Re-adjustment device for a machine tool for machining a plate-shaped workpiece and method for re-adjusting a plate-shaped workpiece for machining in a machine tool

Abstract

The invention relates to a readjustment device and a method for a machine tool (1) for machining a plate-shaped workpiece (10), preferably a metal sheet, the readjustment device comprising an upper pressure application device (234) comprising at least pressure rams (241) oriented at a distance from one another, the readjustment device comprising a lower support device (235) having at least corresponding supports (260) arranged at a distance from one another and oriented in a working position (232) to fix the plate-shaped workpiece in a clamping manner with respect to the pressure rams of the upper pressure application device, the readjustment device comprising at least one drive device (243) by means of which the pressure rams of the upper pressure application device can be transferred from an idle position (231) to the working position, at least two pressure rams of the upper pressure application device being coupled to one another and controlled to move or pivot together between the idle position and the working position.

Description

TECHNICAL FIELD

[0001] The invention relates to a readjustment device for a plate-shaped workpiece in a machine tool for machining the plate-shaped workpiece, and also to a method for readjusting a plate-shaped workpiece for machining in a machine tool. BACKGROUND

[0002] CN 104550536 B discloses a machine tool for machining a plate-shaped workpiece by means of punching. The machine tool comprises an upper tool and a lower tool to machine a plate-shaped workpiece placed on a workpiece rest. The plate-shaped workpiece is held by means of a gripper by a feed device and is moved relative to the punching tool for machining purposes. In order to obtain a complete machining of the plate-shaped workpiece, a readjustment of the plate-shaped workpiece is necessary, which means that the clamping elements of the feed device are influenced relative to the clamping of the plate-shaped workpiece along the axis of the work plane. During the readjustment, it is necessary to fix the plate-shaped workpiece relative to the workpiece rest. For this purpose, two hydraulically controllable cylinders are provided, which are arranged spaced apart from one another and spaced apart from the punching tool. Pressure pieces are arranged at the extendable end of the piston rods, which are fed to corresponding support pieces positioned in the workpiece rest in order to obtain a clamping of the plate-shaped workpiece.

[0003] The two lifting cylinders, which can be controlled independently of one another, and the corresponding support pieces opposite the pressure pieces form the readjustment device.

[0004] This readjustment device has the disadvantage that it is not possible to generate a large force for fixing the plate-shaped workpiece. Furthermore, the cylinders require a large installation space, in particular a large structural height. SUMMARY

[0005] It is the task of the invention to propose a readjustment device for a machine tool for machining a plate-shaped workpiece, which enables a large holding force for fixing the plate-shaped workpiece in order to increase the machining safety. Furthermore, it is the task of the invention to propose a method for readjusting a plate-shaped workpiece for machining in a machine tool, by which the position of the plate-shaped workpiece is held with a high holding force in order to increase the machining safety.

[0006] The task is achieved by means of a readjustment device for a machine tool for machining a plate-shaped workpiece, the readjustment device comprising an upper pressure application device, which comprises at least two pressure rams arranged spaced apart from one another, the readjustment device comprising a lower support device, at least two corresponding supports of the lower support device arranged spaced apart from one another being positionable opposite the pressure rams, and the readjustment device comprising a drive device by means of which the pressure rams of the upper pressure application device can be transferred from an idle position into a working position, the at least two pressure rams of the upper pressure application device being coupled to one another and movable or pivotable together between the idle position and the working position. The coupling of the at least two pressure rams, which are moved together, in particular simultaneously or sequentially, from the idle position into the working position, makes it possible for the pressure rams to act on the plate-shaped workpiece with the same pressure or pressing force, respectively, in order to clamp the plate-shaped workpiece fixedly with respect to the corresponding supports opposite the pressure rams by clamping. This further makes it possible to prevent a rotational movement of the plate-shaped workpiece about the Z axis, that is to say a rotational movement in the X-Y plane, on the workpiece rest during the release and implementation of the clamping of the feed device. Furthermore, due to the movable arrangement from the idle position into the working position, this coupling of the at least two pressure rams of the upper pressure application device has the advantage that a compact construction height can be achieved, as a result of which further components of the machine tool, such as removal devices comprising clamping device, can be inserted and can be positioned between the upper tool and the plate-shaped workpiece in order to remove workpiece parts made from the plate-shaped workpiece.

[0007] According to an advantageous configuration of the readjustment device, the at least two pressure rams can be moved synchronously by means of a hinging mechanism or a coupling mechanism. This makes it possible to simplify the control of the two pressure rams, so that the two pressure rams can be moved together and simultaneously in order to exert a holding force on the plate-shaped workpiece.

[0008] Preferably, the at least two pressure rams of the upper pressure application device can be controlled by means of a hinging mechanism, wherein the pressure rams are arranged on the output side and the at least one drive device is arranged on the input side. By means of such a hinging mechanism, the at least one drive device can control a defined movement or pivoting movement of the pressure rams between the idle position and the working position.

[0009] Furthermore, preferably, the pressure rams are oriented facing towards the plate-shaped workpiece in the working position, in particular perpendicular to the plate-shaped workpiece, and are moved upwards or pivoted laterally with respect to the plate-shaped workpiece in the idle position. As a result, an increased free space between the upper tool and the plate-shaped workpiece and an accessibility to the plate-shaped workpiece are provided when the readjustment device is not in use, outside the readjustment process.

[0010] Furthermore, the lower support device is preferably configured to be decoupled or separated from the upper pressure application device. This makes it possible to simplify the structural design and to simplify the installation of the readjustment device in the machine tool.

[0011] Advantageously, the pressure ram of the upper pressure device comprises a cylindrical housing in which a pressure pin is arranged in a spring-supported manner. The pressure pin is guided in such a way that it sinks into the housing when a clamping force is applied to the plate-shaped workpiece. As a result, on the one hand a sufficient predetermined pressure can be applied and on the other hand tolerances can be compensated.

[0012] Preferably, a force storage element, in particular a preloaded spring assembly, is provided in the housing of the pressure ram for applying a force, in particular a spring force, by means of the pressure pin. Advantageously, a preloaded Belleville spring assembly is provided, as a result of which a defined force increase can be achieved in the case of a feed movement.

