GRIPPING DEVICE FOR A HANDLING DEVICE OF A MACHINING MACHINE

Description

[0001] The invention relates to a gripping device for a handling device of a processing machine, in particular for processing plate-shaped workpieces.

[0002] From JP 5 853 373 B1, a gripping device for a handling system is known. This gripping device comprises a base body with several vacuum suction cups and a sealing element that surrounds the vacuum suction cups. To handle a plate-shaped workpiece, the vacuum suction cups are simultaneously pressurized with negative pressure by a pump and the sealing element by a fan.

[0003] From JP 2004 203 532 A1, a gripping device for handling a plate-shaped material is known. This gripping device comprises a carrier plate made of a porous material, which includes a plurality of through-holes. A rollable seal is provided around the outside of the carrier plate. This allows the rollable seal to bear against uneven objects when handling them, creating a vacuum between the object being handled, the surrounding seal, and the porous carrier plate.

[0004] From JP H03 142 187 A, a gripping device is known which comprises two nested vacuum suction cups. The nested vacuum suction cups are movable relative to each other in height, so that either the vacuum suction cup with a larger gripping surface or the vacuum suction cup with a smaller gripping surface grips an object of corresponding size.

[0005] From EP 1 967 301 A1, a machine arrangement for processing plate-shaped workpieces is known, comprising a processing unit and a handling device for the processed products. This machine is used for processing plate-shaped workpieces, particularly sheet metal. Preferably, punching and / or cutting operations are performed. For handling the workpieces, the handling device includes a gripping device. This gripping device has one or more suction plates, each with a plurality of vacuum suction cups. To grip the workpieces, the vacuum suction cups are brought into contact with the workpiece. Subsequently, a vacuum is applied, causing the workpiece to be gripped by the vacuum suction cups. The workpieces can then be handled. Each of these vacuum suction cups consists of a suction element that engages the workpiece and a valve for controlling the vacuum suction.

[0006] From DE 10 2014 215 102 A1, a surface suction gripper for picking up and handling workpieces is known. These surface suction grippers comprise a closed housing with a permanently integrated gripping plate, on which several suction openings are provided. Within the housing, closure elements, each with a sealing section, are provided. This sealing section can connect one or more suction openings to the closure element and apply a vacuum to these suction openings according to the number of surrounding suction openings. This allows several groups of suction openings within a gripping plate to be controlled.

[0007] The invention is based on the objective of proposing a gripping device for a handling device of a processing machine, which enables an adjustment in the holding force for the transport of plate-shaped workpieces.

[0008] This task is solved by a gripping device for a handling device, which comprises several vacuum suction cups on a base body, which are arranged to each other in at least one suction field and which can be controlled with negative pressure for handling the workpieces, wherein at least one holding device is provided on the base body, which has at least one sealing element and surrounds at least one suction field, and which has a control device for applying a further negative pressure to the at least one sealing element for the plate-shaped workpiece.This arrangement offers the advantage that, under high forces, such as when loading or transporting an unmachined, flat workpiece, the gripping device can be subjected to an additional holding force beyond the vacuum suction cups of at least one suction cup array. This additional holding force is generated by the at least one sealing element of the gripping device, which surrounds the at least one suction cup array. Thus, the holding force can be increased by an area subjected to negative pressure, which is limited by the sealing element. The sealing element surrounds the at least one suction cup array, allowing the additional force to be generated over a larger area than that of the suction cup array itself. Furthermore, this arrangement allows the individual vacuum suction cups and / or suction cup arrays of the gripping device to be optimally positioned on the flat workpiece, depending on its geometry.

[0009] Preferably, a sealing element surrounds all suction cups provided on the base body. This allows for a simple design to increase the holding force. The arrangement and design of the suction cups of a known gripping element and their control can be retained.

[0010] Alternatively, an externally circumferential sealing element can be provided for each suction cup field or at least a group of suction cup fields. This allows for individualized and increased control of the holding force for each suction cup field.

