is machined with a tool. This method has the advantage that the pressure plunger of the readjusting device moves towards the counter-bearing of the lower support device and is simultaneously located on the plate-shaped workpiece, in order to clamp the plate-shaped workpiece therebetween. As a result, it is possible to take up and maintain a reliable clamping position for gripping the plate-shaped workpiece during its machining and for carrying out the readjusting process by a movement of a feed device moving at least along the X-axis, at least along the X-axis of the worktable.

[0025] Preferably, at the start of a readjustment cycle, the plate-shaped workpiece is held fixed by the readjustment device in a position relative to the worktable, and the gripping position of the feeding device relative to the plate-shaped workpiece is released, and the feeding device is moved by the readjustment movement amount relative to the plate-shaped workpiece, and the plate-shaped workpiece is fixed by the gripper of the feeding device in a gripping position changed by the readjustment movement amount. As a result, complete processing of the plate-shaped material can be realized, especially in the case of long plate-shaped workpieces whose length exceeds the movement amount of the feeding device.

[0026] Furthermore, in a first working step of the realignment process, the upper pressure applicator of the realignment device is preferably moved to an upper end position relative to the machine frame, and the at least two pressure plungers are then transferred from the rest position to the working position, as a result of which a reliable extension or pivoting of the pressure plungers to the working position can be made possible without collision with the plate-shaped workpiece 10.

[0027] In a subsequent working step of the realignment process, the upper pressure applicator is preferably moved towards the plate-shaped workpiece and the plate-shaped workpiece is clamped and held between the upper pressure applicator and the lower support device. The movement of the upper pressure applicator along the Z axis makes it possible to obtain a tilt-free arrangement of the at least two pressure plungers.

[0028] Then, preferably after the plate-shaped workpiece has been clamped and fixed by the readjustment device, the gripper of the feeding device is released and the plate-shaped workpiece is controlled to move away from the gripper of the feeding device along the Y-axis. As a result of this movement away from the gripper, in particular out of the clamping jaws of the gripper, there is a straightness error of the side edge of the plate-shaped workpiece during the execution of the readjustment movement, without affecting the clamping position of the plate-shaped workpiece in the readjustment device. When moving the plate-shaped workpiece away, the end side of the plate-shaped workpiece pointing towards the gripper is preferably not guided completely out of the clamping jaws of the gripper, but rather is only removed from the zero stop located in the clamping jaws.

[0029] After the plate-shaped workpiece has been moved away from the gripper, the feed device is preferably moved along an adjusted travel and the plate-shaped workpiece is then controlled to move towards the gripper of the feed device so that it can again be introduced into the clamping jaws of the gripper in order to provide an enlarged engagement surface for the fixation of the plate-shaped workpiece.

[0030] Specifically, in the case of a first readjustment process, the amount of movement for moving the plate-shaped workpiece away from the gripper is controlled to be greater than the amount of movement for moving the plate-shaped workpiece towards the gripper. This is particularly true in the case of a first readjustment operation, because when the plate-shaped workpiece is first gripped, the end edge of the plate-shaped workpiece that engages in the clamping jaws abuts against the zero stop of the clamping jaws of the gripper with a defined orientation. In the case of further subsequent readjustment processes, the amount of movement for the movements towards and away from the operation is preferably identical.

[0031] Furthermore, preferably, after the readjustment travel has been traversed, the plate-shaped workpiece is clamped and held by the grippers and the upper pressure application device is moved to a rest position and the subsequent processing cycle is started.

[0032] Advantageously, during the readjustment process it is possible to reduce the process parameters for the movement speeds of the feed device and / or the stroke drive, which allows for increased process safety, since in the case of reduced movement speeds and / or accelerations the moment of inertia is reduced.

[0033] Collision monitoring can be performed before and / or during the reconditioning process. In particular, such collision monitoring is performed by a process controller. The result is that the pressure plunger of the upper pressure application device and / or the counter bearing of the lower support device are positioned adjacent to the processed area of ​​the plate-like workpiece. Such processed area in the plate-like workpiece can be a cut-off portion, a raised or recessed portion, or a fold or groove, or the like.

[0034] A further advantageous configuration of the method provides that during the reconditioning process, the clamping of the plate-shaped workpiece by the upper tool and the lower tool is controlled parallel and / or continuously to the reconditioning device. As a result of this further clamping of the plate-shaped workpiece between the upper tool and the lower tool or the scraper on the upper tool and the lower tool, further fixation can be realized. In particular, the pressure plunger and the scraper or the upper tool are arranged in a triangular position relative to each other. As a result, it is possible to clamp and hold the plate-shaped workpiece at three points, and an increased holding moment against the rotation of the plate-shaped workpiece in the XY plane can be obtained.

