EP3515618B1 - Tool and machine tool and method for machining planar workpieces - Google Patents

Description

The invention relates to a tool and a machine tool and a method for processing plate-shaped workpieces, preferably sheet metal.

Such a machine tool is from the EP 2 527 058 B1 known. This document discloses a machine tool in the form of a press for machining workpieces, an upper tool being provided on a lifting device which can be moved in relation 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 stroke axis and opposite the upper tool, which is positioned on an underside. A stroke drive device for a stroke 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 with a motor drive. The lower tool is moved synchronously with a motor drive to the upper tool.

From the DE 200 18 936 U1 a machine tool for processing workpieces, in particular sheet metal, is known. This machine tool comprises a processing station, on which tool holders are provided for upper tool and lower tool that interact with one another and can be moved relative to one another while machining the workpiece. The upper and lower tools can be exchanged for different types of workpiece machining. For the bending processing of a plate-shaped workpiece, in particular a sheet metal, a bending tool is provided which comprises an upper tool and a lower tool, a pressure element with a bending edge being provided on the upper tool. The lower tool has a rotating body which interacts with the pressure body or the bending edge and which rotates parallel to the bending edge of the pressure body extending axis of rotation is rotatably received on the base body of the lower tool. This pressure body has an actuating leg and a pressure leg opposite the actuating leg on the axis of rotation of the rotating body, the rotating body being arranged in alignment with the bearing surface on the base body of the lower tool or set back in relation to the latter in the stroke direction when in a rest position. The lifting element acts on the actuating leg of the rotating body on the lower tool by means of a lifting movement of the upper tool relative to the lower tool or in the event of a relative movement of the upper tool relative to the lower tool. As a result, the latter is pivoted from a rest position about the axis of rotation into a working position, as a result of which the pivot arm swivels toward the pressure body of the upper tool while bending the workpiece. In this arrangement of the pressure body, it is provided that the bending edge is offset by the material thickness of the workpiece to be machined relative to the stroke axis of the upper tool. During a bending deformation of the workpiece, the relative movement of the upper tool and lower tool takes place in a common axis.

From the DE 93 07 907 U1 a folding machine is known which has a first tool on a lower beam and a second tool on an upper beam. A workpiece to be bent is clamped between the upper beam and the lower beam. After clamping, a further tool is subjected to a rotary movement on a bending cheek, as a result of which this bending cheek executes a rotational movement about a bending axis and introduces a bend into the workpiece.

The invention is based on the object of proposing a tool and a machine tool as well as a method for machining, in particular forming, plate-shaped workpieces, by means of which the flexibility in a length of a flap of workpieces to be bent is increased.

This task is accomplished by a tool for reshaping plate-shaped workpieces, in particular of sheet metal, solved with the features of claim 1.

The bending edge of a tool body arranged outside the projection surface of the base body makes it possible that the length of a flap to be bent on a workpiece or a flanged flap is no longer limited by a distance between a bending edge of the tool body and an underside of the base body of the upper tool, but rather rather, longer lengths of the tab or folding heights are made possible. The flexibility in the length of the folded tab is increased by the bending edge arranged eccentrically to the tool body, in particular outside the projection surface of the base body of the upper tool.

Furthermore, such an arrangement of the bending edge on a tool body off-center and outside the projection area of the base body of the upper tool has the advantage that multiple folding or multiple bending with longer tabs is made possible.

It is preferably provided that the projection surface is determined by a peripheral surface of the base body of the upper tool. The circumferential surface of the base body is quasi displaced along the position axis of the upper tool into the plane of the bending edge and the bending edge of the tool body is fixed tangentially adjacent or outside of this projection surface by the tool body. This peripheral surface of the base body is determined, inter alia, by a cassette in the magazine in which these tools are stored.

Furthermore, it is preferably provided that the tool body has a base surface adjacent to the bending edge and, opposite, an inclined surface adjacent to the bending edge. This enables the angle of the fold to be determined. The base surface is advantageously aligned parallel to the workpiece plane. The inclined surface is advantageously at an angle of less than the base surface Arranged 90 °. Alternatively, it can also be provided that this inclined surface has an angle of greater than 90 °, which then enables bevels which have an angle of greater than 90 ° with respect to the workpiece plane.

The tool body can merge directly into the base body by means of a connection surface, so that the base body and tool body are formed in one piece. Alternatively, the tool body and clamping pin can be formed in one piece and an adjusting ring can be provided as a clamping ring with the adjusting wedge arranged thereon. A one-piece upper tool can also be formed.

According to a preferred embodiment, it is provided that the position axis of the upper tool lies in the connection section of the tool body. Sufficient rigidity and power transmission can thereby be made possible despite the bending edge arranged off-center and at a distance from the position axis.