[0013] The upper pressure device of the readjustment device preferably has a base body or a holding element on which two pivot axes for the pivotable arrangement of the pressure ram are arranged spaced apart, which are oriented in a parallel manner, said pivot axes being able to be used to move the pressure ram from a retracted rest position into an extended work position. This pivotable arrangement of the pressure ram on the base body of the pressure device makes it possible to achieve a low or compact construction height in the rest position. Furthermore, the transfer of the pressure ram into the extended work position makes it possible for the longitudinal axis of the pressure ram to lie, for example, on the Z axis in order to subsequently achieve a high clamping force in the case of a feed movement of the upper tool for clamping a plate-shaped workpiece.

[0014] On the upper pressure device, the pivot axes are preferably arranged on the base body or the holding element spaced apart from one another, as a result of which the pressure rams are positioned behind one another in the retracted rest position, in particular arranged in a row and preferably oriented on a horizontally oriented line. As a result, the upper pressure device has a low height and a small width.

[0015] Furthermore, in the extended work position, the pressure rams are preferably abutted against end stops which delimit the pivot movement. This makes it possible for the force to be transmitted directly from the upper tool to the pressure rams via the base body and the end stops in the case of a stroke movement of the upper tool.

[0016] Preferably, a drive device is rotatably supported on the base body of the upper pressure device and controls the articulation mechanism to retract and extend the pressure rams between the rest position and the work position. Thereby, the upper pressure device is configured as a mounting assembly.

[0017] The drive device preferably comprises a stroke piston with an extendable piston rod by means of which the articulation mechanism is controlled. The stroke piston can be controlled in a hydraulic, pneumatic or electromagnetic manner. Alternatively, the drive device can also be configured as a gear mechanism, a cam control system or a linear drive.

[0018] Advantageously, a toggle mechanism is provided between the sliding member or lever arm of the articulation mechanism, which is in engagement with the pressure ram, and the drive device. As a result, in particular, a force assist can be carried out when the pressure ram is transferred to the rest position.

[0019] The upper pressure device of the readjustment device preferably has a connection interface on the base body or the holding element, which is opposite the pressure ram, which can be used to releasably fasten the pressure device on the upper stroke drive of the machine tool or on the upper tool. This makes it possible to simply and quickly install such an upper pressure device.

[0020] Furthermore, the readjustment position between the housing of the pressure ram and the pressure pin is preferably adjustable. This can be achieved, for example, by means of a spacing compensation element or the like. For example, the pressure pin can be composed in two parts, so that a spacing compensation element can be arranged between the two parts. Furthermore, alternatively, the readjustment position of the pressure ram arranged in the working position can be adjusted between the interface of the upper stroke drive and the upper pressure device. Preferably, a spacing compensation element having a preferably predetermined thickness level can also be arranged between the interface of the upper stroke drive and the upper pressure device.

[0021] Furthermore, in order to receive the at least two corresponding supports, the lower support device preferably has a support frame, which can be fastened on the lower stroke drive or on the lower tool. The support frame is preferably rigidly composed in order to, in particular, avoid a deflection in the plane of the workpiece rest.

[0022] According to a first embodiment, the corresponding supports of the lower support device can be configured as rigid corresponding supports. Alternatively, lowerable corresponding supports can also be used. By configuring lowerable corresponding supports, it is possible to achieve scratch-free machining, in particular in the case of softer plate-like workpieces.

[0023] The task of the application is also achieved by a method for readjusting a plate-like workpiece for machining in a machine tool, in which, in order to readjust the plate-like workpiece between two machining cycles, in which the plate-like workpiece is machined using a tool, a readjustment process is carried out by means of a readjustment device according to one of the above-mentioned embodiments. This method has the advantage that the pressure ram of the readjustment device is moved towards the corresponding supports of the lower support device and at the same time placed on the plate-like workpiece in order to clamp the plate-like workpiece between the pressure ram and the corresponding supports. As a result, a reliable clamping position can be assumed and held in order to carry out the readjustment process by means of a movement of a feed device, which clamps the plate-like workpiece during the machining of the plate-like workpiece and moves at least along the X-axis, at least along the X-axis of the workpiece rest.

[0024] It is preferably provided that at the beginning of the readjustment cycle the plate-shaped workpiece is held in a fixed manner in position by the readjustment device relative to the workpiece holder and the clamping position of the feed device relative to the plate-shaped workpiece is released and the feed device is moved relative to the plate-shaped workpiece by a readjustment distance and the plate-shaped workpiece is clamped by the gripper of the feed device in a clamping position which has been changed by the readjustment distance. As a result, complete machining of the plate-shaped workpiece can be achieved, in particular in the case of long plate-shaped workpieces whose length is greater than the movement distance of the feed device.

[0025] Furthermore, in a first working step of the readjustment process the upper pressure device of the readjustment device is preferably moved into an upper end position relative to the machine frame and the at least two pressure rams are subsequently transferred from the rest position into the working position. As a result, reliable extension or pivoting of the pressure rams into the working position can be achieved without collision with the plate-shaped workpiece 10.

[0026] In a subsequent working step of the readjustment process the upper pressure device is preferably moved towards the plate-shaped workpiece and the plate-shaped workpiece is held in a clamped manner between the upper pressure device and the lower support device. The movement of the upper pressure device along the Z axis makes it possible to achieve an unobstructed placement of the at least two pressure rams.

[0027] Subsequently, preferably after the plate-shaped workpiece has been clamped by the readjustment device, the gripper of the feed device is opened and the plate-shaped workpiece is controlled to move away from the gripper of the feed device along the Y axis. As a result of this movement away from the gripper, in particular from the jaws of the gripper, the straightness error of the side edges of the plate-shaped workpiece does not influence the clamping position of the plate-shaped workpiece in the readjustment device during the readjustment distance. When the plate-shaped workpiece is moved away, the end side of the plate-shaped workpiece which points towards the gripper is preferably not completely guided out of the jaws of the gripper, but only removed from the zero-stop in the jaws.

[0028] After the plate-shaped workpiece has been moved away from the gripper, the feed device is preferably moved along the adjustment distance and the plate-shaped workpiece is subsequently controlled to move towards the gripper of the feed device. The plate-shaped workpiece can thus be introduced again into the jaws of the gripper in order to provide an enlarged engagement surface for clamping the plate-shaped workpiece.