[0035] The invention and further advantageous embodiments and developments thereof are described and explained in more detail by means of examples shown in the drawings, in which the features which can be seen from the description and the drawings can be used according to the invention individually by themselves or in any combination of multiples. [Brief description of the drawings]

[0036] [Figure 1] FIG. [Diagram 2]FIG. 2 shows a schematic diagram of the basic design of the stroke drive and motor drive mechanism according to FIG. [Diagram 3] 2 shows a schematic plan view of the machine tool according to FIG. 1 with a worktable; [Figure 4] 4 shows a schematic cross-sectional view of a machine tool along line IV-IV in FIG. 1 with a worktable surface assigned to the machine base frame; [Diagram 5] FIG. 2 shows a perspective view of the readjustment device in the rest position. [Figure 6] 6 shows a perspective view of the readjustment device according to FIG. 5 in an operating position. [Figure 7] 1 shows a schematic cross-sectional view of the upper pressure applicator of the reconditioning device in the rest position. [Figure 8] 8 shows a schematic cross-sectional view of the pressure application device according to FIG. 7 in an active position. [Figure 9] 6 shows a perspective view of an alternative embodiment of the upper pressure applicator with respect to FIG. 5 in the rest position. [Figure 10] 10 shows a perspective view of the pressure application device according to FIG. 9 in an active position. [Figure 11] A schematic diagram illustrating the reconditioning process is shown. [Figure 12] A schematic diagram illustrating the reconditioning process is shown. [Figure 13] A schematic diagram illustrating the reconditioning process is shown. [Figure 14] A schematic diagram illustrating the reconditioning process is shown. [Figure 15] A schematic diagram illustrating the reconditioning process is shown. [Figure 16] A schematic diagram illustrating the reconditioning process is shown. [Figure 17] 1 shows a schematic diagram of the upper drive with the readjustment device and the upper tool and scraper in a rest position for a plate-shaped workpiece. [Figure 18] FIG. 2 shows a schematic diagram of an upper stroke drive with a readjustment device in an operative position. [Figure 19] FIG. 18 shows a schematic diagram of the upper stroke drive according to FIG. 17 with the readjusting device and the scraper in the working position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] Figure 1 shows a machine tool 1 in the form of a punch press. This machine tool 1 comprises a load-bearing structure with a closed machine frame 2. Said machine frame comprises two horizontal frame members 3, 4 and two vertical frame members 5 and 6. The machine frame 2 encloses a frame interior space 7, which forms the working area of ​​the machine tool 1 with an upper tool 11 and a lower tool 9.

[0038] The machine tool 1 serves for the machining of a plate-shaped workpiece 10, which for the sake of clarity is not shown in FIG. 1 and which can be arranged for machining in the frame interior space 7. The workpiece 10 for machining is arranged on a workpiece support 8 provided in the frame interior space 7. A lower tool 9, for example in the form of a punching die, is mounted in a cut-out of the workpiece support 8 on the lower horizontal frame member 4 of the machine frame 2. This punching die can be provided with a die opening. In the case of a punching machining operation, an upper tool 11 in the form of a punch is sunk into the die opening of the lower tool in the form of a punching die.

[0039] Instead of a punch and a punching die, the upper tool 11 and the lower tool 9 can also be used as a folding ram and a folding die for shaping the workpiece 10 .

[0040] The upper tool 11 is fixed in the tool receptacle at the lower end of the plunger 12. The plunger 12 is part of a stroke drive 13, by means of which the upper tool 11 can be moved in a stroke direction along a stroke axis 14. The stroke axis 14 extends in the direction of the Z-axis of the coordinate system of the numerical controller 15 shown in FIG. 1 of the machine tool 1. In a direction perpendicular to the stroke axis 14, the stroke drive 13 can be moved along a positioning axis 16 in the direction of the double arrow. The positioning axis 16 extends in the direction of the Y-direction of the coordinate system of the numerical controller 15. The stroke drive 13, which receives the upper tool 11, is moved along the positioning axis 16 by a motor drive 17.

[0041] The movement of the plunger 12 along the stroke axis 14 and the positioning of the stroke drive 13 along the positioning axis 16 are realized by a drive arrangement 17, in particular a motor drive 17 in the form of a spindle drive arrangement, with a drive spindle 18 extending in the direction of the positioning axis 16 and connected in a fixed manner to the machine frame 2. During the movement along the positioning axis 16, the stroke drive 13 is guided on two guide rails 19 of the upper frame member 3, which can be observed in FIG. 1. The remaining guide rail 19 extends parallel to the visible guide rail 19 and is spaced from it in the direction of the X-axis of the coordinate system of the numerical controller 15. A guide shoe 20 of the stroke drive 13 extends on the guide rail 19. The mutual engagement of the guide rail 19 and the guide shoe 20 is such that the connection between the guide rail 19 and the guide shoe 20 can also accommodate loads acting in the vertical direction. The stroke device 13 is therefore suspended on the machine frame 2 by means of guide shoes 20 and guide rails 19. A further part of the stroke drive 13 is a wedge mechanism 21, by means of which the position of the upper tool 11 relative to the lower tool 9 can be set.

[0042] The lower tool 9 is received so as to be movable along a lower positioning axis 25. This lower positioning axis 25 extends in the direction of the Y-axis of the coordinate system of the numerical controller 15. The lower positioning axis 25 is preferably oriented parallel to the upper positioning axis 16. The lower tool 9 can be moved along the positioning axis 25 by a motor drive arrangement 26 directly on the lower positioning axis 16. Alternatively or in addition, the lower tool 9 can also be provided on a stroke drive 27 which can be moved along the lower positioning axis 25 by the motor drive arrangement 26. This drive arrangement 26 is preferably in the form of a spindle drive arrangement. The lower stroke drive 27 can correspond in design to the upper stroke drive 13. Similarly, the motor drive arrangement 26 can also correspond to the motor drive arrangement 17.