One embodiment of the upper tool provides that the tool body, on which the bending edge is provided, has a longitudinal axis which is inclined to the positioning axis. The inclination and / or length can also determine a length of the fold or tab to be produced.

The object on which the invention is based is further achieved by a machine tool in which an upper tool is provided which can be moved 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 and which runs along a axis perpendicular to the lifting axis Upper positioning axis is positionable and can be moved along the upper positioning axis with a motor drive arrangement. Furthermore, a lower tool is provided which is aligned with the upper tool and can be moved along a lower lifting axis with a lifting drive device in the direction of the upper tool and in the opposite direction and can be positioned along a lower positioning axis which is perpendicular to the lifting axis of the upper tool aligned and can be moved with a motor drive arrangement along the lower positioning axis. The machine tool has a control by means of which the motor drive arrangements for moving the upper and lower tools can be controlled. It is provided that the traversing movement of the upper tool along the upper positioning axis and the traversing movement of the lower tool along the lower positioning axis can each be controlled independently of one another and a tool according to one of the above-described embodiments is used. This enables the upper and / or lower tool to be moved independently and relative to one another along their positioning axes, so that depending on the material thickness of the workpiece to be machined, positioning of a bending edge of the tool body relative to the rotating body of the lower tool is made possible in a simple manner.

Furthermore, it is preferably provided that the upper tool and / or the lower tool can each be controlled independently of one another with a rotary movement and / or a movement along the position axes. This enables individual settings. This possibility for controlling the upper tool and / or lower tool can also achieve the advantage that, for example in the case of a multiple bend or multiple folding in the case of a multiple bend, which in turn is directed towards the upper tool, the bending edge by means of a movement and / or pivoting movement from the multiple bend can be brought out in order to then carry out a simple lifting movement, so that the upper and lower tools can be prepared again for the next working stroke.

The object on which the invention is based is further achieved by a method for machining plate-shaped workpieces, in which a tool according to one of the above-described embodiments is used and the upper tool and / or the lower tool are actuated at least with a lifting movement in which the position axes are parallel to one another be spaced. The independent traversing movement of the upper tool and / or lower tool along the upper positioning axis and lower positioning axis makes it possible to adjust the distance between the upper tool and the lower tool, taking into account the eccentric arrangement of the bending edge on the upper tool. The material thickness for the workpiece to be machined can also be taken into account in a simple manner.

It is preferably provided that a distance of the position axes between the lower tool and the upper tool is controlled in such a way that the center distance of the position axes results from the distance of the bending edge from the position axis on the base body of the upper tool and at least from a material thickness of the workpiece to be machined.

A further preferred embodiment of the method provides that a lifting movement is controlled between the upper tool and the lower tool, in which in a first lifting phase the upper tool is controlled along a lifting movement outside the lifting phase and shortly before the bending edge of the tool body rests on the workpiece or when lying on the workpiece, a second lifting phase is initiated along the lifting axis. This alternative embodiment makes it possible to move the upper tool to the lower tool deviating from a movement only along the lifting axis. This can be advantageous, for example, if a second or further bend or bend is to be made in the tab and it is no longer possible for the upper tool to approach the lower tool directly along the stroke axis.

• Figur 1 eine perspektivische Ansicht der erfindungsgemäßen Werkzeugmaschine,
• Figur 2 eine schematisierte Darstellung des grundsätzlichen Aufbaus einer Hubantriebsvorrichtung und eines motorischen Antriebes gemäß Figur 1,
• Figur 3 ein schematisches Diagramm einer überlagerten Hubbewegung in Y- und Z-Richtung des Stößels gemäß Figur 1,
• Figur 4 ein schematisches Diagramm einer weiteren überlagerten Hubbewegung in Y- und Z-Richtung des Stößels gemäß Figur 1,
• Figur 5 eine schematische Ansicht von oben auf die Werkzeugmaschine gemäß Figur 1 mit Werkstückauflageflächen,
• Figur 6 eine schematische Seitenansicht eines Werkzeuges, welches ein Oberwerkzeug und ein im Schnitt dargestelltes Unterwerkzeug umfasst,
• Figur 7 eine schematische Ansicht von oben auf das Oberwerkzeug,
• Figur 8 eine schematische Ansicht von oben auf das Unterwerkzeug,
• Figur 9 - 13 schematische Darstellung der Werkstückbearbeitung mit dem Werkzeug nach Figur 6,
• Figur 14 eine perspektivische Ansicht eines Werkstückes nach der Bearbeitung mit dem Werkzeug gemäß Figur 6,
• Figur 15 eine schematische Seitenansicht einer alternativen Ausführungsform des Oberwerkzeugs und
• Figur 16 eine schematische Seitenansicht eines alternativen Werkzeugs mit einem Werkstück mit einer Mehrfachabkantung.