[0011] Furthermore, the control unit of the holding device includes at least one valve for applying a vacuum, which is separate from the at least one valve for controlling the vacuum suction cups in the suction field. This enables the holding device to be controlled on demand while maintaining the gripping function of the gripping device.

[0012] Another preferred embodiment of the control device provides that at least one valve of the control device is located in or associated with the suction cup array. This allows for a compact design of the gripping device. Preferably, the valve of the control device can be integrated at the position of a vacuum suction cup within a suction cup array.

[0013] At least one sealing element of the holding device can be moved up and down relative to one of the gripping planes formed by the vacuum suction cups. This arrangement has the advantage that, when not in use, at least one sealing element is raised above the gripping plane of the vacuum suction cups. This can result in reduced wear of at least one sealing element.

[0014] Preferably, at least one sealing element of the holding device is actuated vertically on the base body by a drive mechanism, wherein the sealing element is arranged in a starting position above the gripping plane formed by the vacuum suction cups. The drive allows the sealing element to be moved into a gripping position that lies within the gripping plane of the vacuum suction cups or protrudes from the gripping plane of the vacuum suction cups. This arrangement and design enables the at least one sealing element to securely contact and grip the plate-shaped workpiece to be handled, thus generating an additional holding force. Individual suction cup arrays can also be moved from a non-use position to a gripping position with their respective vacuum suction cups. This individual actuation of the vacuum suction cups and / or suction cup arrays also allows for the gripping of formed plate-shaped workpieces.

[0015] Advantageously, after placing at least one suction cup of the gripping device on the flat workpiece to be handled, at least one sealing element can be moved into a gripping position, whereby the vacuum suction cups of the at least one suction cup and the at least one sealing element can be successively pressurized with negative pressure. Alternatively, the vacuum suction cups of the at least one suction cup and the at least one sealing element placed on the flat workpiece can also be pressurized with negative pressure simultaneously. In the latter case, a shorter process cycle can be achieved.

[0016] According to a preferred embodiment of the gripping device, the drive for the at least one sealing element movable up and down is designed, for example, as a reciprocating piston drive, in particular a pneumatic cylinder, as a linear drive, as an electric motor, or as an electromagnetic drive. Preferably, at least two reciprocating piston drives are provided, which engage on one side with the base body and on the other side with a holding frame that accommodates the sealing element, in order to control an up and down movement of the sealing element.

[0017] The at least one sealing element of the holding device is preferably designed as a circumferential sealing lip. According to a first embodiment, this sealing lip can be made of a thermoplastic elastomer. It is also possible for such a sealing lip to be made of a foam. In particular, the foam design allows for easy adaptation of the sealing element's geometry to the structural contours of the base body.

[0018] The invention, as well as 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 that can be derived from the description and the drawings can be applied individually or in any combination according to the invention. The drawings show: Figure 1a perspective view of a processing machine and a handling device with a gripping device having a vacuum suction cup according to the prior art, Figure 2 a schematic view from below of a suction plate of the gripping device in Figure 1 according to the state of the art, Figure 3 a perspective view of a gripping device, Figure 4 a schematic view from below of the gripping device according to Figure 3 , Figure 5 a schematic side view of the gripping device according to Figure 3 with an additional holding device in a starting position, Figure 6 a schematic sectional view of the gripping device according to Figure 5 with the holding device in a gripping position, Figure 7 a schematic view of the gripping device according to Figure 6 in another configuration in a gripping position, Figure 8a schematic view from below of an alternative embodiment of the gripping device according to Figure 3 , Figure 9 a perspective view of a gripping device with multiple gripping elements according to Figure 3 , Figure 10 a perspective view of an alternative embodiment of the gripping device according to Figure 9 with multiple gripping devices according to Figure 3 .