[0043] Likewise, the lower stroke drive arrangement 27 is displaceably mounted on a guide rail 19 assigned to the lower horizontal frame member 4. The guide shoe 20 of the stroke drive 27 extends on the guide rail 19 such that the connection between the guide rail 19 on the lower tool 9 and the guide shoe 20 can also accommodate vertically acting loads. The stroke drive 27 is therefore also suspended on the machine frame 2 by the guide shoe 20 and the guide rail 19 and at a distance from the guide rail 19 and the guide shoe 20 of the upper stroke drive 13. The stroke drive 27 may also include a wedge mechanism 21, by means of which the position or height of the lower tool 9 along the Z-axis is settable.

[0044] The numerical controller 15 allows to control both the motor drive mechanism 17 for the movement of the upper tool 11 along the upper positioning axis 16 and the one or more motor drive mechanisms 26 for the movement of the lower tool 9 along the lower positioning axis 25 independently of each other. Thus, the upper and lower tools 11, 9 can be moved synchronously in the direction of the Y-axis of the coordinate system. Similarly, the independent movements of the upper and lower tools 11, 9 can also be controlled in different directions. This independent movements of the upper and lower tools 11, 9 can be controlled simultaneously. The separation of the movements between the upper tool 11 and the lower tool 9 allows to obtain increased flexibility in the processing of the workpiece 10. The upper and lower tools can also be configured in various ways for the processing of the workpiece 10.

[0045] Part of the stroke drive 13 is the wedge mechanism 21, which is shown in FIG. 2. The wedge mechanism 21 comprises two drive wedge mechanism elements 122, 123 and also two output wedge mechanism elements 124, 125. The latter are structurally combined to form a structural unit in the form of an output double wedge 126. The plunger 12 is mounted on the output double wedge 126 so as to be rotatable about the stroke axis 14. A motor rotary drive 128 is accommodated in the output double wedge 126 and advances the plunger 12 about the stroke axis 14 as required. In this case, rotation of the plunger 12 both to the left and to the right is possible according to the double arrow in FIG. 2. The plunger mount 129 is shown diagrammatically. Firstly, the plunger mount 129 allows low-friction rotational movement of the plunger 12 about the stroke axis 14, and secondly, the plunger mount 129 supports the plunger 12 axially and in a corresponding manner relieves loads acting on the plunger 12 in the direction of the stroke axis 14 into the output double wedge 126.

[0046] The output-side double wedge 126 is delimited by a wedge surface 130 and a wedge surface 131 of the output-side mechanism element 125. The wedge surfaces 132, 133 of the drive-side wedge mechanism elements 122, 123 are located opposite the wedge surfaces 130, 131 of the output-side wedge mechanism elements 124, 125. By means of longitudinal guides 134, 135 the drive-side wedge mechanism element 122 and the output-side wedge mechanism element 124 as well as the drive-side wedge mechanism element 123 and the output-side wedge mechanism element 125 are guided so as to be movable relative to one another in the direction of the Y-axis, i.e. in the direction of the positioning axis 16 of the stroke drive 13.

[0047] The drive side wedge mechanism element 122 has a motor drive unit 138 and the drive side wedge mechanism element 123 has a motor drive unit 139. Both drive units 138, 139 together form the spindle drive arrangement 17.

[0048] Common to the motor drive units 138, 139 is the drive spindle 18, which in FIG. 1 is shown in the form of a drive mounted on the machine frame 2 and consequently located on the side of the load-bearing structure.

[0049] With respect to the motor drive units 138, 139, the drive wedge mechanism elements 122, 123 are operated in such a way that they move towards each other, for example along the positioning axis 16, resulting in a relative movement between the drive wedge mechanism elements 122, 123 for one part and the output wedge mechanism elements 124, 125 for the other part. As a result of this relative movement, the output double wedge 126 and the plunger 12 mounted thereon move downwards along the stroke axis 14. For example, the punch 11 mounted on the plunger 12 performs a working stroke and, in so doing, processes the mounted workpiece 10 on the worktable 28, 29 or on the workpiece support 8. And, as a result of the movement of the drive wedge elements 122, 123 in the opposite direction, the plunger 12 rises and moves upwards along the stroke axis 14.

[0050] The above-mentioned stroke drive 13 according to FIG. 2 preferably has the same design as the lower stroke drive 27 and accommodates the lower tool 9 .

[0051] FIG. 3 shows a schematic view of the machine tool 1 according to FIG. 1. The individual workpiece tables 28, 29 extend laterally on the machine frame 2 of the machine tool 1. The workpiece table 28 can, for example, be assigned to a loading station (not shown in further detail), whereby the unmachined workpiece 10 is placed on the workpiece table surface 28. Provided adjacent to the workpiece table surface 28, 29 is a feed device 22 which includes a number of grippers 23 for gripping the workpiece 10 placed on the workpiece table 28. The workpiece 10 is guided in the X-direction through the machine frame 2 by the feed device 22. Preferably, the feed device 22 can also be controlled to be movable in the Y-direction. This allows for a free movement of the workpiece 10 in the XY-plane to be provided. Depending on the working task, the workpiece 10 can be movable by the feed device 22 both in the X-direction and in the anti-X-direction. This movement of the workpiece 10 can be adapted to the movements of the upper tool 11 and the lower tool 9 in the Y direction and counter Y direction for each individual machining task.

