METHOD AND MACHINE TOOL FOR PROCESSING PLATE-SHAPED WORKPIECES, IN PARTICULAR SHEETS

Description

[0001] Method and machine tool for machining plate-shaped workpieces, in particular sheet metal

[0002] The invention relates to a method and a machine tool for machining plate-shaped workpieces, in particular sheet metal.

[0003] Such a machine tool is known from EP 2 527 058 B1. This document discloses a machine tool in the form of a press for machining workpieces, wherein an upper tool is provided on a lifting device which can be moved relative to a workpiece to be machined along a lifting axis in the direction of the workpiece and in the opposite direction. A lower tool is provided in the lifting axis and opposite the upper tool and is positioned towards a lower side. A lifting drive device for a lifting movement of the upper tool is controlled by a wedge gear. The lifting drive device with the upper tool arranged thereon can be moved along a positioning axis. The lower tool is moved synchronously with the upper tool.

[0004] Furthermore, EP 2 722 194 A1 discloses a machine tool in the form of a press for machining workpieces, in which an upper tool is provided on a lifting device and can be moved along the lifting axis in the direction of the workpiece and a lower tool and in the opposite direction. After a workpiece part has been machined and separated from the plate-shaped workpiece, a table segment provided in the workpiece support for the workpiece to be machined can be lowered or pivoted downwards in order to eject the workpiece part separated from the workpiece. The workpiece part falls downwards due to a tilting movement and slides along the table segment in the ejection direction. The tool can then be picked up by a collecting container or the like.

[0005] DE 10 2009 018 512 A1 discloses a processing machine for processing plate-shaped workpieces. This machine has a transfer device in a work area, by means of which the workpiece part can be removed from the workpiece support after being separated from the workpiece. Subsequently, subsequent processing is carried out using a subsequent processing tool on the workpiece part removed from the workpiece support. After subsequent processing, the workpiece part is then returned to the workpiece support located in the work area of ​​the machine arrangement by means of this transfer device. The workpiece part stored on the workpiece support and the subsequent processing product stored on the workpiece support are removed from the work area of ​​the processing machine by means of a removal device, together with the workpiece support.

[0006] The invention is based on the object of proposing a method and a machine tool for machining workpieces, by means of which increased process reliability is enabled when removing at least one workpiece part separated from the workpiece.

[0007] This object is achieved by a method for machining plate-shaped workpieces, in particular sheet metal, in which an upper tool, which is movable along a lifting axis with a lifting drive device in the direction of a workpiece to be machined with the upper tool and in the opposite direction, is positioned with at least one motor drive arrangement along an upper positioning axis running perpendicular to the lifting axis, and in which a lower tool, which is aligned with the upper tool, is positioned with at least one motor drive arrangement along a lower positioning axis running perpendicular to the lifting axis of the upper tool. The workpiece rests on a workpiece support for machining. The upper and lower tools are moved in the interior of a machine frame, with the motor drive arrangements for moving the upper and lower tools being controlled by a controller.In this method, at least one workpiece part is severed from the workpiece. To remove the at least one workpiece part severed from the workpiece, after the last separating cut, the upper tool is moved outside of a spatial volume that extends above the severed workpiece part and is defined at least by a predetermined part of the base area of ​​the workpiece part in the workpiece plane and a perpendicular to the workpiece part in the direction of the upper positioning axis or by a predetermined part of the base area and an area outside the base area of ​​the workpiece part in the workpiece plane and a perpendicular to the workpiece part in the direction of the upper positioning axis. After the upper tool has moved outside of the spatial volume, the severed workpiece is removed.This method for removing at least one workpiece part separated from the workpiece has the advantage of increased process reliability. Removing the separated workpiece part does not require any movement of the workpiece part. After separation or free cutting, the workpiece part can remain in its position on the workpiece support until it is removed. Furthermore, an increased removal height is created within the machine frame of the machine tool above the workpiece part to be removed. This allows even larger workpiece parts to be removed reliably. This prevents the risk of collision when removing the workpiece from the upper tool.

[0008] According to a first embodiment of the method, the at least one workpiece part is removed using a gripping device that is moved above the workpiece and positioned in the spatial volume prior to gripping. Moving the upper tool outside the workpiece part prior to its removal, in particular outside a spatial volume above it, enables free accessibility above the workpiece part to be removed, thus enabling simplified insertion of the gripping device into the spatial volume to assume a gripping position for the workpiece part.Subsequently, a collision-free lifting movement of the gripping device can also be provided to the extent that the at least one workpiece part can be lifted relative to a workpiece or residual skeleton that may remain on the workpiece support, in order to then, for example, guide the workpiece part out of the spatial volume in a plane above the workpiece and transfer it to an unloading position.

[0009] An alternative embodiment of the method provides that before a table segment provided in the workpiece support is lowered to discharge the at least one workpiece part separated from the workpiece, the upper tool is moved outside the spatial volume. This has the advantage that a tilting movement of the workpiece part resting on it and to be discharged is possible when the table segment is lowered in the workpiece support, and the workpiece part can be discharged without collision. For larger workpiece parts, a workpiece edge opposite the discharge direction can perform a tilting movement.By pre-positioning the upper tool outside the spatial volume, especially the tilting area of ​​the workpiece part, the workpiece part can perform a free tilting movement when the table segment is lowered and is not hindered by the upper tool located above or the upper tool's stripper. This also prevents damage to the upper surface of the workpiece part during ejection.