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. The features to be gathered from the description and the drawings can be used according to the invention individually or in groups in any combination. Show it:

• Figure 1 2 shows a perspective view of the machine tool according to the invention,
• Figure 2 a schematic representation of the basic structure of a linear drive device and a motor drive according to Figure 1 ,
• Figure 3 a schematic diagram of a superimposed stroke movement in the Y and Z directions of the plunger Figure 1 ,
• Figure 4 a schematic diagram of a further superimposed stroke movement in the Y and Z directions of the ram Figure 1 ,
• Figure 5 a schematic view from above of the machine tool according to Figure 1 with workpiece contact surfaces,
• Figure 6 1 shows a schematic side view of a tool which comprises an upper tool and a lower tool shown in section,
• Figure 7 a schematic view from above of the upper tool,
• Figure 8 a schematic view from above of the lower tool,
• Figure 9-13 schematic representation of workpiece machining with the tool after Figure 6 ,
• Figure 14 a perspective view of a workpiece after machining with the tool according to Figure 6 ,
• Figure 15 is a schematic side view of an alternative embodiment of the upper tool and
• Figure 16 is a schematic side view of an alternative tool with a workpiece with a multiple fold.

In Figure 1 A machine tool 1 is shown, which is designed as a punch press. This machine tool 1 comprises a support 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 surrounds the working area of the machine tool 1 with an upper tool 11 and a lower tool 9 forms.

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

The upper tool 11 and lower tool 9 can also be used instead of a punch and a punch die as a bending punch and a bending die for forming workpieces 10.

The upper tool 11 is fixed in a tool holder at a lower end of a plunger 12. The plunger 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 stroke axis 14 runs in the direction of the Z axis of the coordinate system one in Figure 1 indicated numerical control 15 of the machine tool 1. Perpendicular to the stroke axis 14, the stroke 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 direction of the coordinate system of the numerical control 15. The lifting drive device 13 receiving the upper tool 11 is moved along the positioning axis 16 by means of a motor drive 17.

The movement of the plunger 12 along the stroke axis 14 and the positioning of the stroke drive device 13 along the positioning axis 16 take place 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 running in the direction of the positioning axis 16 and firmly connected to the machine frame 2 18. The lifting drive device 13 is guided during movements along the positioning axis 16 on three guide rails 19 of the upper frame leg 3, by those in Figure 1 two guide rails 19 can be seen. One remaining guide rail 19 runs parallel to the visible guide rail 19 and is spaced from it in the direction of the X axis of the coordinate system of the numerical 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 on the machine frame 2 via the guide shoes 20 and the guide rails 19. Another 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.

The lower tool 9 is movably received 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 on the lower positioning axis 16 with a motor drive arrangement 26 along the positioning axis 25. As an alternative or in addition, 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 stroke drive device 27 can correspond in structure to the upper stroke drive device 13. The motor drive arrangement 26 can also correspond to the motor drive arrangement 17.

The lower lifting drive device 27 is also slidably mounted on a lower horizontal frame leg 4 associated guide rails 19. 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 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 on the machine frame 2 via the guide shoes 20 and the guide rails 19 and at a distance from the guide rails 19 and guide shoes 20 of the upper lifting drive device 13. The lifting drive device 27 can also comprise a wedge gear 21, by means of which the position or height of the lower tool 9 can be adjusted along the Z axis.

The numerical control 15 can be used to independently control both the motor drives 17 for a movement of the upper tool 11 along the upper positioning axis 16 and the motor drive or motors 26 for a movement of the lower tool 9 along the lower positioning axis 25. The upper and lower tools 11, 9 can thus be moved synchronously in the direction of the Y axis of the coordinate system. Likewise, an 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 tool 11, 9 can be controlled at the same time. 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 various ways for machining the workpieces 10.

A component of the lifting drive device 13 is the wedge gear 21, which in Figure 2 is shown. The wedge gear 21 comprises two wedge gear elements 122, 123 on the drive side and two wedge gear elements 124, 125 on the output side. The latter are structurally combined to form a structural unit in the form of a double wedge 126 on the output side. The tappet 12 is rotatably mounted on the output-side double wedge 126 about the lifting axis 14. A motor-driven rotary drive device 128 is accommodated in the output-side double wedge 126 and, if necessary, moves the tappet 12 along the Lift axis 14. Both left and right rotation of the tappet 12 according to the double arrow in Figure 2 possible. A plunger bearing 129 is shown schematically. On the one hand, the tappet bearing 129 allows low-friction rotary movements of the tappet 12 about the lifting axis 14, on the other hand the tappet bearing 129 supports the tappet 12 in the axial direction and accordingly carries loads which act on the tappet 12 in the direction of the lifting axis 14 into the output-side double wedge 126 from.