[0052] A further workpiece table 29 is provided on the machine frame 2 such that it is located opposite the workpiece table 28. This can be assigned, for example, to an unloading station. Alternatively, the loading and unloading of the unmachined workpiece 10 and the machined workpiece 10 with the workpiece 81 can be assigned to the same workpiece table 28, 29.

[0053] The machine tool 1 may further comprise a laser processing device 201, in particular a laser cutting machine, which is only diagrammatically shown in the plan view of FIG. 3. This laser processing device 201 may, for example, be in the form of a CO2 laser cutting machine. The laser processing device 201 comprises a laser source 202, which generates a laser beam 203, which is guided by a diagrammatically shown beam guide 204 to and focused in a laser processing head, in particular a laser cutting head 206. The laser beam 203 is then directed perpendicularly to the surface of the workpiece 10 by a cutting nozzle in order to process the workpiece 10. The laser beam 203 acts on the workpiece 10 at a processing location, in particular a cutting location, preferably together with a process gas beam. The cutting point, at which the laser beam 203 is incident on the workpiece 10, is adjacent to the processing points of the upper tool 11 and the lower tool 9.

[0054] The laser cutting head 206 can be moved at least in the Y direction, preferably in the Y and Z directions, by a linear drive mechanism 207 having a linear axis system. This linear axis system, which accommodates the laser cutting head 206, can be assigned to the machine frame 2, fixed thereto or integrated therein. A beam-passing opening 210 in the work table 28 is provided below the working space of the laser cutting head 206. Preferably, a beam collector for the laser beam 21 can be provided below the beam-passing opening 210. The beam-passing opening 210 and possibly the beam collector can also be in the form of a structural unit.

[0055] Alternatively, the laser processing apparatus 201 may have a solid-state laser as the laser source 202, the radiation of which is guided to the laser cutting head 206 using a fiber optic cable.

[0056] Figure 4 shows a schematic cross-section according to line VI-VI in figure 1. In this view of the machine tool 1, the vertical frame members 5 and 6 as well as the upper horizontal frame member 3 are omitted. This view shows that the workpiece stage 28, 29 extends directly onto the workpiece support 8 which at least partially surrounds the lower tool 9. In the free space created therebetween, the lower tool 9 can be moved in the Y-direction and counter-Y-direction along the lower positioning axis 25. Furthermore, if this machine tool 1 is equipped with a laser processing device 21, a beam-passing opening 210 in the workpiece stage 28 is shown.

[0057] Resting, for example, on the workpiece table 28 is the machined workpiece 10, in which, for example with the exception of the remaining connection 82, a workpiece part 81 is cut off by a cutting gap 83, for example by a punching or laser beam machining operation. Due to this remaining connection, the workpiece part 81 is held in the workpiece 10 or in the remaining scrap skeleton. In order to cut off the workpiece part 81 from the workpiece 10, the workpiece 10 is positioned by the feed device 22 against the upper and lower tools 11, 9 for a separation and ejection step. In this case, the remaining connection 82 is cut off by a punching stroke of the upper tool 11 against the lower tool 9. The workpiece part 81 can be ejected downwards, for example by a partial drop of the workpiece support 8. Alternatively, in the case of a larger workpiece part 81, the cut off workpiece part 81 can be transferred again back to the workpiece table 28 or the workpiece table 29 in order to remove the workpiece part 81 and the scrap skeleton. The small workpiece portion 81 can optionally also be ejected through an opening in the lower tool 9 .

[0058] Fig. 5 shows the realignment device 230 in a rest position 231. Fig. 6 shows the realignment device 230 according to Fig. 5 in an operating position 232. The realignment device 230 comprises an upper pressure applicator 234 and a lower support device 235. The upper pressure applicator 234 is provided on the upper stroke drive 13. The lower support device 235 is provided on the lower stroke drive 27. The pressure applicator 234 and the support device 235 are preferably oriented adjacent to the upper tool 11 and the lower tool 9, respectively.

[0059] 7 and 8 show cross-sectional views of the upper pressure applicator 234 in the rest position 231 and in the working position 232. The upper pressure applicator comprises a mounting interface 240 for releasable arrangement on the stroke drive 13. Provided on the opposite side of said mounting interface are, by way of example, two pressure plungers 241 which are transferable from the rest position 231 to the working position 232 by means of a coupling mechanism 242. In the working position 232, the pressure plungers 241 face the plate-shaped material 10. In particular, they are oriented perpendicularly to the plane of the plate-shaped workpiece 10 in the working position 232. To control the movement of the pressure plungers 241, a drive device 243 is provided. This drive device 243 is preferably configured to be rotatable about a bearing 244. As a result, the drive device 243 can perform a corresponding pivoting movement during the actuation of the coupling mechanism 242. In the rest position 231 of the pressure application device 234, the pressure plungers 241 are preferably arranged one behind the other. In particular, the drives 243 are provided in the same plane in the rest position. The drives 243 are, for example, in the form of reciprocating pistons. The linkage 242 is actuated by a piston rod 245. The linkage 242 may be formed of a number of lever arms 246, 247 for controlling the pivoting movement of the pressure plungers 241 about fixedly positioned axes 248. These fixedly positioned axes 248 are provided on a body or holding element 249, which is fixedly connected to the interface 240 and further preferably houses a rotation axis for the bearings 244.