[0010] Preferably, the upper tool is moved along the upper positioning axis outside the spatial volume of the workpiece part before the lowering movement of the table segment is initiated. A simple movement of the upper tool allows it to be quickly transferred to an area adjacent to the tilting area of ​​the workpiece part, thus enabling short cycle times for collision-free removal.

[0011] Furthermore, it is preferably provided that the lower tool is positioned stationary in the final working position after a final separating cut or freeing of a residual connection between the workpiece part and the workpiece and during the lowering of the table segment for ejecting the workpiece part. This also increases process reliability. After the workpiece part has been separated or freed from the workpiece, the workpiece part, which is loose from the workpiece, remains in its position on the workpiece support until the table segment is lowered. This prevents the workpiece part from becoming caught or shifted above or below the workpiece.

[0012] Furthermore, it is preferably provided that, for the removal of the workpiece part, the table segment is pivoted and lowered about a rotational axis aligned parallel to the upper positioning axis of the upper tool. This allows the table segment to be directly connected to the workpiece support surface, enabling safe removal after the table segment has been lowered, which is also referred to as a pivoting parts flap.

[0013] If only the separated workpiece part is ejected from the workpiece by lowering the table segment in the workpiece support, the spatial volume can be formed by a tilting area of ​​a workpiece edge of the workpiece part that is opposite to the ejection direction when the workpiece part is ejected.

[0014] Furthermore, it is preferably provided that, after the upper tool has been moved outside the tilting range of the workpiece part, a length of the workpiece part to be ejected is released during ejection, the length of which includes the length of the lowerable table segment, and a distance between the workpiece support surface and an interfering edge of the machine frame arranged above it is determined. The lateral movement of the upper tool increases the length of the workpiece parts to be ejected and expands the range of workpiece parts to be manufactured.

[0015] The object underlying the invention is further achieved by a machine tool which is preferably intended for carrying out the method described above. This machine tool comprises an upper tool which is movable along a lifting axis by means of a lifting drive device in the direction of a workpiece to be machined with the upper tool and in the opposite direction, and which is positionable by means of at least one motor drive arrangement along an upper positioning axis running perpendicular to the lifting axis, and which has a lower tool which is aligned with the upper tool and can be positioned by means of at least one motor drive arrangement along a lower positioning axis which is aligned perpendicular to the lifting axis of the upper tool. This machine tool has a machine frame, in the interior of which frame the upper and lower tools can be moved.The workpiece rests on a workpiece support of the machine tool for machining. The workpiece machine has a control system that controls the motor drive arrangements for moving the upper and lower tools. The control system allows the movement of the upper tool along the upper positioning axis and the movement of the lower tool along the lower positioning axis to be controlled independently of each other.To remove the at least one workpiece part severed from the workpiece, the upper tool can be positioned outside a spatial volume, wherein the spatial volume is defined at least by a predetermined portion of the base area of ​​the severed workpiece part in the workpiece plane and a perpendicular to the workpiece part in the direction of the upper positioning axis, or by a predetermined portion of the base area and an area outside the base area of ​​the workpiece part in the workpiece plane and a perpendicular to the workpiece part in the direction of the upper positioning axis. This provides the advantage of creating sufficient free space to enable collision-free removal of the workpiece part from the workpiece or from the workpiece support.

[0016] Preferably, the machine tool comprises a gripping device with at least one holding element, and the at least one holding element is movable into the space for gripping and removing the at least one workpiece part. Such a gripping device can be part of a handling device, thereby enabling automation during the removal and any subsequent processing of the workpiece parts.

[0017] Furthermore, it is preferably provided that, according to a first alternative, the gripping device is arranged on a machine frame, preferably an upper horizontal frame leg, and in particular the holding elements are movable with at least one linear axis of a linear drive. This enables a compact arrangement of the machine tool on the one hand and integration into an automated work process on the other. Alternatively, the gripping device can be provided on a handling device, which is designed as a standalone module and is assigned to a workpiece support. This also enables automated handling of the workpiece parts.

[0018] Alternatively, the machine tool can be provided with a table segment in the workpiece support which can be lowered relative to a workpiece support for ejecting a workpiece part. Before the table segment is lowered, a travel movement of the upper tool relative to the lower tool can be controlled so that the upper tool is positioned outside the spatial volume of the workpiece part to be ejected. This has the advantage that after the workpiece part has been separated and before the workpiece part is ejected, the upper tool can be moved outside a collision area by lowering the table segment. When the workpiece part is ejected, the lowering of the table segment can cause the workpiece part to tilt so that a workpiece edge lagging behind in the ejection direction is lifted relative to the workpiece support before it is ejected downwards.The movement space of the trailing workpiece edge forms the tilting area or volume. The upper tool does not impede such a tilting movement, as it is positioned outside the collision area or tilting area. This enables collision-free ejection. Furthermore, damage to the upper side of the workpiece part being ejected, especially the good part, is avoided.