[0029] In particular, in the first readjustment process the movement distance of the plate-shaped workpiece when it is moved away from the gripper is controlled to be greater than the movement distance for moving the plate-shaped workpiece towards the gripper. This is the case in particular in the first readjustment process, since when the plate-shaped workpiece is clamped for the first time, the end edge of the plate-shaped workpiece which engages in the jaws rests against the zero-stop of the jaws of the gripper in order to have a defined orientation. In further subsequent readjustment processes, the movement distances for the clamping and unclamping are preferably identical.

[0030] Furthermore, preferably, after the readjustment distance, the plate-shaped workpiece is held in a clamped manner by the gripper and the upper pressure device is transferred to an idle position and a subsequent machining cycle is started.

[0031] Advantageously, during the readjustment process, the process parameters of the movement speed of the feed device and / or of the stroke drive can be reduced. This leads to an increased process safety, since the moment of inertia is reduced in the case of a reduced movement speed and / or acceleration.

[0032] A collision monitoring can be carried out before and / or during the readjustment process. In particular, this collision monitoring is carried out by the process controller. Thereby, it is achieved that the pressure ram of the upper pressure device and / or the corresponding bearing of the lower support device is positioned adjacent to a machined region of the plate-shaped workpiece. Such a machined region in the plate-shaped workpiece can be a cutout, a protrusion or a depression or a cheek or a groove or the like.

[0033] A further advantageous configuration of the method provides that, during the readjustment process, the clamping of the plate-shaped workpiece by the upper tool and the lower tool is controlled in parallel and / or successively with respect to the readjustment device. By this additional clamping of the plate-shaped workpiece between the upper tool and the lower tool or between the doctor blade on the upper tool and the lower tool, an additional fixation can be achieved. In particular, the pressure ram and the doctor blade or the upper tool are arranged in a triangular position with respect to each other. As a result, the plate-shaped workpiece can be held in a clamped manner at three points and an increased holding moment against a rotation of the plate-shaped workpiece in the XY plane can be obtained. BRIEF DESCRIPTION OF DRAWINGS

[0034] The application and further advantageous embodiments and improvements thereof will be described and explained in more detail below by means of examples shown in the drawings. The features which can be derived from the description and the drawings according to the application can be used on their own or in any combination with each other. In the drawings:

[0035] Figure 1 a perspective view of a machine tool is shown,

[0036] Figure 2 a schematic view of a stroke drive and a motor drive according to Figure 1 a basic design is shown,

[0037] Figure 3 a schematic top view of a machine tool with a workpiece rest according to Figure 1 is shown,

[0038] Figure 4 a schematic sectional view of the machine tool along the line IV-IV in Figure 1 is shown, wherein a workpiece rest surface is assigned to the machine base frame,

[0039] Figure 5perspective view of the readjustment device in the idle position,

[0040] Figure 6 perspective view of the readjustment device according to Figure 5 in the working position,

[0041] Figure 7 schematic cross-sectional view of the upper pressure device of the readjustment device in the idle position,

[0042] Figure 8 schematic cross-sectional view of the pressure device according to Figure 7 in the working position,

[0043] Figure 9 perspective view of an alternative embodiment of the upper pressure device of Figure 5 in the idle position,

[0044] Figure 10 perspective view of the pressure device according to Figure 9 in the working position,

[0045] Figures 11 to 16 schematic diagram for illustrating the readjustment process,

[0046] Figure 17 schematic diagram of the upper drive arrangement, wherein the readjustment device and the upper tool and the doctor blade are in the idle position relative to the plate-shaped workpiece,

[0047] Figure 18 schematic diagram of the upper stroke drive arrangement, wherein the readjustment device is in the working position, and

[0048] Figure 19 schematic diagram of the upper stroke drive arrangement according to Figure 17 , wherein the readjustment device and the doctor blade are in the working position. DETAILED DESCRIPTION

[0049] Figure 1 A machine tool 1 is shown which is configured as a punching press. The machine tool 1 comprises a carrying structure with a closed machine frame 2. The machine frame comprises two horizontal frame legs 3, 4 and two vertical frame legs 5 and 6. The machine frame 2 encloses a frame interior space 7 which, together with an upper tool 11 and a lower tool 9, forms a working area of the machine tool 1.

[0050] The machine tool 1 is used for machining plate-shaped workpieces 10 which, for the sake of simplicity, are not shown in the figures. The plate-shaped workpieces 10 are fed into the working area of the machine tool 1 by means of a feeding device 12. Figure 1A workpiece 10 to be machined is placed onto a workpiece support 8 arranged in the frame interior space 7. In the recess of the workpiece support 8, a lower tool 9, which is configured as a punch die, is mounted on the lower horizontal frame leg 4 of the machine frame 2. The punch die can be provided with a die opening. In the punching process, an upper tool 11, which is configured as a punch, sinks into the die opening of the lower tool configured as a punch die.

[0051] Instead of a punch and a punch die, the upper tool 11 and the lower tool 9 can also be used as a bending punch and a bending die for shaping the workpiece 10.

[0052] The upper tool 11 is fixed in a tool receiver on the lower end of a tappet 12. The tappet 12 is part of an upper stroke drive 13 by means of which the upper tool 11 can be moved in the 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 of the machine tool 1 as shown. Figure 1 The upper stroke drive 13 can be moved perpendicularly to the stroke axis 14 in the direction of the double arrow along a positioning axis 16. The positioning axis 16 extends in the Y direction of the coordinate system of the numerical controller 15. The upper stroke drive 13, which receives the upper tool 11, is moved along the positioning axis 16 by a motor drive 17.