[0060] The drive 243 is actuated to move the pressure plunger 241 from the rest position 231 to the working position 232. By way of example, the piston rod 245 retracts into the piston. The lever arms 246, 247 are controlled such that the pressure plunger 241 executes a pivoting movement through 90°. The end position of the pressure plunger 241 in the working position 232 is realized by a stop 251, which is preferably settable.

[0061] The linkage mechanism 242 may be configured in the manner of a toggle lever principle or may include such a toggle lever principle, so that during the pivotal movement of the pressure plunger 241 from the operating position 232 to the rest position 231, an increased force may be applied to transition the pressure plunger 241 to a horizontal position.

[0062] The pressure plunger 241 consists of a cylindrical housing 254 in which a pressure pin 255 is resiliently mounted. Preferably, a Belleville spring assembly 256 is provided between the housing 254 and the pressure pin 255 so that a degree of flexibility can be applied on one part and sufficient contact pressure on the plate-like workpiece 10 can be applied by the pressure plunger 241 on the other part.

[0063] The lower support device 235 comprises, for example, two counter-bearings 260. The number of counter-bearings 260 is adapted to the number of pressure plungers 241. The counter-bearings 260 are oriented relative to the longitudinal axis of the pressure plungers 241 in the working position 232.

[0064] According to a first embodiment, the counter bearing 260 is provided fixed on the base frame, which may be fixed relative to the lower stroke drive 27. Alternatively, the counter bearing 260 may also be in height adjustable and / or flexible form.

[0065] Fig. 9 shows a perspective view of an alternative embodiment of the upper pressure applicator 234 in the rest position 231. Fig. 10 shows an alternative embodiment of the pressure applicator 234 according to Fig. 9 in the working position 232.

[0066] This embodiment includes an alternative configuration of the linkage 242. In this embodiment, the linkage 242 is in the form of a scissor-type configuration. The lever arms 246, 247 can be changed from a flat, folded-together configuration according to Fig. 9 to an extended configuration according to Fig. 10. A type of parallelogram linkage 265 can be provided parallel to the lever arms 246, 247, so that, for example, two pressure plungers 241 arranged on the receiving element 266 can remain oriented in a horizontal manner during the retraction and extension movements of the linkage 242.

[0067] In this embodiment according to Figures 9 and 10, a pressure plunger 241 according to the embodiment of Figures 7 and 8 can be used. Alternatively, it is also possible to provide only a pressure pin 255 which is height adjustable but is provided fixedly on the receiving element 266.

[0068] In this embodiment, to control the movement between the rest position 231 and the actuated position 232, for example to actuate the scissor-type arrangement, two mutually opposed drives 243 are provided acting on the scissor-type arrangement from each side.

[0069] In this alternative embodiment of the pressure application device 234 according to FIGS. 9 and 10, the support device 235 may correspond to the embodiment described above with reference to FIGS.

[0070] 11 to 16 show diagrammatically the individual work steps of a reconditioning process, which is carried out in the machine tool 1 by the reconditioning device 230 according to one of the embodiments described above.

[0071] 11 shows diagrammatically the initial position for the realignment process. The start of the realignment process is required when the displacement of the feed device 22 in the X-direction or anti-X-direction is smaller than the length of the plate-shaped workpiece to be processed, said length extending in the X-direction.

[0072] When the plate-shaped workpiece 10 is first clamped or clamped by the gripper 23, the edge of the plate-shaped workpiece 10 pointing into or facing the gripper 23 is positioned to abut against a zero stop of the gripper 23. This zero stop also serves to orient the plate-shaped workpiece 10 when it is first gripped. The reconditioning process starts after one or more processing steps by the upper and lower tools 11, 9 have been introduced into the plate-shaped workpiece 10. In the rest position 231 according to FIG. 5, the reconditioning device 230, which is shown diagrammatically according to FIG. 11, is controlled and transferred to an operating position 232. This is shown diagrammatically in FIG. 12. In particular, the operating position 232 of the reconditioning device 230 is shown in FIG. 6.

[0073] As a result of the arrangement of the readjusting device 230 in the working position 232, the plate-shaped workpiece 10 is held in a fixed position between the pressure plunger 241 and the opposite counter bearing 260. The gripper 23 is still closed at this point. In addition, the upper tool 11 or a scraper assigned to the upper tool 11 and the lower tool 9 can be arranged in a clamping position relative to the plate-shaped workpiece 10.