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. The wedge surfaces 130, 131 of the output-side wedge gear elements 124, 125 lie opposite wedge surfaces 132, 133 of the drive-side wedge gear elements 122, 123. Longitudinal guides 134, 135 guide the wedge gear element 122 on the drive side and the wedge gear element 124 on the output side, as well as the wedge gear element 123 on the drive side and the wedge gear element 125 on the output side in the direction of the Y axis, that is to say in the direction of the positioning axis 16 of the linear drive device 13, so as to be movable relative to one another.

The drive-side wedge gear element 122 has a motor drive unit 138, 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.

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

For the motor drive units 138, 139, the drive-side wedge gear elements 122, 123 are operated in such a way that they move along the positioning axis 16, for example, which results 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 hand . As a result of this relative movement, the output-side double wedge 126 and the plunger 12 mounted thereon moves downward along the stroke axis 14. The punch, which is mounted on the plunger 12, for example as the upper tool 11, performs a working stroke and thereby processes a workpiece 10 mounted on the workpiece support 28, 29 or the workpiece support 8. The plunger 12 is in turn moved along the side by an opposite movement of the drive wedge elements 122, 123 Lift axis 14 raised or moved up.

The above-described linear drive device 13 according to Figure 2 is preferably constructed identically as a lower lifting drive device 27 and receives the lower tool 9.

In Figure 3 a schematic diagram of a possible stroke movement of the plunger 12 is shown. The diagram shows a stroke along the Y axis and the Z axis. By superimposing a movement of the plunger 12 along the stroke axis 14 and along the positioning axis 16, for example, an obliquely extending stroke movement of the stroke plunger 12 can be driven downward towards the workpiece 10, as is represented by the first straight line A. Subsequently, after the stroke has been carried out, the plunger 12 can, for example, be lifted vertically, as represented by the straight line B. This is followed, for example, by an exclusive movement along the Y axis along the straight line C in order to position the ram 12 for a new working position relative to the workpiece 10. The work sequence described above 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 movement along the straight line C can also be omitted.

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

This exemplary superimposed stroke profile can be controlled both for the upper tool 11 and the lower tool 9. Depending on the machining of the workpiece 10 to be carried out, a superimposed lifting movement of the upper tool and / or lower tool 11, 9 can be controlled.

In Figure 4 a schematic diagram is shown, which represents a lifting movement of the plunger 12 according to the exemplified line D along a Y-axis and a Z-axis. Deviating from Figure 3 In this exemplary embodiment it is provided that a stroke movement of the tappet 12 can run through a curve or an arc, in that an overlay of the movement movements in the Y direction and Z direction is controlled accordingly by the controller 15. Such flexible superimposition of the traversing movements in the X and Z directions enables specific machining tasks to be solved. The control of such a curve course can be provided for the upper tool 11 and / or lower tool 9.

In Figure 5 12 is a schematic view of the machine tool 1 according to FIG Figure 1 shown. A workpiece support 28, 29 extends laterally on the machine frame 2 of the machine tool 1. The workpiece support 28 can be assigned, for example, to a loading station (not shown in more detail), through which unworked workpieces 10 are placed on the workpiece support surface 28. Adjacent to the workpiece support surface 28, 29 is a feed device 22 which comprises a plurality of grippers 23 in order to grip the workpiece 10 placed on the workpiece support 28. The workpiece 10 is guided through the machine frame 2 in the X direction by means of the feed device 22. The feed device 22 can preferably also be driven so as to be movable in the Y direction. A free movement of the workpiece 10 in the XY plane can thereby be provided. Depending on the work task, the workpiece 10 can be movable by the feed device 22 both in the X direction and counter to the X direction. This Movement movement of the workpiece 10 can be adapted to a movement movement of the upper tool 11 and lower tool 9 in and against the Y direction for the respective machining task.

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

The machine tool 1 can furthermore have a laser processing device 201, in particular a laser cutting machine, which is only schematically shown in a plan view in FIG Figure 5 is shown. This laser processing device 201 can be designed, for example, as a CO ₂ laser cutting machine. The laser processing device 201 comprises a laser source 202, which generates a laser beam 203, which is guided and focused in a laser processing head, in particular laser cutting head 206, by means of a schematically illustrated beam guide 204. Thereafter, the laser beam 204 is aligned perpendicular to the surface of the workpiece 10 by a cutting nozzle in order to machine the workpiece 10. The laser beam 203 acts on the workpiece 10 at the machining location, in particular the cutting location, preferably together with a process gas jet. The cutting point at which the laser beam 203 strikes the workpiece 10 is adjacent to the processing point of the upper tool 11 and lower tool 9.