[0019] A preferred embodiment of the machine tool provides that the table segment is pivotably mounted along a rotational axis. This rotational axis is aligned parallel to the upper positioning axis. This allows the upper tool to be moved outside the tilting range by controlling a travel movement of the upper tool along the upper positioning axis.

[0020] The invention and further advantageous embodiments and developments thereof are described and explained in more detail below with reference to the examples shown in the drawings. They show: Figure 1 a perspective view of the machine tool according to the invention, Figure 2 a schematic representation of the basic structure of a lifting drive device and a motor drive according to Figure 1 , Figure 3 a schematic diagram of a superimposed stroke movement in Y and Z directions of the ram according to Figure 1 , Figure 4 a schematic diagram of a further superimposed stroke movement in Y and Z directions of the ram according to Figure 1 , Figure 5 a schematic top view of the machine tool according to Figure 1 with workpiece support surfaces, Figure 6 a schematic side view of an upper and lower drive arrangement of the machine tool according to Figure 1 , Figure 7another schematic side view of the upper and lower drive arrangement according to Figure 6 , Figure 8 a perspective view of a tool for introducing a cutting gap into a workpiece to produce a workpiece part, Figure 9 a perspective view of a first process step for ejecting a workpiece part, Figure 10 a perspective view of a subsequent process step for ejecting a workpiece part, Figure 11 a schematic front view of Figure 10 , Figure 12 a perspective view of the workpiece part ejected from a workpiece plane, Figure 13 a perspective view of the machine tool with a workpiece support and a gripping device arranged on the machine frame and Figure 14 a perspective detailed view of holding elements of the gripping device in Figure 13in a removal position with an upper tool arranged adjacent to it.

[0021] In Figure 1 A machine tool 1 is shown, which is designed as a punch press. This machine tool 1 comprises a supporting structure with a closed machine frame 2. This comprises two horizontal frame legs 3, 4 and two vertical frame legs 5 and 6. The machine frame 2 encloses a frame interior 7, which forms the working area of ​​the machine tool 1 with an upper tool 11 and a lower tool 9.

[0022] The machine tool 1 is used for machining plate-shaped workpieces 10, which for the sake of simplicity are Figure 1are not shown and can be arranged in the frame interior 7 for processing purposes. A workpiece 10 to be machined is placed on a workpiece support 8 provided in the frame interior 7. The lower tool 9, for example in the form of a punching die, is mounted in a recess of the workpiece support 8 on the lower horizontal frame leg 4 of the machine frame 2. This punching die can be provided with a die opening. During punching, the upper tool 11, designed as a punching punch, plunges into the die opening of the lower tool designed as a punching die.

[0023] The upper tool 11 is fixed in a tool holder at a lower end of a ram 12. The ram 12 is part of a lifting drive device 13, by means of which the upper tool 11 can be moved in a lifting direction along a lifting axis 14. The lifting axis 14 runs in the direction of the Z-axis of the coordinate system of a Figure 1indicated numerical control 15 of machine tool 1. Perpendicular to the lifting axis 14, the lifting drive device 13 can be moved along a positioning axis 16 in the direction of the double arrow. The positioning axis 16 runs in the direction of the Y-axis of the coordinate system of the numerical control 15. The lifting drive device 13, which holds the upper tool 11, is moved along the positioning axis 16 by means of a motor drive 17.

[0024] The movement of the ram 12 along the stroke axis 14 and the positioning of the stroke drive device 13 along the positioning axis 16 are carried out by means of a motor drive 17 in the form of a drive arrangement 17, in particular a spindle drive arrangement, with a drive spindle 18 running in the direction of the positioning axis 16 and firmly connected to the machine frame 2. The stroke drive device 13 is guided during movements along the positioning axis 16 on three guide rails 19 of the upper frame leg 3, of which Figure 1two guide rails 19 can be seen. The one remaining guide rail 19 runs parallel to the visible guide rail 19 and is spaced from it in the X-axis direction of the coordinate system of the numerical control 15. Guide shoes 20 of the lifting drive device 13 run on the guide rails 19. The mutual engagement of the guide rail 19 and the guide shoes 20 is such that this connection between the guide rails 19 and the guide shoes 20 can also absorb a load acting in the vertical direction. Accordingly, the lifting device 13 is suspended from the machine frame 2 via the guide shoes 20 and the guide rails 19. A further component of the lifting drive device 13 is a wedge gear 21, by means of which a position of the upper tool 11 relative to the lower tool 9 can be adjusted.

[0025] The lower tool 9 is mounted so as to be movable along a lower positioning axis 25. This lower positioning axis 25 runs in the direction of the Y-axis of the coordinate system of the numerical control 15. The lower positioning axis 25 is preferably aligned parallel to the upper positioning axis 16. The lower tool 9 can be moved directly along the lower positioning axis 16 using a motor drive arrangement 26 along the positioning axis 25. Alternatively or additionally, the lower tool 9 can also be provided on a lifting drive device 27, which can be moved along the lower positioning axis 25 by means of the motor drive arrangement 26. This drive arrangement 26 is preferably designed as a spindle drive arrangement. The lower lifting drive device 27 can correspond in structure to the upper lifting drive device 13. The motor drive arrangement 26 can also correspond to the motor drive arrangement 17.