[0074] After a firm clamping of the plate-shaped workpiece 10 has been achieved at least by the readjustment device 230, the gripper 23 is released. The gripper 23 is then moved away by a movement between the feed device 22 and the workpiece tables 28, 29. Preferably, the workpiece tables 28, 29 are moved in the Y direction by the feed device 22. This is shown by way of example in Fig. 13. During this moving away movement, the edge of the plate-shaped workpiece 10 assigned to the gripper 23 is preferably not guided completely out of the clamping jaws of the gripper 23, but rather still remains in the gap between the two clamping jaws.

[0075] Thereafter, a movement of the feed device 22, for example in the X-axis or the anti-X-axis, is controlled. This is shown in FIG. 14. After a predefined readjustment movement of the feed device 22 has been taken, a move-in movement is realized, which means that the edge of the plate-shaped workpiece 10 facing the gripper 23 is transferred back to the gripping position. In this case, when performing a readjustment for the first time, the move-in movement is preferably smaller than the move-away movement. This difference in movement is detected by the control device and taken into account during further processing of the plate-shaped workpiece 10. A reduction in the move-in movement compared to the move-away movement when performing a readjustment for the first time has the advantage that straightness errors of the edge of the plate-shaped workpiece 10 facing the gripper 23 can be compensated. During further subsequent readjustment processes following the first readjustment, the move-in movement and the move-away movement are preferably identical.

[0076] After the move towards action, the gripper 23 of the feeder 22 is closed. This is shown in FIG.

[0077] The readjustment device 230 is then transferred to the rest position 231 according to Fig. 5. In addition, if a clamping movement by the scraper or the upper tool 11 and the lower tool 9 was generated, this is also released. This is shown in Fig. 16. One or more processing cycles for the plate-shaped material 10 can then be started.

[0078] Figure 17 is a schematic view of an upper stroke drive 13 with the upper tool 11 arranged in a rest position relative to the lower tool 9. A plate-like workpiece 10 rests on the lower tool 9. This stroke drive 13 comprises, in a complementary manner to the stroke drive 13 shown diagrammatically in Figure 2, a scraper device 270 and a readjustment device 230. Provided on the double wedge 126, in particular on its lower face, is an upper pressure application device 234 of the readjustment device 230. A lower support device 235 is positioned and oriented so as to lie opposite and adjacent to the lower tool 9. This readjustment device 230 has been described in more detail in the preceding embodiment according to Figures 5 to 10.

[0079] The scraper device 270 comprises a scraper 271, which can be moved up and down or in height relative to the upper tool 11 by a scraper drive mechanism 272. This scraper drive mechanism 272 comprises a guide 273, in particular a column guide. This guide 273 consists, for example, of two or more guide rods oriented parallel to one another and guided in sleeves. Advantageously, at least one clamping sleeve 274 or a pair of clamping sleeves 274 is provided in the scraper drive mechanism 272 for fixing a controlled vertical position of the scraper 271 along the stroke axis 14. To move the scraper 271 up and down, a drive cylinder 275, in particular a pneumatic cylinder, is provided. The movement of the scraper 271 is provided independently of the movement of the stroke drive 13 or of the plunger 12 along the stroke axis 14.

[0080] FIG. 17 shows the scraper 271 in the rest position, in which it is arranged elevated with respect to the plate-shaped workpiece 10 or the lower tool 9, as well as the upper tool 11. By proceeding from such a position shown in FIG. 17, two different methods of readjusting the plate-shaped workpiece for machining on the machine tool can be selectively controlled. A first variant, in which only the readjusting device 230 is controlled to clamp and readjust the plate-shaped workpiece 10, is shown by way of example in FIGS. 11 to 14. The working position 232 of the readjusting device 230 according to the method described above with respect to FIGS. 11 to 16 is shown in FIG. 18. The scraper 271 and the upper tool 11 are still arranged at a distance with respect to the plate-shaped workpiece 10 and the lower tool 9 in the rest position. In the rest or upper position of the stroke drive 13, the upper pressure applicator 234 is transferred from the rest position 231 to the working position 232. The drive arrangement 17, by which the two drive side wedge mechanisms 122, 123 move towards each other, causes the double wedge 136 to descend, so that the upper pressure applicator 234 is moved into a clamping position relative to the lower pressure applicator 235 to fix the plate-shaped workpiece 10.

[0081] Further work steps are performed as described with respect to Figures 11-16.

[0082] According to a further variant of the method for reconditioning the plate-shaped workpiece 10, the plate-shaped workpiece 10 can be clamped and held against the lower tool 9 by both the reconditioning device 230 and the scraper 271 and / or the upper tool 11. A variant in which the reconditioning device 230 and the scraper 271 are shifted into a clamping position is shown in FIG. 19. The scraper 271 and the upper pressure applicator 234 are fed successively or simultaneously to the plate-shaped workpiece 10 such that the plate-shaped workpiece 10 is clamped and held against the upper and lower pressure applicators 234, 235 and the scraper 271 and the lower tool 9. To control the movement of the scraper 271 along the stroke axis 14, the clamping sleeve 274 is first released in order to control the actuating cylinder 275 consequently, in particular to apply pressure thereto. In the clamping position, the clamping sleeve 274 can be shifted into a clamping position such that the clamped position of the scraper 271 is maintained. In addition to or instead of the scraper 271 , the upper tool 11 can also be moved into a clamping position relative to the lower tool 9 .