[0053] The movement of the tappet 12 along the stroke axis 14 and the positioning of the upper stroke drive 13 along the positioning axis 16 is effected by means of a motor drive 17 in the form of a drive device 17 with a drive spindle 18, in particular a spindle drive, which extends in the direction of the positioning axis 16 and is fixedly connected to the machine frame 2. During movement along the positioning axis 16, the upper stroke drive 13 is guided on two guide rails 19 of the upper frame leg 3, for which guide rails it is possible to see in Figure 1 the visible guide rail 19. The remaining one of the guide rails 19 extends parallel to the visible guide rail 19 and is spaced apart from it in the direction of the X axis of the coordinate system of the numerical controller 15. A guide shoe 20 of the upper stroke drive 13 extends on the guide rail 19. The guide rail 19 and the guide shoe 20 are designed in such a way that the connection between the guide rail 19 and the guide shoe 20 can also receive a load acting in the vertical direction. Accordingly, the upper stroke drive 13 is suspended on the machine frame 2 by means of the guide shoe 20 and the guide rail 19. A further part of the upper stroke drive 13 is a wedge drive 21 by means of which the orientation of the upper tool 11 relative to the lower tool 9 can be adjusted.

[0054] The lower tool 9 is received displaceable along a lower positioning axis 25. This lower positioning axis 25 extends in the Y-axis direction of the coordinate system of the numerical controller 15. Preferably, the lower positioning axis 25 is oriented parallel to the upper positioning axis 16. The lower tool 9 can be moved along the positioning axis 25 directly at the lower positioning axis 16 by a motor drive 26. Alternatively or additionally, the lower tool 9 can also be arranged on a lower stroke drive device 27, which can be moved along the lower positioning axis 25 by the motor drive 26. This drive 26 is preferably configured as a spindle drive. The lower stroke drive device 27 can correspond in structure to the upper stroke drive device 13. Likewise, the motor drive 26 can correspond to the motor drive 17.

[0055] The lower stroke drive device 27 is likewise displaceably mounted on the guide rail 19 assigned to the lower horizontal frame leg 4. The guide shoe 20 of the lower stroke drive device 27 runs on the guide rail 19, so that the connection between the guide rail 19 and the guide shoe 20 on the lower tool 9 can also receive loads acting in the vertical direction. Correspondingly, the lower stroke drive device 27 is also suspended on the machine frame 2 by the guide shoe 20 and the guide rail 19 and is spaced apart from the guide rail 19 and the guide shoe 20 of the upper stroke drive device 13. The lower stroke drive device 27 can also comprise a wedge drive 21 by means of which the orientation or height of the lower tool 9 along the Z-axis can be adjusted.

[0056] Both the motor drive 17 for moving the upper tool 11 along the upper positioning axis 16 and the one or more motor drives 26 for moving the lower tool 9 along the lower positioning axis 25 can be controlled independently of one another by the numerical controller 15. Thus, the upper tool 11 and the lower tool 9 can be moved synchronously in the Y-axis direction of the coordinate system. Likewise, the upper tool 11 and the lower tool 9 can also be controlled for independent movement in different directions. This independent movement of the upper tool 11 and the lower tool 9 can be controlled simultaneously. By decoupling the movement between the upper tool 11 and the lower tool 9, greater flexibility can be achieved in the machining of the workpiece 10. In addition, the upper tool and the lower tool can also be configured in various ways to machine the workpiece 10.

[0057] One component of the upper stroke drive device 13 is a wedge drive 21, which is arranged in the upper positioning axis 16 and is configured to adjust the orientation or height of the upper tool 11 along the Z-axis. Figure 2The wedge gear 21 comprises two drive-side wedge gear elements 122, 123 and two driven-side wedge gear elements 124, 125. The two driven-side wedge gear elements are combined in a structural unit in the form of a driven-side double wedge 126. The tappet 12 is rotatably mounted on the driven-side double wedge 126 about the stroke axis 14. A motor rotary drive device 128 is mounted in the driven-side double wedge 126 and advances the tappet 12 about the stroke axis 14 as required. In this case, the tappet 12 can be rotated to the left and to the right in the double arrow in Figure 2 The tappet support 129 is shown schematically. On the one hand, the tappet support 129 allows low-friction rotational movement of the tappet 12 about the stroke axis 14, and on the other hand, the tappet support 129 supports the tappet 12 in the axial direction and correspondingly transmits loads acting on the tappet 12 in the direction of the stroke axis 14 into the driven-side double wedge 126.

[0058] The driven-side double wedge 126 is delimited by a wedge face 130 and a wedge face 131 of the driven-side gear element 125. Wedge faces 132, 133 of the drive-side wedge gear elements 122, 123 are opposite the wedge faces 130, 131 of the driven-side wedge gear elements 124, 125. By means of longitudinal guides 134, 135, the drive-side wedge gear element 122 and the driven-side wedge gear elements 124, 125, and the drive-side wedge gear element 123 and the driven-side wedge gear element 125, are guided so as to be movable relative to one another in the Y-axis direction, that is to say in the direction of the positioning axis 16 of the upper stroke drive device 13.

[0059] The drive-side wedge gear element 122 has a motor drive unit 138, and the drive-side wedge gear element 123 has a motor drive unit 139. The two drive units 138, 139 together form the spindle drive 17.

[0060] The motor drive units 138, 139 share Figure 1 The drive spindle 18 in the form of a drive device, shown in Fig. 1, is mounted on the machine frame 2 and is therefore located on the load-bearing structure side.

[0061] With respect to the motor drive units 138, 139, the drive-side wedge gear element 122, 123 is operated such that it moves along the positioning axis 16, for example, towards one another, as a result of which a relative movement between the drive-side wedge gear element 122, 123 on the one hand and the driven-side wedge gear element 124, 125 on the other hand is generated. As a result of this relative movement, the driven-side double wedge 126 and the tappet 12 supported thereon move along the stroke axis 14 downwards. The punch 11, for example, mounted on the tappet 12, performs a working stroke and here processes the workpiece 10 mounted on the workpiece shelf 28, 29 or the workpiece support 8. By movement of the drive-side wedge gear element 122, 123 in the opposite direction, the tappet 12 in turn can be raised or moved upwards along the stroke axis 14.

[0062] According to Figure 2 The above-described upstroke drive device 13 is preferably constructed identically to the downstroke drive device 27 and accommodates the lower tool 9.