[0026] The lower lifting drive device 27 is slidably mounted on guide rails 19 assigned to the lower horizontal frame leg 4. Guide shoes 20 of the lifting drive device 27 run on the guide rails 19, so that the connection between the guide rails 19 and the guide shoes 20 on the lower tool 9 can also absorb a load acting in the vertical direction. Accordingly, the lifting drive device 27 is also suspended via the guide shoes 20 and the guide rails 19 on the machine frame 2 and spaced from the guide rails 19 and guide shoes 20 of the upper lifting drive device 13. The lifting drive device 27 can also include a wedge gear 21, by means of which the position or height of the lower tool 9 can be adjusted along the Z-axis.

[0027] The numerical control 15 allows both the motor drives 17 for moving the upper tool 11 along the upper positioning axis 16 and the motor drive(s) 26 for moving the lower tool 9 along the lower positioning axis 25 to be controlled independently of one another. Thus, the upper and lower tools 11, 9 can be moved synchronously in the Y-axis of the coordinate system. Likewise, independent movement of the upper and lower tools 11, 9 can also be controlled in different directions. This independent movement of the upper and lower tools 11, 9 can be controlled simultaneously. By decoupling the movement between the upper tool 11 and the lower tool 9, increased flexibility in the machining of workpieces 10 can be achieved. The upper and lower tools 11, 9 can also be designed in a variety of ways for machining the workpieces 10.

[0028] A component of the lifting drive device 13 is the wedge gear 21, which is Figure 2 The wedge gear 21 comprises two drive-side wedge gear elements 122, 123, as well as two output-side wedge gear elements 124, 125. The latter are structurally combined to form a structural unit in the form of an output-side double wedge 126. The plunger 12 is rotatably mounted about the stroke axis 14 on the output-side double wedge 126. A motorized rotary drive device 128 is housed in the output-side double wedge 126 and moves the plunger 12 along the stroke axis 14 as required. Both a left-hand and a right-hand rotation of the plunger 12 is possible according to the double arrow in Figure 2possible. A tappet bearing 129 is shown schematically. On the one hand, the tappet bearing 129 allows low-friction rotational movements of the tappet 12 about the stroke axis 14. On the other hand, the tappet bearing 129 supports the tappet 12 in the axial direction and accordingly transfers loads acting on the tappet 12 in the direction of the stroke axis 14 to the output-side double wedge 126.

[0029] The output-side double wedge 126 is delimited by a wedge surface 130 and by a wedge surface 131 of the output-side gear element 125. Wedge surfaces 130, 131 of the output-side wedge gear elements 124, 125 are opposite wedge surfaces 132, 133 of the drive-side wedge gear elements 122, 123. Longitudinal guides 134, 135 guide the drive-side wedge gear element 122 and the output-side wedge gear element 124, as well as the drive-side wedge gear element 123 and the output-side wedge gear element 125, so that they can move relative to one another in the direction of the Y-axis, i.e., in the direction of the positioning axis 16 of the lifting drive device 13.

[0030] 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. Both drive units 138, 139 together form the spindle drive arrangement 17.

[0031] The motor drive units 138, 139 have in common the Figure 1 shown drive spindle 18 as well as the lifting drive device 13, 27 mounted on the machine frame 2 and consequently on the supporting structure side.

[0032] The drive-side wedge gear elements 122, 123 are operated by the motor drive units 138, 139 in such a way that they move, for example, toward one another along the positioning axis 16, resulting in a relative movement between the drive-side wedge gear elements 122, 123 on the one hand and the output-side wedge gear elements 124, 125 on the other. As a result of this relative movement, the output-side double wedge 126 and the ram 12 mounted thereon are moved downward along the stroke axis 14. The punching punch mounted on the ram 12, for example as an upper tool 11, performs a working stroke and in the process machines a workpiece 10 mounted on the workpiece support 28, 29 or the workpiece support 8. By an opposite movement of the drive wedge elements 122, 123, the ram 12 is in turn raised or moved upwards along the stroke axis 14.

[0033] The previously described lifting drive device 13 according to Figure 2is preferably constructed identically as a lower lifting drive device 27 and accommodates the lower tool 9.

[0034] In Figure 3a schematic diagram of a possible lifting movement of the ram 12 is shown. The diagram shows a stroke profile along the Y-axis and the Z-axis. By superimposing the control of a travel movement of the ram 12 along the stroke axis 14 and along the positioning axis 16, for example, an oblique lifting movement of the lifting ram 12 downwards towards the workpiece 10 can be controlled, as shown by the first straight line A. Subsequently, after the stroke has been carried out, the ram 12 can, for example, be lifted vertically, as shown by the straight line B. This is followed, for example, by a travel movement exclusively along the Y-axis according to the straight line C in order to position the ram 12 for a new working position relative to the workpiece 10. The previously described work sequence can then be repeated, for example.If the workpiece 10 is moved on the workpiece support surface 28, 29 for a subsequent machining step, a travel movement along the straight line C can also be omitted.