The laser cutting head 206 can be moved by a linear drive 207 with a linear axis system at least in the Y direction, preferably in the Y and Z direction. This linear axis system, which receives 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 space of the laser cutting head 206. A can preferably be located below the beam passage opening Beam collecting device for the laser beam 21 may be provided. The beam passage opening and optionally the beam collecting device can also be designed as a structural unit.

As an alternative, the laser processing device 201 can also have a solid-state laser as the laser source 202, the radiation of which is guided to the laser cutting head 206 with the aid of an optical fiber cable.

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

For example, a machined workpiece 10 rests on the workpiece support 28, in which a workpiece part 81 is cut free from a cutting gap 83, for example by punching machining or by laser beam machining, except for a residual connection 82. The workpiece 81 is held in the workpiece 10 or the remaining residual grid by this residual connection. 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 discharging step. The remaining connection 82 is separated by a punch stroke of the upper tool 11 to the lower tool 9. The workpiece part 81 can be removed, for example, by partially lowering the workpiece support 8 downwards. Alternatively, in the case of larger workpiece parts 81, the cut-away workpiece part 81 can be transferred back to the workpiece support 28 or to the workpiece support 29 in order to unload the workpiece part 81 and the scrap skeleton. Small workpiece parts 81 can optionally also be discharged through an opening in the lower tool 9.

In Figure 6 a tool 31 is shown as a turning / bending tool. This tool 31 comprises an upper tool 11 and a lower tool 9. The upper tool 11 comprises a base body 33, on which a clamping shank 34 is arranged. This can be one Position axis 35 can be rotatably arranged in a tool holder of the machine tool 1. Furthermore, an indexing wedge 36 can be provided on the base body 33 in order to align a tool body 39 provided on the base body 33. The tool body 39 is provided on the base body 33 opposite the clamping shaft 34. At the free outer end, this comprises a bending edge 38, from which a base surface 43 and an inclined surface 44 can extend in the direction of the base body 33. The tool body 39 comprises a longitudinal axis 40. This longitudinal axis 40 can be inclined with respect to the position axis 35.

The lower tool 9, which in Figure 8 Shown in a plan view comprises a base body 41 on which an indexing element (not shown in more detail) for aligning the upper tool 11 in a tool holder of the machine tool 1 can be provided. The base body 41 receives a bearing block 51 on which a partially cylindrical square bolt 52 is rotatably mounted in a corresponding recess 53 about an axis of rotation 54. The axis of rotation 54 of the edge bolt 52 extends parallel to the bending edge 38. The edge of the recess 53 is for effective rotation of the edge bolt 52 in Figure 6 provided on its right side with an inflated part 55. The bearing block rests on the base of the pot-shaped base body 41 of the lower tool 9. Pins 56 are used to position it relative to the base body 41, fixing screws 57 for fixing it to the base body 41. A return spring 58 is supported on one side of the bearing block 51 and is attached to it Free end acts on the square bolt 52 with a radial distance from its axis of rotation 54.

A support surface 47 is provided on the base body 41 of the lower tool 9, which is movably supported on the base body 41 along a position axis 48 of the base body 41, which also forms a longitudinal axis. A spring element 59 is used to support the workpiece support 47, for example in the form of an annular rubber buffer or of spiral springs or the like. This is a Cover part 61, which comprises the workpiece support 47, with an edge pointing downward on the cover part 61 relative to an upward pointing edge of the base body 41 to the base body 41 movable up and down. An opening or recess 46 is provided on the support surface 47, within which the square bolt 52 is arranged. The square bolt 52 has a groove running in the direction of its axis of rotation 54, the longitudinal walls of which are formed by an actuating leg 65 and a pressure leg 66 opposite the actuating leg 65 on the axis of rotation 53. The opening angle of the groove 63 is, for example, 84.5 ° with a workpiece thickness of 1 mm and 1.5 mm and 80 ° with a workpiece thickness of 2 mm. A run-up slope 67 can form the transition between the support surface 47 and the edge of the cover part 61. In the cover part 61, opening longitudinal edges 68 are rounded and preferably polished.

In addition, a lubricating nipple 69 is also provided on the base body 51, which can introduce the introduction of lubricant into the area of the partially cylindrical contact surfaces between the bearing block 51 and the square bolt 52 rotatably mounted thereon.