[0083] After the plate-shaped workpiece 10 has been readjusted, the upper stroke drive 13 is moved along the stroke axis 14 to the initial or upper stroke position. The upper pressure applicator 234 is moved or pivoted to the rest position 231. The clamping sleeve 274 for the scraper 271 is released. The scraper 271 can be moved into a corresponding position for a subsequent processing operation. Further processing of the plate-shaped workpiece can then be controlled by the upper tool 11 and, if appropriate, with the scraper 271. [Explanation of symbols]

[0084] 1 Machine tools 2 Machine Frame 3 Upper horizontal frame member 4 Lower horizontal frame member 5 Vertical frame members 7 Frame internal space 8 Workpiece support part 9 Lower Tools 10 Workpiece 11 Upper Tools 12 Plunger 13 Stroke drive unit 14 Stroke axis 15 Numerical Controller 16 Positioning axis 17 Motor Drive Mechanism 18 Drive spindle 19 Guide rail 20 Guide shoe 21 Wedge mechanism 22 Feeding device 23 Gripper 25 Lower positioning axis 26 Motor Drive Configuration 27 Lower stroke drive 28 Workpiece table 29 Workpiece stand 81 Workpiece part 82 Connections 83 Cutting Gap 122 Drive side wedge mechanism element 123 Drive side wedge mechanism element 124 Output side wedge mechanism element 125 Output side wedge mechanism element 126 Output side double wedge 128 Motor rotary drive unit 129 Plunger Mount 130 Wedge Surface 131 Wedge Surface 132 Wedge Surface 133 Wedge Surface 134 Longitudinal guide 135 Longitudinal guide 136 Double Wedge 138 Motor Drive Unit 139 Motor Drive Unit 201 Laser processing equipment 202 Laser Source 203 Laser Beam 204 Beam Guide 206 Laser Cutting Head 207 Linear Drive Mechanism 210 Beam passing aperture 230 Readjustment device 231 Rest position 232 Operating position 234 Upper pressure application device 235 Lower pressure application device 240 Interface 241 Pressure Plunger 242 Connection mechanism 243 Drive Unit 244 Bearing 245 Piston rod 246 Lever Arm 247 Lever Arm 248 Axis 249 Holding Element 251 Stops 254 Cylindrical Housing 255 Pressure Pin 256 Disc spring assembly 260 Counter Bearing 265 Parallelogram Linkage 266 Acceptance Elements 270 Scraper device 271 Scraper 272 Scraper drive mechanism 273 Guide 274 Fastening sleeve 275 Drive cylinder

Claims

1. A readjustment device for a machine tool (1) for machining a plate-shaped workpiece (10), comprising: - an upper pressure application device (234) including at least pressure plungers (241) oriented at a distance from one another, a lower support device (235) having at least counter-bearings (260) spaced apart from one another, the lower support device (235) being oriented in an operating position (232) so as to clamp against the pressure plunger (241) of the upper pressure application device (234) to fix the plate-like workpiece (10); at least one drive device (243) by means of which said pressure plunger (241) of said upper pressure application device (234) can be transferred from a rest position (231) to said working position (232); at least two pressure plungers (241) of said upper pressure applicator (234) are coupled to each other and controlled to be movable or pivotable together between said rest position (231) and said working position (232); a readjustment device, in which the upper pressure application device (234) has a holding element (249) on which two parallel oriented pivot axes (248) are provided at a distance from one another for the pivotable arrangement of the pressure plunger (241).

2. 2. The readjustment device according to claim 1, wherein at least two pressure plungers (241) of the upper pressure application device (234) can be moved synchronously by a coupling or coupling mechanism (242), and the coupling mechanism (242) has the pressure plungers (241) on an output side and at least one drive device (243) on an input side.

3. 3. The readjustment device according to claim 1 or 2, wherein in the working position (232) the pressure plunger (241) is oriented facing the plate-shaped workpiece (10), and in the rest position (231) the pressure plunger (241) is moved upwards or pivoted laterally relative to the plate-shaped workpiece (10).

4. The reconditioning device of any one of claims 1 to 3, wherein the lower support device (235) is configured to be separated from the upper pressure application device (234).

5. 5. The readjustment device according to claim 1, wherein the pressure plunger (241) of the upper pressure application device (234) has a cylindrical housing (254) in which a pressure pin (255) is provided flexibly mounted, the pressure pin being guided such that when a clamping force is applied in the operating position (232), it can sink in the housing (254) against the force.

6. The reconditioning apparatus of claim 5, wherein a preload force storage element is provided within said cylindrical housing (254) for applying said force.

7. The readjustment device according to any one of claims 1 to 6, wherein the pivot axes (248) are spaced apart from one another on the holding element (249) of the upper pressure applicator (234) such that the pressure plungers (241) are arranged side-by-side in a rest position (231) and a horizontally oriented arrangement of the pressure plungers (241) is provided.

8. The readjustment device according to any one of the preceding claims, wherein in the operating position, the pressure plunger (241) abuts against a stop (251) which delimits an end position of the pressure plunger (241).

9. The readjustment device according to any one of the preceding claims, wherein the drive device (243) is rotatably mounted on a holding element (249).