[0035] The diagram in Figure 3 The possible stroke movement of the ram 12 on the upper tool 11 shown is preferably combined with a stationary lower tool 9. The lower tool 9 is positioned within the machine frame 2 in such a way that at the end of a working stroke of the upper tool 11, the upper and lower tools 11, 9 assume a defined position.

[0036] This exemplary superimposed stroke curve can be controlled for both the upper tool 11 and the lower tool 9. Depending on the machining of the workpiece 10, a superimposed stroke movement of the upper tool and / or lower tool 11, 9 can be controlled.

[0037] In Figure 4is a schematic diagram showing a stroke movement of the plunger 12 according to the exemplary line D along a Y-axis and a Z-axis. Figure 3 In this embodiment, it is provided that a stroke movement of the ram 12 can follow a curved or arcuate path by controlling a superposition of the travel movements in the Y and Z directions accordingly by the controller 15. Such a flexible superposition of the travel movements in the X and Z directions allows specific machining tasks to be solved. The control of such a curved path can be provided for the upper tool 11 and / or lower tool 9.

[0038] In Figure 5 is a schematic view of the machine tool 1 according to Figure 1shown. A workpiece support 28, 29 extends laterally along the machine frame 2 of the machine tool 1. The workpiece support 28 can, for example, be assigned to a loading station (not shown in detail), through which unmachined workpieces 10 are placed onto the workpiece support 28. Adjacent to the workpiece support 28, 29 is a feed device 22 which comprises a plurality of grippers 23 for gripping the workpiece 10 placed on the workpiece support 28. By means of the feed device 22, the workpiece 10 is guided through the machine frame 2 in the X direction. Preferably, the feed device 22 can also be controlled so that it can be moved in the Y direction. This allows for free movement of the workpiece 10 in the XY plane. Depending on the work task, the workpiece 10 can be moved by the feed device 22 both in the X direction and counter to the X direction.This movement of the workpiece 10 can be adapted to a movement of the upper tool 11 and lower tool 9 in and against the Y direction for the respective machining task.

[0039] Opposite the workpiece support 28, another workpiece support 29 is provided on the machine frame 2. This can, for example, be assigned to an unloading station. Alternatively, the loading and unloading of the unmachined workpiece 10 and the machined workpiece 10 with workpieces 81 can also be assigned to the same workpiece support 28, 29.

[0040] The machine tool 1 can further comprise a laser processing device 201, in particular a laser cutting machine, which is shown only schematically in a plan view in Figure 5This laser processing device 201 can be designed, for example, as 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 means of a schematically illustrated beam guide 204 to a laser processing head, in particular laser cutting head 206, and focused therein. The laser beam 204 is then directed through a cutting nozzle perpendicular to the surface of the workpiece 10 in order to process the workpiece 10. The laser beam 203 acts on the workpiece 10 at the processing location, in particular the cutting location, preferably together with a process gas jet. The cutting point at which the laser beam 203 impinges on the workpiece 10 is adjacent to the processing location of the upper tool 11 and lower tool 9.

[0041] The laser cutting head 206 is movable by a linear drive 207 with a linear axis system, at least in the Y direction, preferably in the Y and Z directions. This linear axis system, which accommodates the laser cutting head 206, can be assigned to the machine frame 2, attached to it, or integrated therein. A beam passage opening can be provided in the workpiece support 28 below a working area of ​​the laser cutting head 206. A beam capture device for the laser beam 21 can preferably be provided below the beam passage opening. The beam passage opening and, if applicable, the beam capture device can also be designed as a single structural unit.

[0042] The laser processing device 201 can alternatively also have a solid-state laser as the laser source 202, the radiation of which is guided to the laser cutting head 206 by means of a fiber optic cable.

[0043] The workpiece support 28, 29 can extend directly to the workpiece support 8, which at least partially surrounds the lower tool 9. Within a free space created therebetween, the lower tool 9 can be moved along the lower positioning axis 25 in and against the Y direction.

[0044] For example, a machined workpiece 10 rests on the workpiece support 28, in which a workpiece part 81 has been cut free from a cutting gap 83, for example by punching or laser beam machining, except for a residual connection 82. This residual connection holds the workpiece 81 in the workpiece 10 or the remaining residual skeleton. To separate the workpiece part 81 from the workpiece 10, the workpiece 10 is positioned by means of the feed device 22 to the upper and lower tools 11, 9 for a punching and ejection step. The residual connection 82 is severed by a punching stroke of the upper tool 11 to the lower tool 9. The workpiece part 81 can be ejected, for example, by partially lowering the workpiece support 8.Alternatively, for larger workpiece parts 81, the cut-out workpiece part 81 can be transferred back to the workpiece support 28 or to the workpiece support 29 to unload the workpiece part 81 and the remaining skeleton. Smaller workpiece parts 81 can also be ejected through an opening in the lower tool 9, if necessary.

[0045] In Figure 6 A simplified schematic representation of an end face of the upper drive assembly 17 and the lower drive assembly 26 with a workpiece 10 arranged therebetween is shown. This view is taken in the Y direction of the upper and lower drive assemblies 17, 26.