In Figure 7 12 is a schematic top view of the upper tool 11 according to FIG Figure 6 shown. From this view as well as from the side view according to Figure 6 it can be seen that the bending edge 38 of the tool body 39 is arranged eccentrically to the position axis 35. It is preferably provided that this bending edge 38 is arranged outside a peripheral surface 71 of the base body 33. This peripheral surface 71 forms an outer circumferential outer surface of the cylindrically shaped base body 33. The bending edge 38 is preferably arranged outside a projection surface P of the base body 33. This projection surface P of the base body 33 results from a view along the position axis 35 onto the base body 33. In deviation from the peripheral surface 71, the projection surface P can be viewed, for example, as a circular surface which corresponds to the maximum outer circumference of the base body 33.

The bending edge 38 can be tangential to the projection surface P or can be provided outside the projection surface P.

To machine the plate-shaped workpiece 10, the position axis 35 of the upper tool 11 is aligned or moved with respect to the position axis 48 of the lower tool 9 such that a distance is formed between the position axis 35 and the position axis 48, which distance is formed, for example, from a distance A and the material thickness S. of the workpiece 10 to be machined. The distance A corresponds to the eccentric arrangement of the bending edge 38 to the position axis 35 on the upper tool 11. This positioning of the upper tool 11 to the lower tool 9 can be achieved by moving the upper tool 11 and / or the lower tool 9 relative to one another along, for example, the lower positioning axis 25 and / or upper positioning axis 16 of the machine tool 1. The upper tool 11 is aligned with respect to its orientation of the tool body 39 with its bending edge 38 on the groove 63 on the square bolt 52.

In the Figures 9 to 13 Individual work steps are shown that a bending deformation of a bend or tab 62 ( Figure 13 ) on the workpiece part 81 to the workpiece 10, so that the folded tab 62 or an upstand is formed. The workpiece 10 is controlled by the feed device 22 via the controller 15. The workpiece 10 is moved in and against the X-axis and is positioned in a machining position between the upper tool 11 and the lower tool 9, in which a partially cut-out workpiece part 81 or a cut-out tab 83 in a position axis 40 or stroke axis 30 of the lower tool 9 above the Edge bolt 52 is arranged. Such a position of the tool 31 is shown, for example, in a first side view in FIG Figure 9 and another view in Figure 10 shown. This alignment in Figure 10 also corresponds to that in Figure 6 . The upper tool 11 and lower tool 9 are moved along the Y axis and / or rotated about their position axis 35, 48 so that they correspond to the desired course of the bending line of the bevel 62 to be created are aligned. The workpiece part 81 to be bent covers the window-like recess or opening 46 of the support surface 47. The area of the workpiece 10 surrounding the workpiece part 81 lies on the support surface 47. After assuming a desired position of the workpiece 10 with the relevant workpiece part 81, the upper tool 11 is, for example, lowered onto the lower tool 9 along the stroke axis 14 or the position axis 35. The base surface 43 of the tool body 39 runs onto the workpiece 10 and holds it in between ( Figure 11 ). When the upper tool 11 is further lowered in the direction of the lower tool 9, the support surface 47 moves against a restoring force of at least one spring element 59 in the direction of the base body 41 of the lower tool 9. The lower tool 9 can also be raised in the direction of the upper tool 11. A common traversing movement towards one another can also be controlled. The workpiece 10 is pressed with the underside of the tab 62 against the actuating leg 65 of the square bolt 52, which is initially still in the rest position. When the distance between the upper tool 11 and the lower tool 9 is further reduced, the square bolt 52 is rotated about its axis of rotation 53 against the force of the return spring 58 and pivots with its pressure leg 66 through the window-like opening 46 and over the contact surface 47 in the direction of the Tool body 39. This causes the flap 62 to be bent, as from, via the pressure leg 66 of the square bolt 52 Figure 12 emerges. The rotary movement of the square bolt 52 and thus also the bending of the workpiece part 81 ends as soon as the upper tool 11 or its tool body 39 is in Figure 12 has shown the final position. The working stroke of the upper tool 11 is thus ended. The folded tab 62 on the workpiece part 81 encloses with the remaining workpiece 10 an angle corresponding to the opening angle of the groove 63 on the square bolt 52 of, for example, 88 ° and is accordingly opposite to that slightly bend the desired bending angle β of 90 °. Other bending angles or bending angles β can also be generated in this way.

The upper tool 11 is lifted along the lifting axis 14. In addition, this movement can be superimposed directly or delayed with a movement along the upper positioning axis 16. After the relief of the workpiece 10 by the tool body 39, the support 47 returns to an initial position. Likewise, the square bolt 52 is returned to an initial position. As a result, the folded tab 62 on the workpiece part 81 can also spring back into its position and, for example, assume a desired angle of 90 °, as shown, for example, in FIG Figure 14 is shown.