10. The readjustment device according to any one of claims 1 to 9, wherein the upper pressure application device (234) can be actuated by a piston rod (245) of the drive device (243), the piston rod engaging with a coupling mechanism (242).

11. The readjustment device according to any one of claims 1 to 10, wherein at least one toggle lever mechanism is provided between a slide member or lever arm (246, 247) of a linkage (242) which engages with the pressure plunger (241) and the drive device (243).

12. The readjustment device according to any one of claims 1 to 11, wherein an interface (240) for attachment to an upper stroke drive (13) is provided on a retaining element (249) of the upper pressure applicator (234) and on the opposite side to the pressure plunger (241).

13. The readjustment device according to any one of claims 1 to 12, wherein a readjustment position can be set between a housing (254) of the pressure plunger (241) and a pressure pin (255) or between an upper stroke drive device (13) and an interface (240) of the upper pressure application device (234).

14. The readjustment device according to any one of claims 1 to 13, wherein the lower support device (235) has a load-bearing or support frame which can be fixed to the lower stroke drive device (27) for receiving at least two counter bearings (260).

15. Realignment device according to any one of the preceding claims, wherein the counter-bearing (260) is in the form of a rigid counter-bearing or in the form of a droppable or resiliently flexible counter-bearing.

16. A method for reconditioning a plate-shaped workpiece (10) for machining on a machine tool (1), comprising the steps of: - said plate-shaped workpiece (10) is positioned on a workpiece stage (28, 29) extending along the XY axis; - said plate-shaped workpiece (10) is held and moved along said worktable (28, 29) by a feeding device (22) including a number of grippers (23), said worktable being oriented relative to the machine frame (2); an upper tool (11) with an upper stroke drive (13) and a lower tool (9) with a lower stroke drive (27) are controlled so that they can move along the machine frame (2) and a plate-shaped workpiece (10) positioned between the upper tool (11) and the lower tool (9) is machined; A method, in which a reconditioning process is carried out by a reconditioning device (230) according to any one of claims 1 to 15 in order to recondition the plate-shaped workpiece (10) between two processing cycles.

17. 17. The method according to claim 16, wherein at the start of the readjustment process, the plate-shaped workpiece (10) is held fixed by the readjustment device (230), and the gripping position of the gripper (23) of the feeding device (22) relative to the plate-shaped workpiece (10) is released, and the feeding device (22) is moved relative to the plate-shaped workpiece (10) by a readjustment movement amount, and the plate-shaped workpiece (10) is then fixed by the gripper (23) of the feeding device (22) in the gripping position changed by the readjustment movement amount.

18. 18. The method according to claim 16 or 17, wherein in a first working step of the readjustment process, the upper pressure applicator (234) is moved to an upper end position relative to the machine frame (2) and the at least two pressure plungers (241) are then transferred from a rest position (231) to an active position (232).

19. The method according to any one of claims 16 to 18, wherein in a subsequent working step of the realignment process, the upper pressure applicator (234) is moved towards the plate-shaped workpiece (10) and the plate-shaped workpiece (10) is clamped and held between the upper pressure applicator (234) and the lower support device (235).

20. The method according to any one of claims 16 to 19, wherein after the plate-shaped workpiece (10) has been clamped and fixed by the readjustment device (230), the gripper (23) of the feeding device (22) is released and the plate-shaped workpiece (10) is controlled to move away from the gripper (23) of the feeding device (22) along the Y-axis.

21. 21. The method according to claim 20, wherein a movement of the feeding device (22) and / or a movement of the worktable (28, 29) are controlled to move the plate-shaped workpiece (10) away from the gripper (23).

22. The method according to any one of claims 16 to 21, wherein after the plate-shaped workpiece (10) has been moved away from the gripper (23), the feeding device (22) is moved along a readjustment movement amount and the plate-shaped workpiece (10) is then controlled to move towards the gripper (23) of the feeding device (22).

23. The method according to any one of claims 16 to 22, wherein in the case of a first realignment process, the amount of movement for moving the plate-shaped workpiece (10) away from the gripper (23) is controlled to be greater than the amount of movement for moving the plate-shaped workpiece (10) towards the gripper (23).

24. 24. The method according to claim 23, wherein for a subsequent realignment process, the amount of movement of the same movement is controlled to move the plate-shaped workpiece (10) towards and away from the gripper (23).

25. The method according to any one of claims 16 to 24, wherein after the readjustment movement of the feeding device (22) has been traversed, the plate-shaped workpiece (10) is clamped and held by the gripper (23) and at least the upper pressure application device (234) is moved along the Z-axis and then transferred to a rest position (231).

26. The method according to any one of claims 16 to 25, wherein during a reconditioning process process parameters of the feeding device (22) and / or the stroke drive (13, 27) are reduced.

27. A method according to any one of claims 16 to 26, wherein collision monitoring is performed before and / or during the realignment process.

28. The method according to any one of claims 16 to 27, wherein during the reconditioning process, clamping of the plate-shaped workpiece (10) by the upper tool (11) or by the scraper and the lower tool (9) is controlled sequentially or simultaneously with respect to the reconditioning device (230).

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