[0046] The Figure 7 shows a further schematic side view of the drive arrangements 17, 26 according to Figure 6 in X-direction.

[0047] The upper and lower drive assemblies 17, 26 are aligned with one another, for example, with respect to an upper lifting axis 14 and a lower lifting axis 30. As a result of a previous machining of the workpiece 10, at least one workpiece part 81 is at least partially cut free and fixed to the workpiece 10 via a residual connection 82 or completely separated from the workpiece 10. The workpiece part 81 has, for example, a rectangular contour. A spatial volume 220 is formed by at least a predetermined part of the base area of ​​the workpiece part 81 and a perpendicular thereto in the direction of the upper positioning axis 16, which spatial volume is limited in height by a distance between the workpiece 10 and an underside of the upper horizontal frame leg 3. The spatial volume 220 can also be formed by the base area of ​​the workpiece part 81 and a perpendicular thereto in the direction of the upper positioning axis 16.The spatial volume 220 can also be defined by the base area and a lateral extension beyond the base area of ​​the workpiece 81 and a perpendicular thereto in the direction of the upper positioning axis 16. The spatial volume 220 can also be formed by a predetermined portion of the base area of ​​the workpiece part 81 and by a lateral extension beyond the base area of ​​the workpiece part 81 and a perpendicular thereto. The lateral extension extends in and opposite to the upper positioning axis 16, along which the upper tool 11 is movable.

[0048] For the removal of the workpiece part 81, it is provided that the upper tool 11 is positioned outside the spatial volume 220, so that this spatial volume 220 above the workpiece 10 and below the upper horizontal frame leg 3 is freely accessible and can be used for the removal of the workpiece part 81. By moving the upper tool 11 outside the spatial volume 220 before the removal of the workpiece part 81, the removal height between the workpiece plane and a bottom side of the upper horizontal frame leg 3 is reduced compared to the upper tool 11 remaining in the spatial volume 220, as is shown in the Figures 6 and 7 shown, increased.

[0049] This free space volume 220 enables a collision-free removal of the workpiece part 81 by discharging the workpiece part 81 downwards via a table segment 285, as described below in the Figures 8 to 12or by removal by means of a gripping device 292, as described below with reference to Figures 13 and 14 described.

[0050] In Figure 8 A simplified schematic representation of a workpiece 10 resting on the workpiece support 28, 29 is shown, which is being machined by an upper and lower tool 9, 11. During machining, the workpiece 10 is moved in and against the X direction by the grippers 23 to create a cutting gap 83. The upper and lower tools 9, 11 are moved accordingly in and against the Y direction along the upper and lower positioning axes 16, 25.

[0051] The workpiece support 28 comprises a table segment 285, which forms part of the workpiece support 28. This table segment 285 can be lowered relative to the workpiece support surface 28 for the discharge of workpiece parts 81. The table segment 285 is pivotally mounted about a rotation axis 286, which is aligned parallel to the positioning axis 16, 25. The table segment 285 preferably extends over the entire width of the workpiece support 28, 29 in the Y direction. The table segment 285 is flush with the adjacent workpiece support 8 due to the pivotable connection, so that after a lowering movement, the workpiece part 81 can be discharged downwards, as is the case, for example, in Figure 12 The discharge direction is shown by arrows 287.

[0052] For small workpiece parts 81, whose length corresponds to or is shorter than the length of the table segment 285, the last separating cut can be in the Y-axis. For larger workpiece parts 81, it is preferably provided that the last separating cut lies in an X-axis, that is, starting from the beginning of a cutting gap 83 according to arrow 288 ( Figure 8 ) and producing the cutting gap 83, for example, in a counterclockwise direction, a workpiece edge 289 opposite the table segment 285 with respect to the rotation axis 286 is cut. This workpiece edge 289 is oriented, for example, in the Y direction. Subsequently, a movement of the workpiece 10 in the X direction is initiated in order to cut the workpiece part 81 according to arrow 290 ( Figure 8 ) completely. As a result, the workpiece edge 289 lies outside the length of the table segment 285 and on the workpiece support 29.

[0053] For collision-free removal of such a workpiece part 81, the upper tool 11 is moved along the upper positioning axis 16. The lower tool 9 is held stationary relative to the lower positioning axis 25 in the last working position for separating or cutting free the workpiece part 81. The upper tool 11 is moved by a distance relative to the lower tool 9 ( Figure 9 ), so that it is positioned outside the spatial volume 220. This has the advantage that during a tilting movement of the workpiece edge 289 about the rotation axis 286 after the lowering of the table segment 285, the workpiece part 81 does not collide with the upper tool 11.

[0054] A first phase of the discharge after lowering the table segment 285 is shown in perspective in Figure 10 and in a front view in Figure 11The workpiece 10 resting on the table segment 85, which has a section with a final workpiece edge 289 that lies outside the support surface of the table segment 285, undergoes a tilting movement when the table segment 285 is lowered. This is due to the fact that the center of gravity of the workpiece part 81 lies in the surface of the table segment 285. As a result, the workpiece edge 289 opposite in the discharge direction 287 is pivoted relative to a workpiece plane in the direction of the upper frame leg 3. Such a maximum tilting movement of the workpiece part 81 is Figure 11shown. Due to the offset of the position axes 35 of the upper tool 11 relative to the position axis 48 of the lower tool 9, the upper tool 11 is positioned outside the collision area or the tilting area of ​​the workpiece part 81. This allows the tilting movement to be carried out unhindered within the free space 220, and the workpiece part 81 can be discharged downwards.