Due to the bending edge 38 of the upper tool 11 lying outside the projection surface P, a length of the tab 62 can be folded that is greater than a distance between an underside of the base body 33 of the upper tool 11 and the bending edge 38 spaced apart from it. This will increase the flexibility in the processing for folding tabs 62.

Due to the movable control of the upper tool 11 and / or the lower tool 9 along the upper positioning axis 16 and / or the lower positioning axis 25, pulls located on the tab 62 can also be processed without problems. Immediately after the tool body 39 of the upper tool 11 has been lifted off the workpiece 10, a movement along the upper and / or lower positioning axis 16, 25 of the upper tool 11 and lower tool 9 can be initiated, so that after a further lifting movement of the upper tool 11, the bending edge 38 is free of interference can be led past the passage. Alternatively or in addition, the feed control 22 can also move the workpiece 10 accordingly.

In Figure 15 12 is a schematic side view of an alternative embodiment of the upper tool 11 Figure 6 shown. In this embodiment, it is provided that the tool body 39 has a longitudinal axis 40 which lies in the position axis 35. This Tool body 39 can, for example, have a rectangular shape, a side surface being inclined laterally outwards with respect to base body 33 in order to form a bending edge 38 outside a projection surface of base body 33. In this embodiment, the base surface 43 can be aligned parallel to the workpiece plane or perpendicular to the position axis 35. Alternatively, this can also be inclined in the direction of the base body 33.

In Figure 15 Furthermore, a second embodiment of the upper tool 11 is shown schematically as an alternative in dashed lines. The dashed line also merges into the base surface 43 and ends with a bending edge 99 in the position axis 35. The tool body 39 thus has a bending edge 99 lying in the position axis 35 and also a bending edge 38 lying outside the base body 33. Thus, an upper tool 11 can be created, in which on the one hand short tabs or bevels 62 can be produced, the distance of which is determined from the bending edge lying within the projection surface P to an underside of the base body 33 and also longer bevels 62 are formed, namely due to the bending edge 38 arranged outside the base body 33. The bending edge 99 can also be located off-center or outside the position axis 35, however, within the projection surface P.

In Figure 16 12 is a schematic side view of an alternative embodiment of the upper tool 11 Figure 6 shown. In this upper tool 11 it is provided that the tool body 39 has a base surface 43 which extends along the workpiece plane, so that a bearing surface is created which extends from the position axis 35 to the bending edge 38 or even from a side opposite the bending edge 38 the position axis 35 extends to the bending edge 38. The tool body 39 has an L-shaped contour. Such a contour of the tool body 39 has the advantage that a multiple fold 62, 64 can be introduced on the workpiece 10.

First, a bending process for the first fold 62 is carried out, like this in the Figures 9 to 13 is described. The workpiece 10 is then moved so that it is brought into the position relative to the edge bolt 52 for the subsequent bend 64. Subsequently, the upper tool 11 can be moved by a vertical lifting movement along the lifting axis 14 to the square bolt 52 in order to form a further bevel 64. Since the bending edge 38 of the tool body 39 has already passed the first bend 62 before the bending edge 38 rests on the workpiece 10 and produces the subsequent bend 64, there is no collision with the first bend 62. Alternatively, the upper tool 11 can become the lower tool 9 can also be delivered by an inclined lifting movement or starting movement. After the base surface 43 rests on the workpiece 10, the further folding process takes place in analogy to the ones described above Figures 10 and 12 for the second fold 64 or further fold.

Since in this example of a double fold with an angle of 90 ° each, vertical lifting of the upper tool 11 relative to the lower tool 9 is not possible due to a collision with the workpiece 10, in particular the first fold 62, the following strategies can be used. A first control of the upper tool 11 is that it is now raised slightly along the stroke axis 14 in order to avoid scratching the surface of the workpiece 10 in a further movement. Subsequently or without a previous brief lifting movement, the upper tool 11 is guided out of the multiple bend along the upper positioning axis 16 until the bending edge 38 is exposed relative to a free end 98 of the first bend 62, in order to subsequently carry out a lifting movement along the lifting axis 14. Alternatively, it can be provided that the upper tool is initially moved slightly along the upper positioning axis 16 in order to then control a rotary movement about the position axis 35, so that the bending edge 28 can be pivoted out of the multiple fold 62, 64. This can be followed by a further movement of the upper tool 11 can be controlled for the subsequent machining process.