[0019] In Figure 1A machining center 11, for example a punching machine, is shown in perspective. For machining a plate-shaped workpiece 12, for example a sheet metal part, a preferably stationary machining unit 21 with a punching head 14 and a punching die (not shown in detail) is provided. Alternatively, a laser punching machine can be used, in which a laser processing head is provided adjacent to the punching head 14. The workpiece 12 to be machined rests on a workpiece support 16 during machining. The workpiece 12 is held during machining by a holding device 17, which preferably includes clamps 18, and can be moved relative to the punching head 14 in the X-direction of the workpiece plane (X / Y plane) by means of a conventional linear drive 19, indicated by an arrow.In the Y-direction of the workpiece plane, the workpiece 12 can be moved by means of a conventional linear drive 20 (indicated by an arrow) by moving the workpiece support 16 together with the holding device 17 relative to a base 24 on which the workpiece support 16 is mounted. In this way, the workpiece 12 can be moved in the X- and Y-directions relative to the punching head 14, so that the area of ​​the workpiece 12 to be processed can be positioned within the processing area of ​​the punching head 14. The processing area lies between the punching head 14 and a replaceable punching die (not shown). Similarly, a laser optic can be arranged in the stationary processing area of ​​the laser processing head in a laser punching machine.

[0020] A handling device 26 is provided on one end face of the workpiece support 16 of the processing machine 11, which also includes a gripping device 27 that can be moved along at least one linear axis 25 from a loading and unloading position 22, 23 for the plate-shaped material 12 to a removal position or waiting position in order to pick up a machined workpiece 36 and, for example, remove it from the processing machine 11 or place it in a magazine 50.

[0021] The processing machine 11 can alternatively also be designed as a laser processing machine or a laser punching processing machine, which instead of an open base body has a closed base body, in particular a circumferential frame, which preferably extends in the Y direction.

[0022] In Figure 2Figure 1 shows a perspective view from below of a gripping device 27 according to the prior art. This gripping device 27 comprises a base body 33, which, for example, includes three suction cup fields 39, within which one or more suction elements 31 are provided. In the illustrated embodiment, for example, five vacuum suction cups 35 are arranged one another in a suction cup field 39. These vacuum suction cups 35 are jointly actuated by a valve (not shown) with a vacuum to generate a holding force on a plate-shaped workpiece 12.

[0023] In Figure 3 Figure 1 shows a perspective view of a gripping device 27 according to the invention. Figure 4 shows a schematic view from below of the gripping device according to Figure 3 . In Figure 5 is a schematic sectional view of the gripping device 27 according to Figure 3 depicted.

[0024] The gripping device 27 comprises the base body 33, which has, for example, fastening elements and / or fastening sections 34 on its upper side, in order to attach the gripping device 27 to a gripping frame 28 or a gripping device 29 ( Figure 8 and 9 ) to fix. From the view according to Figure 4 It is evident that this gripping device 27 comprises, for example, eight suction cup fields 39, with each suction cup field 39 being assigned, for example, four vacuum suction cups 35.

[0025] A holding device 41 is provided on the gripping device 27, which comprises a sealing element 42 and a control device 47. This control device 47 consists of at least one actuator 53 and at least one valve 48, via which a vacuum for the sealing element 42 can be controlled. This valve 48 is controlled by a control unit (not shown in detail). This control unit (not shown in detail) can also control the vacuum suction cups 35 of the suction cup array 39.

[0026] The sealing element 42 is shown in the illustrated embodiment as an externally circumferential sealing element 42 which surrounds all suction fields 39 of the gripping device 27.

[0027] The circumferential sealing element 42 is received by a retaining frame 43. This retaining frame 43 is guided so that it can move up and down relative to the base body 33. To control this up and down movement, the control device 47 has a drive 53, which is fixedly mounted at one end to the base body 33 and engages the retaining frame 43 at the opposite end. Preferably, this drive 53 is designed as a reciprocating piston drive. Advantageously, several pneumatic reciprocating cylinders are used to control a uniform up and down movement of the sealing element 42. The drive 53 is preferably controlled by the control unit (not shown in detail) and is coordinated with the operation of the at least one valve for the sealing element 42 and the valves for controlling the vacuum suction cups 35.

