Apparatus for supporting a workpiece during thermal workpiece processing, comprising a device for cleaning the workpiece support

Abstract

The invention relates to an apparatus (12) for supporting a preferably planar workpiece (2) during thermal, in particular cutting, workpiece processing, said apparatus comprising a workpiece support (13) which extends endlessly in a movement direction (14) and which, after the workpiece processing, can be moved by means of a support movement in the movement direction (14) in order to clear products of the workpiece processing from the workpiece support (13). On a side facing the workpiece, the workpiece support (13) is provided with supporting elements that are designed to support the workpiece (2) during processing. A partial length of the workpiece support (13), which extends in the movement direction (14) and, during the workpiece processing, is occupied by the workpiece (2), forms, after the workpiece support (13) has been cleared, a cleared partial length of the workpiece support (13). In order to clean the supporting elements of the workpiece support (13), a cleaning device (20) is provided which, by virtue of the support movement, cleans the supporting elements of the cleared partial length of the workpiece support (13). A machine arrangement (1) for thermal workpiece processing comprises an apparatus (12) of the above type.

Description

[0001] Device for holding a workpiece during thermal workpiece machining, with a device for cleaning the workpiece support

[0002] The invention relates to a device for supporting a workpiece, preferably a plate-shaped workpiece, in particular a sheet metal, during thermal, in particular separating, workpiece processing, with a workpiece support that extends endlessly in one direction of movement of the workpiece support and which, following the workpiece processing, can be moved in the direction of movement for unloading the workpiece support of products of the workpiece processing.

[0003] • wherein the workpiece support has a workpiece side and is provided on the workpiece side with support elements designed to hold the workpiece during machining and

[0004] • wherein the workpiece support has a partial length extending in the direction of movement and loaded with the workpiece during workpiece processing, which forms an unloaded partial length after the workpiece support has been unloaded from the products of workpiece processing.

[0005] The invention also relates to a mechanical arrangement for the thermal, in particular separating, processing of a preferably plate-shaped workpiece, in particular a sheet metal, with a processing unit for workpiece processing and with a device of the aforementioned type for storing the workpiece during workpiece processing.

[0006] During thermal machining, such as thermal sheet metal processing, material from the workpiece melts and / or slag forms. Molten workpiece material and slag are deposited on the workpiece support, particularly on the tips of the support elements that are in direct contact with the workpiece. These deposits can contaminate and even damage the surface of the workpiece. Therefore, regular cleaning, especially of the support element tips, is essential. Additionally or alternatively, the workpiece support elements must be replaced after a certain period of use.

[0007] A generic machine arrangement with a generic device for holding a workpiece is offered by TRUMPF SE + Co. KG, Johann-Maus-Straße 2, 71254 Ditzingen, Germany, under the name "TruLaser 8000 Coil Edition". In the "TruLaser 8000 Coil Edition", sheet metal unwound from a coil is cut in a cutting cell using a laser beam. After passing through a straightening unit, a length of sheet metal unwound from a coil is transferred to an endless support belt located inside the cutting cell. This belt extends beyond the cutting cell in the direction of material flow to an unloading area of ​​the "TruLaser 8000 Coil Edition". The support belt features support strips with workpiece-side points. The length of sheet metal to be processed is positioned inside the cutting cell for processing by the support strip belt, which moves in its direction of movement.During the cutting process, the conveyor belt, loaded with the sheet metal to be processed on its upper run, remains stationary. After processing is complete, the conveyor belt is set in motion. This discharges the products from the previous sheet metal processing from the cutting cell and transports them to the unloading area of ​​the known machine arrangement. Simultaneously, the next sheet metal length to be processed is fed into the cutting cell. In the unloading area, the good parts produced during the previous sheet metal processing are removed from the conveyor belt. Any residual material, also generated during the previous sheet metal processing, is then shredded and discharged at the deflection point of the conveyor belt onto a scrap conveyor located below the deflection point.

[0008] The object of the present invention is to ensure the long-term functionality of the support elements of a workpiece support that holds a workpiece during thermal processing without significantly impairing the productivity of the overall process.

[0009] According to the invention, this problem is solved by the device according to claim 1 for storing a workpiece during thermal processing and by the machine arrangement according to claim 14.

[0010] In the case of the invention, the cleaning of the workpiece support elements is effected by the movement that the workpiece support performs during the unloading process, in particular for removing the machining products from the working area of ​​the machining unit. Accordingly, the cleaning of the workpiece support elements can be carried out concurrently with the unloading process, thus avoiding undesirable downtime. Each of the workpiece support elements is cleaned with every revolution of the endless workpiece support. This maximizes the service life of the workpiece support elements. Downtime of the device and the machine arrangement according to the invention, such as that associated with replacing contaminated workpiece support elements, is minimized.The cleaning of the support elements preferably takes place outside the working area of ​​the processing unit. Support strips are particularly suitable as support elements.

[0011] Specific embodiments of the device according to claim 1 and the machine arrangement according to claim 14 are set forth in dependent claims 2 to 13 and 15. In a preferred embodiment of the invention, the workpiece support is designed in the manner of a support belt, which has on an upper run the partial length loaded with the workpiece during workpiece processing (claim 2).

[0012] To unload the support belt, it is moved in the direction of travel along with the support movement. A previously unloaded portion of the workpiece support thus enters the area of ​​the cleaning device and is cleaned there due to the support movement.