[0063] Figure 3 A schematic view of the machine tool 1 according to Figure 1 is shown. The respective workpiece shelf 28, 29 extends laterally on the machine frame 2 of the machine tool 1. The workpiece shelf 28 can, for example, be assigned to a loading station (not shown in more detail) by means of which unprocessed workpieces 10 are placed onto the workpiece resting surface 28. Adjacent to the workpiece resting surface 28, 29, a feed device 22 is arranged, which comprises a plurality of grippers 23 in order to grip the workpieces 10 placed on the workpiece shelf 28. By means of the feed device 22, the workpieces 10 are guided in the X direction through the machine frame 2. Preferably, the feed device 22 can also be controlled to be movable in the Y direction. As a result, the workpieces 10 can be moved freely in the X-Y plane. Depending on the work task, the workpieces 10 can be moved not only in the X direction but also against the X direction by means of the feed device 22. This movement of the workpieces 10 can be adapted to the movement of the upper tool 11 and the lower tool 9 in the Y direction and in the opposite direction to the Y direction for the respective processing task.

[0064] The further workpiece shelf 29 is arranged opposite the workpiece shelf 28 on the machine frame 2. This further workpiece shelf can, for example, be assigned to an unloading station. Alternatively, the loading and unloading of unprocessed workpieces 10 and of processed workpieces 10 with workpiece portions 81 can also be assigned to the same workpiece shelf 28, 29.

[0065] Furthermore, the machine tool 1 can also comprise only Figure 3A laser processing device 201, in particular a laser cutting machine, is schematically shown in a top view. The laser processing device 201 can be configured as a CO2 laser cutting machine, for example. The laser processing device 201 comprises a laser source 202 generating a laser beam 204 which is guided by a schematically shown beam guide 204 to a laser processing head, in particular a laser cutting head 206 and focused therein. The laser beam 204 is then directed perpendicularly to the surface of the workpiece 10 through a cutting nozzle in order to process the workpiece 10. At the processing position, in particular the cutting position, the laser beam 204 acts on the workpiece 10, preferably together with a processing gas beam. The cutting point of the laser beam 204 incident on the workpiece 10 is adjacent to the processing point of the upper tool 11 and the lower tool 9.

[0066] 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 207 having a linear axis system. This linear axis system accommodating the laser cutting head 206 can be assigned, fastened or integrated into the machine frame 2. A beam passage opening 210 located in the workpiece shelf 28 is arranged below the working space of the laser cutting head 206. Preferably, a beam capture device for the laser beam 204 can be arranged below the beam passage opening 210. The beam passage opening 210 and, if necessary, also the beam capture device can be configured as a structural unit.

[0067] Alternatively, the laser processing device 201 can also have a solid-state laser as a laser source 202, the radiation of which is guided to the laser cutting head 206 by means of an optical cable.

[0068] Figure 4 A schematic sectional view according to line VI-VI in Figure 1 In this view of the machine tool 1, the vertical frame legs 5 and 6 and the upper horizontal frame leg 3 have been omitted. The view shows that the workpiece shelves 28, 29 extend directly onto the workpiece support 8 which at least partially encloses the lower tool 9. In the free space created between the workpiece support and the lower tool, the lower tool 9 can be moved along the lower positioning axis 25 in the Y direction and in the direction opposite to the Y direction. Furthermore, a beam passage opening 210 located in the workpiece shelf 28 is shown, provided that the machine tool 1 is equipped with a laser processing device 21.

[0069] For example, the worked piece 10 rests on the piece shelf 28, in which, in the worked piece, the piece portion 81 has been cut out, leaving a cut gap 83, for example by means of a punching process or by means of a laser beam process, with the exception of a remaining connection 82. Due to this remaining connection, the piece portion 81 is held in the piece 10 or in the remaining waste skeleton. In order to separate the piece portion 81 from the piece 10, the piece 10 is positioned relative to the upper tool 11 and the lower tool 9 by means of the feed device 22 for the spacing and the ejection step. In this case, the remaining connection 82 is separated by means of a punching stroke of the upper tool 11 relative to the lower tool 9. The piece portion 81 can be ejected downwards, for example by means of a partial lowering of the piece support 8. Alternatively, in the case of larger piece portions 81, the cut-out piece portion 81 can be transferred back to the piece shelf 28 or to the piece shelf 29 in order to unload the piece portion 81 and the waste skeleton. If necessary, small piece portions 81 can also be ejected through openings in the lower tool 9.

[0070] Figure 5 The readjustment device 230 is shown in the idle position 231. Figure 6 The readjustment device 230 is shown in the working position 232 according to the application. Figure 5 The readjustment device 230 comprises an upper pressure device 234 and a lower support device 235. The upper pressure device 234 is arranged on the upper stroke drive 13. The lower support device 235 is arranged on the lower stroke drive 27. The pressure device 234 and the support device 235 are preferably oriented adjacent to the upper tool 11 or the lower tool 9.

[0071] Figure 7 and Figure 8A sectional view of the upper pressure device 234 in the rest position 231 and in the working position 232 is shown. The upper pressure device comprises a mounting interface 240 for releasable arrangement on the stroke drive 13. Opposite the mounting interface, for example, two pressure tappets 241 are provided, which can be transferred from the rest position 231 to the working position 232 by means of a hinge mechanism 242. In the working position 232, the pressure tappets 241 face the plate-shaped workpiece 10. In particular, the pressure tappets are oriented perpendicularly with respect to the plane of the plate-shaped workpiece 10 in the working position 232. In order to control the movement of the pressure tappets 241, a drive 243 is provided. This drive 243 is preferably arranged rotatably about a bearing 244. As a result, the drive 243 can perform a corresponding pivoting movement during actuation of the hinge mechanism 242. In the rest position 232 of the pressure device 234, the pressure tappets 241 are preferably arranged in a row behind one another. In particular, the drives 243 are arranged in the same plane in the rest position. The drives 243 are, for example, configured as stroke pistons. The hinge mechanism 242 is actuated by a piston rod 245. The hinge mechanism 242 can be formed by a plurality of lever arms 246, 247 in order to control the pivoting movement of the pressure tappets 241 about position-fixed axes 248. These position-fixed axes 248 are provided on a base body or holding element 249, which is fixedly connected to the interface 240 and preferably also accommodates the rotational axis of the bearing 244.

[0072] In order to transfer the pressure tappets 241 from the rest position 231 to the working position 232, the drive 243 is actuated. For example, the piston rod 245 is retracted into the piston. The lever arms 246, 247 are controlled such that the pressure tappets 241 perform a pivoting movement of 90°. The end position of the pressure tappets 241 in the working position 232 is achieved by means of a preferably adjustable stop 251.