[0055] A final phase of the discharge process is in Figure 12 shown. The workpiece edge 289 has already been lowered and positioned below the workpiece plane of the workpiece 10. Subsequently, after the workpiece part 81 has been removed, the table segment 285 can be closed again to form a closed workpiece support 28, and the upper and lower tools 11, 9 can be moved into position relative to the workpiece 10 for further machining.

[0056] In Figure 13 is in perspective an alternative embodiment of the machine tool to Figure 1and 5 This machine tool 1 differs from the Figure 1 and Figure 5 that instead of or in addition to the laser processing device 201 according to Figure 5 a gripping device 292 is provided on the machine frame 2, which is controlled to be movable above the workpiece 10 via a linear drive 207, which is also arranged on the upper horizontal frame leg 3. The laser processing device 201 can be provided on an opposite side wall on the horizontal frame leg 3 of the machine tool 1 and can have a similar structure as in Figure 5 have.

[0057] The linear drive 207 for the gripping device 292 can have a horizontal linear axis 293, along which a vertical linear axis 294 is movable along the Y-direction. The gripping device 292 is arranged on the vertical linear axis 294 and comprises holding elements 295 facing the workpiece 10. The holding elements 295 can be arranged and / or controlled individually or in groups. These holding elements 295 can be, for example, magnetic suction cups, vacuum suction cups, or electro-adhesion suction cups. The individual groups of holding elements 295 can also be controlled individually in order to successively remove one or more workpiece parts 81 separated from the workpiece 10.

[0058] The gripping device 292 is positioned in the spatial volume 220 above the workpiece part 81 to be removed with at least one of the holding elements 295 for removing at least one workpiece part 81. The upper tool 11 has been moved outside the spatial volume 220 before the holding elements 295 are positioned in the spatial volume 220, as can be seen from a schematically enlarged view according to Figure 14 In this perspective view according to Figure 14 the side of the machine frame 2 opposite the gripping device 292 is shown.

[0059] The upper tool 11 is positioned outside the spatial volume 220 of the severed workpiece part 81 by the upper drive assembly 17. This allows the holding elements 295 to be retracted and positioned unhindered into a position above the workpiece part 81 or the workpiece parts 81 in the spatial volume 220. By moving the upper tool 11 laterally before removing the at least one workpiece part 81, the removal height between the workpiece 10 and an underside of the upper horizontal frame leg 3 is increased. In addition, the at least one workpiece part 81 can rest motionless on the workpiece support 28, 29 after separation. During the movement of the upper tool 11 outside the spatial volume 220, the lower tool 9 remains stationary in the position in which the last separating cut for the workpiece part 81 took place.

[0060] To remove the at least one workpiece part 81, the at least one holding element 295 is lowered. The at least one workpiece part 81 is gripped, subsequently triggering a lifting movement of the holding elements 295 in the Z direction. The workpiece part 81 is positioned above the workpiece plane of the workpiece 10. Subsequently, the gripping device 292 with its holding elements 295 can be guided out of the spatial volume 220, and the workpiece parts can be transferred to an unloading position. Such a gripping device 292 can increase automation.

[0061] In an alternative and not shown embodiment of the machine tool in Figure 13It can be provided that the gripping device 292 and the linear drive 207 with the at least one linear axis 293, 294 are designed as an independent handling device. This handling device can be assigned to one of the two workpiece supports 28, 29 and positioned adjacent to or adjacent thereto. The gripping device 292 of such a handling device can be designed analogously to the Figure 13 and 14 described gripping device 292 for removing the workpiece parts 81 can be used and controlled.

Claims

1. A method for machining planar workpieces (10), in particular metal sheets, using a machine tool (1), - in which an upper tool (11) is positioned, using at least one motorized drive assembly (17), along an upper positioning axis (16) that runs perpendicular to a vertical axis (14), the upper tool being movable, using a vertical drive device (13), along said vertical axis (14) in the direction of a workpiece (10) to be machined using the upper tool (11) and in the opposite direction, - in which a lower tool (9) that is aligned with the upper tool (11) is positioned, using at least one motorized drive assembly (26), along a lower positioning axis (25) aligned perpendicular to the vertical axis (14) of the upper tool (11), - in which the upper and lower tools (11, 9) are moved inside the frame interior (7) of a machine frame (2), - in which the workpiece (10) lies on a workpiece support (28, 29) for machining, - in which a controller (15) is used to control the motorized drive assemblies (17, 26) for the purpose of moving the upper and lower tools (11, 9), and - in which at least one workpiece part (81) is cut from the workpiece (10), characterized in that - the displacement of the upper tool (11) along the upper positioning axis (16) and the displacement of the lower tool (9) along the lower positioning axis (25) are each controlled independently of one another, - in order to remove the at least one workpiece part (81) cut from the workpiece (10) after the last separating cut, the upper tool (11) is moved outside of a spatial volume (220) which extends above the cut workpiece part (81) and which is defined at least by a predefined part of the base area of the workpiece part (81) in the workpiece plane and part of a perpendicular to the workpiece part (81) extending in the direction of the upper positioning axis (16), or by a predefined part of the base area and of a region outside the base area of the workpiece part (81) in the workpiece plane and part of a perpendicular to the workpiece part (81) extending in the direction of the upper positioning axis (16), and - the cut workpiece part (81) is then removed.