Claims (10)

1. A tool for machining planar workpieces (10), in particular metal sheets, comprising an upper tool (11) and comprising a lower tool (9), which are movable towards each another and in the opposite direction in a stroke direction for machining the workpiece (10) arranged therebetween, and the upper tool (11) comprises a clamping shaft (34) and a main body (33), which lie in a common positioning axis (35) and comprising a tool body (39) arranged opposite to the clamping shaft (34) on the main body (33), the tool body comprising a bending edge (38) and the lower tool (9) comprising a main body (41) which receives a rotational body (52) which is rotatable around an axis of rotation (54) running in a direction of the bending edge (38) of the tool body (39), characterized in that the main body (33) of the upper tool (11) forms a projection surface (P) perpendicular to the positioning axis (35) and seen in the stroke direction and the bending edge (38) of the tool body (39) is adjacent tangentially to the projection surface (P) or is provided outside the projection surface (P).
2. The tool according to claim 1, characterized in that the projection surface (P) is determined by a circumferential surface (71) of the main body (33) of the upper tool (11).
3. The tool according to claim 1 or 2, characterized in that the tool body (39) has a base surface (43) adjacent to the bending edge (38) and an inclined surface (44) adjacent to the bending edge (38), opposite to the bending edge (38) and the tool body (39) has a surface section (50) opposite the bending edge (38), which section passes over into the main body (33) or is fastenable on the main body (33).
4. The tool according to claim 3, characterized in that the positioning axis (35) lies in the connection section (50) of the tool body (39).
5. The tool according to one of the preceding claims, characterized in that a longitudinal axis (40) of the tool body (39) is inclined relative to the positioning axis (35) on the upper tool (11).
6. A machine tool for machining planar workpieces, preferably metal sheets,

   - comprising an upper tool (11) which is movable along a stroke axis (14) by means of a stroke drive device (13) in the direction of a workpiece (10) to be machined with the upper tool (11) and in the opposite direction and which is positionable along an upper positioning axis (16) which is oriented perpendicular to the stroke axis (14) and is movable by means of a motor drive device (17) along the upper positioning axis (16),

   - comprising a lower tool (9) which is oriented with the upper tool (11) and which is movable along a lower stroke axis (30) by means of a stroke drive device (27) in the direction of the upper tool (11) and in the opposite direction and is positionable along a lower positioning axis (25), which is oriented perpendicular to the stroke axis (14) of the upper tool (11) and is movable by means of a motor drive device (26) along the lower positioning axis (25),

   - comprising a controller (15), by means of which the motor drive devices (17, 26) is controllable for traversing the upper and lower tool (11, 9),
   characterized in that,

   - the traversing movement of the upper tool (11) along the upper positioning axis (16) and the traversing movement of the lower tool (9) along the lower positioning axis (25) are each independently controllable, and

   - a tool according to one of claims 1 to 5 is provided for machining workpieces (10).
7. The machine tool according to claim 6, characterized in that the upper tool (11) and/or lower tool (9) are each independently controllable by means of a stroke movement and/or a rotational movement about the positioning axis (35, 48).
8. A method for machining planar workpieces, preferably metal sheets,

   - in which an upper tool (11) which is movable along a stroke axis (14) by means of a stroke drive device (13) in the direction of a workpiece (10) to be machined with the upper tool (11) and in the opposite direction and which is positionable along an upper positioning axis (16) which is oriented perpendicular to the stroke axis (14), is moved by means of a motor drive device (17) along the upper positioning axis (16),

   - in which a lower tool (9), which is oriented with the upper tool (11) and is positionable along a lower positioning axis (25), which is oriented perpendicular to the stroke axis (14) of the upper tool (11), is moved by means of a motor drive device (26) along the lower positioning axis (25),

   - in which the drive arrangements (17, 26) for moving the upper and lower tool (11, 9) are controlled by a controller (15), characterized in that,

   - a tool (31) according to one of claims 1 to 5 is used for machining the workpieces (10), and

   - the upper tool (11) and/or the lower tool (9) are controlled at least by means of a stroke movement in which the position axes (35, 48) are spaced parallel to each another.
9. The method according to claim 8, characterized in that a distance of the position axes (35, 48) between the lower tool (9) and the upper tool (11) is controlled, which results from the distance of the bending edge (38) to the positioning axis (35) on the main body (33) of the upper tool (11) and at least of a material thickness (S) of the workpiece to be machined (10).
10. The method according to claim 8 or 9, characterized in that a stroke movement is controlled between the upper tool (11) and the lower tool (9), in which movement, in a first stroke phase, the upper tool (11) is controlled along a stroke movement outside the stroke axis (14), and shortly before the bending edge (38) of the tool body (39) rests on the workpiece (10) or when resting on the workpiece (10), a second stroke phase is introduced along the stroke axes (14, 30).

Images