[0073] The hinge mechanism 242 can be configured in the manner of a toggle lever principle or can comprise such a toggle lever principle, so that an increased force can be applied in order to transfer the pressure tappets 241 into the horizontal position during the pivoting movement of the pressure tappets 241 from the working position 232 to the rest position 231.

[0074] The pressure tappets 241 are composed of a cylindrical housing 254, in which a pressure pin 255 is elastically supported. Preferably, a disc spring assembly 256 is provided between the housing 254 and the pressure pin 255, so that, on the one hand, a certain degree of flexibility can be applied and, on the other hand, the pressure tappets 241 can exert a sufficient contact pressure on the plate-shaped workpiece 10.

[0075] The lower support device 235 includes, for example, two corresponding support members 260. The number of corresponding support members 260 is adapted to the number of pressure rods 241. In the working position 232, the corresponding support members 260 are oriented relative to the longitudinal axis of the pressure rods 241.

[0076] According to the first embodiment, the corresponding support member 260 is fixedly mounted on the basic frame, which in turn can be fastened to the lower stroke drive device 27. Alternatively, the corresponding support member 260 may also be height-adjustable and / or retractable.

[0077] Figure 9 A perspective view showing an alternative embodiment of the upper pressure device 234 in the idle position 231. Figure 10 The basis for showing the working position 232 is shown. Figure 9 Alternative embodiments of the pressure application device 234.

[0078] This embodiment includes an alternative configuration of the hinge mechanism 242. In this embodiment, the hinge mechanism 242 is configured as a scissor-like device. Lever arms 246, 247 can be drawn from... Figure 9 The flat, folded arrangement is transformed according to Figure 10 The extension arrangement. A parallelogram linkage 265 can be arranged parallel to the lever arms 246, 247, such that, for example, the two pressure rods 241 arranged on the receiving element 266 can remain horizontally oriented during the retraction and extension movements of the hinge mechanism 242.

[0079] According to Figure 9 and Figure 10 In some embodiments, it is possible to use according to Figure 7 and Figure 8 The embodiment in the text uses a pressure rod 241. Alternatively, only a pressure pin 255 may be provided, which is height adjustable but fixedly mounted on the receiving element 266.

[0080] In this embodiment, in order to control the movement between the idle position 231 and the working position 232, for example, two drive devices 243 are arranged opposite each other, which act on the scissor-type device from each side to actuate the scissor-type device.

[0081] According to Figure 9 and Figure 10 In an alternative embodiment of the pressure application device 234, the support device 235 may correspond to the following: Figures 5 to 8 The above embodiments.

[0082] Figures 11 to 16 The various working steps of the readjustment process performed in the machine tool 1 by the readjustment device 230 according to one of the above embodiments are schematically shown.

[0083] Figure 11 The initial position of the readjustment process is schematically shown. If the movement distance of the feed device 22 in the X direction or in the opposite direction to the X direction is less than the length of the plate-shaped workpiece 10 to be processed, which extends in the X direction, the readjustment process needs to be initiated.

[0084] When the plate-shaped workpiece 10 is first tensioned or clamped by the gripper 23, the edge of the plate-shaped workpiece 10, which points into the gripper or faces the gripper 23, is positioned against the zero stop of the gripper 23. The zero stop is also used to orient the plate-shaped workpiece 10 when clamped for the first time. After one or more machining steps have been introduced into the plate-shaped workpiece 10 by the upper tool 11 and the lower tool 9, the readjustment process begins. According to Figure 11 The readjustment device 230, which is schematically shown in the idle position 231 according to Figure 5 is controlled and transferred into the working position 232. This is schematically shown in Figure 12 . In particular, the working position 232 of the readjustment device 230 is shown in Figure 6 .

[0085] Since the readjustment device 230 is arranged in the working position 232, the plate-shaped workpiece 10 is held fixed in place between the pressure tappet 241 and the opposite, corresponding bearing 260. The gripper 23 is closed at this time. In addition, the upper tool 11 or the doctor blade assigned to the upper tool 11 and the lower tool 9 can be arranged in the clamping position relative to the plate-shaped workpiece 10.

[0086] After secure clamping of the plate-shaped workpiece 10 has been achieved at least by the readjustment device 230, the gripper 23 is opened. Subsequently, the gripper 23 is de-pressurized by movement between the feed device 22 and the workpiece shelves 28, 29. Preferably, the workpiece shelves 28, 29 are moved in the Y direction by the feed device 22. This is shown, for example, in Figure 13 . When de-pressurized, the edge of the plate-shaped workpiece 10 assigned to the gripper 23 is preferably not completely guided out of the clamping jaws of the gripper 23, but remains in the gap between the two clamping jaws.

[0087] Subsequently, for example, the feed device 22 is moved along the X axis or opposite to the X axis. This is shown, for example, in Figure 14The closing of the clamps 23 of the feed device 22 takes place after the predetermined readjustment distance of the feed device 22 has been carried out, which means that the edge of the plate-shaped workpiece 10 facing the clamps 23 is transferred back to the clamped position. In this case, the closing distance is preferably smaller than the opening distance when the readjustment is carried out for the first time. The distance difference is detected by the control device and taken into account during further processing of the plate-shaped workpiece 10. The reduction of the closing distance compared to the opening distance when the readjustment is carried out for the first time has the advantage that straightness errors of the edge of the plate-shaped workpiece 10 facing the clamps 23 can be compensated. During further subsequent readjustment processes after the first readjustment, the closing distance and the opening distance are preferably identical.

[0088] After the closing, the clamps 23 of the feed device 22 are opened. This is shown in Figure 15 .

[0089] The readjustment device 230 is then transferred to the idle position 231 according to Figure 5 . If clamping by the doctor blade or the upper tool 11 and the lower tool 9 has additionally taken place, this is also released. This is shown in Figure 16 . One or more processing cycles for the plate-shaped workpiece 10 can then be started.