[0028] This circumferential sealing element 42 is designed according to Figure 5 shown in the starting position 44. The vacuum suction cups 35 are located in the Figure 5The illustrated embodiment is also positioned in a starting position. The vacuum suction cups 35 assigned to each other in a suction cup field 39 can be moved vertically from the illustrated rest position to the gripping position 45, as is the case, for example, in Figure 6 and 7 Each suction cup field 39 can be individually controlled. When handling a flat, plate-shaped workpiece 12, all suction cup fields 39 can be controlled in the Figure 5 The suction cups can be positioned in the depicted rest position or all in an extended gripping position 45. If a plate-shaped workpiece 12 is to be gripped, which has been machined by forming and has protrusions or projections, only individual suction cup fields 39 can be moved into the gripping position 45, as is the case, for example, in Figure 6 is shown.

[0029] According to one embodiment, for example, all vacuum suction cups 35 can be arranged in the common gripping position 45, as shown in Figure 5 As shown. If flat workpieces 12 with a lower weight are to be handled, only the vacuum suction cups 35 of the suction cup fields 39 can be activated. For example, only individual suction cup fields 39 can be activated, since other suction cup fields 39 are located in a recess or a cutout in the flat workpiece 12 and therefore cannot perform a gripping function. When handling flat workpieces 12 with a higher weight, the sealing element 42 can also be pressurized with negative pressure in addition to the vacuum suction cups 35.

[0030] In Figure 6Figure 1 shows a sectional view of the gripping device 27, in which the sealing element 42 and individual suction cups 39 are moved into the gripping position 45. When the sealing element 42 is positioned in the gripping position 45, where it lies in the gripping plane 51 of the vacuum suction cups 35, a control mechanism can be provided for handling the plate-shaped workpiece according to a first embodiment. This mechanism first applies a vacuum to the vacuum suction cups 35 and then to the sealing element 42. Alternatively, individual suction cups 39 of the gripping device 27 can be applied a vacuum, with the selection of the control mechanism for the suction cups 39 being adapted to the geometry of the plate-shaped workpiece 12 to be handled.For example, the plate-shaped workpiece to be handled may have a recess or a notch that is assigned to a suction field 39, so that it is not necessary to apply negative pressure to this suction field 39.

[0031] In Figure 7 A sectional view of the gripping device 27 in a further alternative embodiment and gripping position 45 is shown. In this embodiment, it is provided that instead of individual suction cup fields 39, as in Figure 6 As shown, only individual vacuum suction cups 35 can be moved into a gripping position 45. This arrangement has the advantage that the individual vacuum suction cups 35 are moved into the gripping position 45 in adaptation to the geometry of the plate-shaped workpiece 12 to be handled. In this gripping position 45, these vacuum suction cups 35 are also pressurized with vacuum. The vacuum suction cups 35 that are not extended can remain stationary.

[0032] A combination of the embodiment according to Figure 6 and 7 It may be possible for individual suction cup fields 39 to be moved into the gripping position 45 and adjacent to this individual vacuum suction cups 35.

[0033] Alternatively, the holding device 41 of the gripping device 27 can be controlled in such a way that the at least one sealing element 42 is positioned protruding from the suction cups 39 with the vacuum suction cup 35, so that only the sealing element 42 rests on the plate-shaped workpiece 12 to be handled, without the vacuum suction cups 35 of the at least one suction cup 39 being subjected to negative pressure.

[0034] In the embodiment described above, the sealing element 42 is preferably designed as a sealing lip. A thermoplastic elastomer can be used for this purpose.

[0035] In Figure 8An alternative embodiment of the gripping device 27 is shown. This gripping device 27 comprises, for example, nine vacuum suction cups arranged within a base area of ​​the gripping device 27, for example, a square. A sealing element 42 is provided around the outside. This sealing element 42 can be adapted to the square contour of the base body 33. Furthermore, the sealing element 42 can extend, at least partially, into the space between two adjacent vacuum suction cups 35. This creates an enlarged sealing surface. The sealing element thus has semicircular recesses 56 to which the vacuum suction cups 35 are aligned. In this embodiment, the sealing element 42 is preferably made of foam.This allows an inner circumferential surface of the sealing element 42 to be easily inserted into these semicircular recesses 56 or three-quarter circular depressions in the corner area of ​​the sealing element 42.