2. The method according to claim 1, characterized in that the at least one workpiece part (81) is removed using at least one holding element (295) of a gripping device (292), the at least one holding element (295) being extended into the spatial volume (220) to remove the at least one workpiece part (81).

3. The method according to one of claims 1 or 2, characterized in that before a table segment (285) provided in the workpiece support (28, 29) is lowered so as to eject the at least one workpiece part (81) cut from the workpiece (10), the upper tool (11) is moved outside of the spatial volume (220).

4. The method according to claim 1, characterized in that the upper tool (11) is moved outside of the spatial volume (220) along the upper positioning axis (16).

5. The method according to claim 3, characterized in that after a last separating cut, or a cutting free, of a residual connection (82) of the workpiece part (81) to the workpiece (10), while lowering the table segment (285), the lower tool (9) is positioned at rest in the last working position for the separating cut, or the cutting free.

6. The method according to one of the preceding claims, characterized in that to eject the workpiece part (81) the table segment (285) is pivoted about an axis of rotation (286) and lowered, the axis of rotation being aligned parallel to the upper positioning axis (16) of the upper tool (11).

7. The method according to one of claims 3 to 6, characterized in that the spatial volume (220) is formed by a tilting region of a workpiece edge (289) of the workpiece part (81), the edge lying opposite to the direction of ejection (287), as the workpiece part is ejected along the table segment (285).

8. The method according to claim 7, characterized in that after the upper tool (11) is displaced outside the tilting region of the workpiece part (81), a length of the workpiece part (81) to be ejected, said length being within the length of the table segment (285), is exposed and is determined by a distance between the workpiece support (28, 29) and a disrupting edge of the machine frame (2) arranged above it.

9. A machine tool for machining planar workpieces (10), preferably metal sheets, - comprising an upper tool (11) which can be positioned, using at least one motorized drive assembly (17), along an upper positioning axis (16) that runs perpendicular to a vertical axis (14), the upper tool being movable, using a vertical drive device (13), along said vertical axis (14) in the direction of a workpiece (10) to be machined using the upper tool (11) and in the opposite direction, - comprising a lower tool (9) that is aligned with the upper tool (11) and can be positioned, using at least one motorized drive assembly (26), along a lower positioning axis (25) aligned perpendicular to the vertical axis (14) of the upper tool (11), - comprising a machine frame (2), inside the frame interior (7) of which the upper and lower tools (11, 9) can be moved, and - comprising a workpiece support (28, 29) on which the workpiece (10) lies in order to be machined, and - comprising a controller (15) by means of which the motorized drive assemblies (17, 26) can be controlled for the purpose of moving the upper and lower tools (11, 9), characterized in that - the displacement of the upper tool (11) along the upper positioning axis (16) and the displacement of the lower tool (9) along the lower positioning axis (25) can each be controlled independently of one another, and - in order to remove the at least one workpiece part (81) cut from the workpiece (10), the upper tool (11) is positioned outside of a spatial volume (220) which extends above the cut workpiece part (81) and which is defined at least by a predefined part of the base area of the workpiece part (81) in the workpiece plane and part of a perpendicular to the workpiece part (81) extending in the direction of the upper positioning axis (16), or by a predefined part of the base area and of a region outside the base area of the workpiece part (81) in the workpiece plane and part of a perpendicular to the workpiece part (81) extending in the direction of the upper positioning axis (16).

10. The machine tool according to claim 9, characterized in that a gripping device (292) comprising at least one holding element (295) is provided and that the at least one holding element (295) can be moved into the spatial volume (220) for the purpose of gripping and removing the at least one workpiece part (81).

11. The machine tool according to claim 10, characterized in that the gripping device (292) is arranged on a machine frame (2), preferably on an upper horizontal frame leg (3), and in particular that the gripping device can be moved, in particular using at least one linear axis (293, 294) of a linear drive (207), or that the gripping device (292) is provided with a linear drive (207) on a handling device which can be positioned adjacent to the workpiece support (28, 29).

12. The machine tool according to claim 9, characterized in that before a table segment (285) arranged in the workpiece support (28, 29) is lowered, the upper tool (11) can be controlled relative to the lower tool (9) by means of a displacement, and the upper tool (11) can be positioned outside the spatial volume (220) of the workpiece part (81) to be ejected.

13. The machine tool according to claim 12, characterized in that the table segment (285) is pivotably mounted along an axis of rotation (286) and the axis of rotation (286) is aligned parallel to the upper positioning axis (16) of the upper tool (11).