[0090] Figure 17 is a schematic view of the upper stroke drive 13, in which the upper tool 11 is arranged in the idle position relative to the lower tool 9. The plate-shaped workpiece 10 rests on the lower tool 9. The upper stroke drive 13 has a doctor blade device 270 and a readjustment device 230 in a manner which is supplementary to the upper stroke drive 13 which is shown schematically in Figure 2 . The readjustment device 230 has an upper pressure device 234 which is arranged on the double wedge 126, in particular on the lower side thereof. A lower support device 235 is positioned and oriented opposite and adjacent to the lower tool 9. The readjustment device 230 is described in more detail in the aforementioned embodiments according to Figures 5 to 10 .

[0091] The doctor blade device 270 comprises a doctor blade 271 which can be moved up and down or in height relative to the upper tool 11 by means of a doctor blade drive 272. The doctor blade drive 272 comprises a guide 273, in particular a column guide. The guide 273 consists, for example, of two or more guide rods which are oriented parallel to one another and guided in a sleeve. Advantageously, at least one clamping sleeve 274 or a pair of clamping sleeves 274 is arranged in the doctor blade drive 272 in order to fix the doctor blade 271 in a controlled vertical position along the stroke axis 14. For the up and down movement of the doctor blade 271, a drive cylinder 275, in particular a pneumatic cylinder, is provided. The movement of the doctor blade 271 is independent of the movement of the upper stroke drive 13 along the stroke axis 14 or of the movement of the tappet 12.

[0092] Figure 17 The doctor blade 271 is shown in the idle position, wherein the doctor blade, like the upper tool 11, is arranged elevated relative to the plate-shaped workpiece 10 or the lower tool 9. From this position, which is shown, Figure 17 Starting from this position, two different methods for selectively controlling the readjustment of the plate-shaped workpiece for machining in the machine tool can be selected, which differ from one another. In Figures 11 to 14 A first variant is shown by way of example in which only the readjustment device 230 is controlled to fix and readjust the plate-shaped workpiece 10. The working position 232 of the readjustment device 230 according to the method described above with respect to Figures 11 to 16 is shown in Figure 18 The doctor blade 271 and the upper tool 11 are still arranged in the idle position spaced apart from the plate-shaped workpiece 10 and the lower tool 9. In the idle position or upper position of the upper stroke drive 13, the upper pressure device 234 is transferred from the idle position 231 to the working position 232. By means of the drive device 17 by which the two drive-side wedge block transmissions 122, 123 are moved towards one another, the double wedge block 126 is lowered, so that the upper pressure device 234 is transferred relative to the lower support device 235 into the clamping position to fix the plate-shaped workpiece 10.

[0093] The further working steps are carried out as described with respect to Figures 11 to 16 .

[0094] According to a further variant of the method for readjusting the plate-shaped workpiece 10, the plate-shaped workpiece 10 can be held in a clamped manner by the readjustment device 230 and by the doctor blade 271 and / or the upper tool 11 relative to the lower tool 9. The variant in which the readjustment device 230 and the doctor blade 271 are transferred into the clamping position is shown in Figure 19 The doctor blade 271 and the upper pressure device 234 are fed to the plate-shaped workpiece 10 one after the other or simultaneously, so that the plate-shaped workpiece 10 is held in a clamped manner by the upper pressure device 234, the lower support device 235 and by the doctor blade 271 and the lower tool 9. In order to control the movement of the doctor blade 271 along the stroke axis 14, the clamping sleeve 274 is first released in order to then control the working cylinder 275, in particular to apply a pressure to the working cylinder. In the clamping position, the clamping sleeve 274 can be transferred into the clamping position, so that the clamping position of the doctor blade 271 is maintained. In addition to or as an alternative to the doctor blade 271, the upper tool 11 can be transferred into the clamping position relative to the lower tool 9.

[0095] After the plate-shaped workpiece 10 has been readjusted, the upstroke drive device 13 is transferred along the stroke axis 14 into the initial position or upstroke position. The upper pressure application means 234 are transferred or pivoted into the idle position 231. The clamping sleeve 274 for the doctor blade 271 is released. The doctor blade 271 can be transferred into the respective position for subsequent processing. Further processing of the plate-shaped workpiece by means of the upper tool 11 and possibly by means of the doctor blade 271 can then be controlled.

Claims

1. A readjustment device for a machine tool (1) for machining a plate-shaped workpiece (10), the readjustment device comprising - an upper pressure device (234) comprising pressure rams (241) oriented opposite one another at a distance, - a lower support device (235) having corresponding supports (260) arranged opposite one another at a distance, which in a working position (232) are oriented relative to the pressure rams (241) of the upper pressure device (234) to fix the plate-shaped workpiece (10) in a clamping manner, - at least one drive device (243) by means of which the pressure rams (241) of the upper pressure device (234) can be transferred from an idle position (231) to the working position (232), characterized in that - at least two pressure rams (241) of the upper pressure device (234) are coupled to one another and controlled to be able to move or pivot together between the idle position (231) and the working position (232), and - the upper pressure device (234) has a holding element (249) on which two parallel oriented pivot axes (248) are arranged at a distance from one another for the pivotable arrangement of the pressure rams (241).

2. The readjustment device of claim 1, wherein The at least two pressure rams (241) of the upper pressure device (234) can be moved synchronously by means of a hinged mechanism.

3. The readjustment device of claim 1, wherein, The pressure rams (241) are oriented facing the plate-shaped workpiece (10) in the working position (232) and are moved in height relative to the plate-shaped workpiece (10) or pivot laterally relative to the plate-shaped workpiece in the idle position (231).

4. A readjustment device according to one of claims 1 to 3, characterized in that The lower support device (235) is configured to be decoupled from the upper pressure device (234).

5. The readjustment device according to one of claims 1 to 3, characterized in that The pressure rams (241) of the upper pressure device (234) have a cylindrical housing (254) in which a pressure pin (255) is arranged in a flexible bearing, which is guided to sink into the housing (254) against force when a clamping force is applied in the working position (232).

6. The readjustment device of claim 5, wherein In the housing (254) a preloaded force storage element for applying force is arranged.

7. The readjustment device according to one of claims 1 to 3, characterized in that The pivot axes (248) are arranged at a distance from one another on the holding element (249) of the upper pressure device (234) such that the pressure rams (241) lie on a line in the idle position (231).