[0036] In Figure 9 Figure 1 shows a perspective view of a gripping device 29 with several gripping elements 27. This gripping device 29 comprises a gripping receptacle 28, on which a mounting flange 61 is provided for attachment to the handling device 26. The gripping elements 27 are preferably arranged on the gripping receptacle 28 in a grid pattern, particularly in rows and columns. These gripping elements 27 are fixed in their position and are not movable on the gripping receptacle 28.

[0037] In Figure 10 is an alternative design of the gripping device 29 to Figure 9The gripping device 29 is preferably provided with linear axes 63 on the gripping receptacle 28, which can be individually controlled with respect to a direction of travel, in particular in the Y direction. The gripping devices 27 are provided on these linear axes 63, and it can also be provided that the gripping devices 27 are variable along the length of the linear axes 63 and / or in their distance from each other.

[0038] The linear axes 63 can also be provided on at least one further linear axis 64 oriented at a right angle to them, by means of which the distance between the gripping devices 27 can be adjusted in the X-direction. Additionally, the linear axes 63 supporting the gripping device 27 can be mounted on the at least one further linear axis 64 in such a way that their distance from each other can be varied.

Claims

1. Gripping device for a handling device (26) of a processing machine (11), in particular for handling plate-shaped workpieces (12), with a plurality of vacuum suction cups (35) provided on a base body (33), which are arranged relative to one another to form at least one suction cup field (39) and at least one suction cup field (39) can be subjected to negative pressure for handling the workpiece (12), - having at least one holding device (41) which is provided on the base body (33), has at least one sealing element (42) and surrounds the vacuum suction cups (35), and having at least one actuating device (47) for applying a negative pressure to the at least one sealing element (42) for engaging the plate-shaped workpiece (12). characterized in that the vacuum suction cups (35) can be moved individually or the vacuum suction cups (35) assigned to at least one suction cup field (39) can be moved from a rest position (38) into a gripping position (45), and in that the at least one sealing element (42) is provided on the base body (33) so as to be movable up and down relative to a gripping plane (51) formed by the vacuum cups (35), and the at least one sealing element (42) is arranged to be movable in height on the base body (33) by means of a drive (53) of the actuating device (47) and is arranged in an initial position (44) above a gripping plane (51) formed by the vacuum cups (35) and can be positioned in a gripping position (45) in the gripping plane (51) formed by the vacuum cups (35) or projecting with respect to the gripping plane (51).

2. Gripping device according to claim 1, characterized in that the suction cup fields (39) provided on the base body (33) are arranged inside the externally circumferential sealing element (42).

3. Gripping device according to claim 1, characterized in that for each suction cup field (39) or for at least one group of several suction cup fields (39), an externally circumferential sealing element (42) is provided on the base body (33).

4. Gripping device according to one of the preceding claims, characterized in that the actuating device (47) has at least one valve (48) for applying a negative pressure, which can be actuated separately from at least one valve for actuating the vacuum suction cups (35) and / or the at least one suction cup field (39).

5. Gripping device according to claim 4, characterized in that the at least one valve (48) of the actuating device (47) is provided in the suction cup field (39) or is assigned to the suction cup field (39), which is surrounded by the sealing element (42).

6. Gripping device according to one of claims 1 to 5, characterized in that the at least one suction cup field (39) is movable in height relative to the base body (33).

7. Gripping device according to claim 1 or 6, characterized in that, after the at least one suction cup field (39) has been placed on the workpiece (12) to be handled, the at least one sealing element (42) can be transferred into a gripping position (45) and the vacuum suction cups (35) of the at least one suction cup field (39) and subsequently the sealing element (42) or both can be simultaneously subjected to negative pressure.

8. Gripping device according to claim 1, characterized in that the drive (53) is designed as a reciprocating piston drive, in particular a pneumatic cylinder, or as a linear drive or electromotive or electromagnetic drive.

9. Gripping device according to one of the preceding claims, characterized in that the sealing element (42) is designed as a circumferential sealing lip, which is preferably made of an elastic material, for example an elastomer or a foam material.