8. The readjustment device according to one of claims 1 to 3, characterized in that The pressure rams (241) abut against a stop (251) in the working position, which delimits an end position of the pressure rams (241).

9. The readjustment device according to one of claims 1 to 3, characterized in that The drive device (243) is rotatably supported on the holding element (249).

10. The readjustment device of claim 2, wherein, The upper pressure device (234) can be actuated by means of a piston rod (245) of the drive device (243), which engages with the hinged mechanism.

11. The readjustment device of claim 2, wherein, Between a sliding member or lever arm of the hinged mechanism, which engages with the pressure rams (241), and the drive device (243) at least one toggle lever mechanism is arranged.

12. The readjustment device according to one of claims 1 to 3, characterized in that On the holding element (249) of the upper pressure device (234) an interface (240) is arranged for mounting on an upper stroke drive.

13. The readjustment device of claim 12, wherein, The readjustment position between the upper travel drive and the interface (240) of the upper pressure device (234) is adjustable.

14. The readjustment device according to one of claims 1 to 3, characterized in that For receiving at least two corresponding supports (260), the lower support device (235) has a carrier frame or support frame, which can be fastened on the lower travel drive (27).

15. The readjustment device according to one of claims 1 to 3, characterized in that The corresponding supports (260) are configured as rigid corresponding supports or as corresponding supports which can be lowered or elastically yielded.

16. The readjustment device of claim 1, wherein, The sheet-like workpiece is a metal sheet.

17. The readjustment device of claim 2, wherein The articulated mechanism has the pressure tappets (241) on the output side and the at least one drive device (243) on the input side.

18. The readjustment device of claim 3, wherein, The pressure tappets (241) are oriented perpendicular to the sheet-like workpiece in the working position (232).

19. The readjustment device of claim 6, wherein, The preloading force storage element is a disc spring assembly.

20. The readjustment device of claim 7, wherein, The pressure tappets (241) are arranged behind one another in the rest position (231).

21. The readjustment device of claim 7, wherein, An arrangement of the horizontal orientation of the pressure tappets (241) is provided.

22. The readjustment device of claim 12, wherein, The interface (240) is opposite the pressure tappets (241).

23. The readjustment device of claim 5, wherein, The readjustment position between the housing (254) of the pressure tappet (241) and the pressure pin (255) is adjustable.

24. A method for readjusting a sheet-like workpiece (10) for machining in a machine tool (1), in which method - the sheet-like workpiece (10) is positioned on a workpiece rest (28, 29) extending along the X-Y axes, - the sheet-like workpiece (10) is held and moved along the workpiece rest (28, 29) by means of a feed device (22) comprising a plurality of grippers (23), the workpiece rest being oriented relative to the machine frame (2), - an upper tool (11) having an upper travel drive and a lower tool (9) having a lower travel drive (27) are controlled to be movable along the machine frame (2), and a sheet-like workpiece (10) positioned between the upper tool (11) and the lower tool (9) is machined, characterized in that - for readjusting the sheet-like workpiece (10) between two machining cycles, a readjustment process is carried out by means of a readjustment device (230) as claimed in one of claims 1 to 23.

25. The method of claim 24, wherein, At the start of the readjustment process, the sheet-like workpiece (10) is held in a fixed manner by the readjustment device (230), and the gripping positions of the grippers (23) of the feed device (22) are released relative to the sheet-like workpiece (10), and the feed device (22) is moved relative to the sheet-like workpiece (10) by a readjustment distance, and the sheet-like workpiece (10) is subsequently fixed in the gripping positions changed by said readjustment distance by the grippers (23) of the feed device (22).

26. The method of claim 24, wherein, In a first working step of the readjustment process, the upper pressure device (234) is moved relative to the machine frame (2) into an upper end position, and subsequently at least two pressure tappets (241) are transferred from the rest position (231) into the working position (232).

27. The method of any one of claims 24 to 26, wherein, In a subsequent work step of the readjustment process, the upper pressure device (234) is moved towards the sheet-like workpiece (10) and the sheet-like workpiece (10) is held in a clamped manner between the upper pressure device (234) and the lower support device (235).

28. The method of claim 27, wherein, After the sheet-like workpiece (10) is fixed in a clamped manner by the readjustment device (230), the gripper (23) of the feeding device (22) is opened and the sheet-like workpiece (10) is controlled to be moved away from the gripper (23) of the feeding device (22) along the Y-axis.

29. The method of claim 28, wherein, For moving the sheet-like workpiece (10) away from the gripper (23), a movement of the feeding device (22) and / or a movement of the workpiece shelf (28, 29) is controlled.

30. The method of claim 28, wherein, After the sheet-like workpiece (10) is moved away from the gripper (23), the feeding device (22) is moved over the readjustment distance and the sheet-like workpiece (10) is subsequently controlled to be moved towards the gripper (23) of the feeding device (22).

31. The method of claim 30, wherein, In the first readjustment process, the movement distance of the sheet-like workpiece (10) away from the gripper (23) is controlled to be greater than the movement distance of the sheet-like workpiece (10) towards the gripper (23).

32. The method of claim 31, wherein, The same movement distance is controlled in subsequent readjustment processes for moving the sheet-like workpiece (10) towards or away from the gripper (23).

33. The method of one of claims 24 to 26, characterized by After the readjustment distance of the feeding device (22) is passed, the sheet-like workpiece (10) is held in a clamped manner by the gripper (23) and at least the upper pressure device (234) is moved along the Z-axis and subsequently transferred to the idle position (231).

34. The method of any one of claims 24 to 26, wherein, During the readjustment process, process parameters of the feeding device (22) and / or process parameters of the upper and lower stroke drive are reduced.

35. The method of any one of claims 24 to 26, wherein, A collision monitoring is performed before and / or during the readjustment process.

36. The method of any one of claims 24 to 26, wherein, During the readjustment process, the clamping of the sheet-like workpiece (10) by the upper tool (11) or squeegee and the lower tool (9) is controlled in parallel and / or sequentially with respect to the readjustment device (230).

37. The method of claim 34, wherein, During the readjustment process, the process parameters of the feeding device (22) and / or the process parameters of the upper and lower stroke drive are movement speed, acceleration and / or jerk.

Images