[0013] In a further preferred embodiment of the invention, the cleaning of the support elements is carried out when the previously loaded and now unloaded portion of the support belt has reached the lower run of the support belt (claim 3). The cleaning operations can be performed on the lower run of the support belt without disrupting other processes on the device and / or the machine arrangement according to the invention. Sufficient space is available on the lower run of the support belt to accommodate the tools required for cleaning the support elements. In principle, cleaning the support elements of the unloaded portion of the support belt would also be conceivable, for example, on the upper run or in the area where the support belt deflects.

[0014] According to the invention, various designs are suitable for the cleaning device for cleaning the support elements of the workpiece support.

[0015] According to claim 4, a further development of the invention provides a cleaning device for the mechanical cleaning of the support elements of the workpiece support. The cleaning of the support elements can be carried out, for example, by scraping, grinding, chipping, or rubbing them with suitable tools due to the movement of the workpiece support. A cleaning device comprising at least one cleaning element is preferred according to the invention. This cleaning element cleans the support elements of the unloaded portion of the workpiece support by allowing the support elements of the unloaded portion of the workpiece support to be movable relative to the cleaning element due to the movement of the workpiece support (claim 5).

[0016] For the sake of simple design, a cleaning element that is stationary in the direction of movement of the workpiece support is preferred (claim 6). In this design, the relative movement of the support elements and the cleaning element of the cleaning device required for cleaning the support elements is generated solely by the movement of the workpiece support. Accordingly, a separate drive for the cleaning device is not required.

[0017] In a further embodiment of the invention, a support structure of the device according to the invention is used for the stationary mounting of the cleaning element of the cleaning device (patent claim 7).

[0018] According to the invention, a cleaning brush with cleaning bristles is preferred as the cleaning element of the cleaning device. Due to the movement of the workpiece, the support elements of the unloaded portion of the workpiece support are passed over the cleaning brush, thereby cleaning the support elements (claim 8). A cleaning brush of the type according to the invention is characterized in particular by a simple and space-saving design and a long service life. Preferably, in the case of the invention, cleaning brushes are used for the mechanical cleaning of the support elements of the workpiece support. In particular, the immersion depth of the support elements in the cleaning brush, the orientation of the cleaning brushes relative to the support elements to be cleaned, and the material of the cleaning bristles are selected according to the specific application such that the support elements are cleaned thoroughly yet gently.

[0019] To maximize the cleaning effect, a further development of the invention provides that the cleaning bristles of the cleaning brush are inclined, at least initially, in the direction of movement or against the direction of movement of the workpiece support relative to the support elements passing over them, and that the cleaning bristles are elastically deflectable in the direction of movement of the workpiece support by the support elements passing over them (claim 9). Due to these features of the invention, the cleaning bristles effectively clean and process the support elements during the support movement, both on the side that leads and on the side that lags behind in the direction of the support movement.

[0020] Claim 10 relates to an inventive design with support elements in the form of support strips. The support strips form a support plane and extend in the vertical projection into the support plane with a longitudinal direction transverse to the direction of movement of the workpiece support. Such support strips are frequently provided with support points on which a workpiece rests directly with its underside during machining.

[0021] In a preferred embodiment of the invention according to claim 10, the cleaning brush is inclined at an angle in the vertical projection into the support plane relative to the support strips through which the cleaning bristles pass (claim 11). This inclination of the cleaning brush according to the invention ensures that, during their movement relative to the cleaning brush due to the support movement, the support strips do not all come into contact with the cleaning bristles of the cleaning brush at once along their entire length. Instead, a contact limited in the longitudinal direction of the support strips is established between the support strips and the cleaning bristles of the cleaning brush, which moves along the entire length of the support strips.This prevents unwanted vibrations of the support strips and the workpiece support equipped with the support strips, such as would otherwise be expected if the support strips were to come into hard contact with the cleaning bristles of the cleaning brush. Undesirable vibrations of this type are particularly effectively avoided in the design according to claim 12. Two arrow-shaped cleaning brushes are assigned to one and the same support strip of the workpiece support, each of which cleans a portion of the support strips passing over it.

[0022] To achieve a particular cleaning effect, as further described in claim 13 of the invention, several cleaning elements are used that are offset from one another in the direction of movement of the workpiece support and are passed by each of the support elements in succession. The cleaning elements can, in particular, be cleaning brushes of the type described above. Several pairs of arrow-shaped cleaning brushes can follow one another in the direction of movement of the workpiece support.

[0023] According to claim 15, the machine arrangement according to the invention is designed for the thermal, in particular cutting, processing of a workpiece in the form of a sheet metal unwound from a coil. A processing unit for cutting the workpiece using a laser beam can be provided as the processing unit.

[0024] The invention is explained in more detail below with reference to exemplary schematic diagrams. These show:

[0025] Figure 1 shows a machine arrangement for sheet metal processing from coil, with an endless workpiece support and a cleaning device for cleaning the support rails of the workpiece support using cleaning brushes.

[0026] Figure 2 shows the cleaning device of the machine arrangement according to Figure 1.

[0027] Figure 3 is a representation illustrating the operation of the cleaning device according to Figures 1 and 2, Figure 4 shows the cleaning device according to Figures 1 to 3 during cleaning of the support rails of the workpiece support of the machine arrangement according to Figure 1 and

[0028] Figure 5 shows the cleaning device according to Figures 1 to 3 with a different orientation of the cleaning brushes compared to Figure 4.

[0029] A machine arrangement 1 shown in Figure 1 is used for the separating processing of a workpiece in the form of a strip-shaped sheet metal 2, which in its initial state is wound as a coil 3 on a reel 4. Adjacent to the reel 4 is a conventional straightening device 5 with straightening rollers 6.

[0030] After passing through the straightening device 5, the sheet 2 unwound from the coil 3 is fed section by section in a feed direction 7 to a laser cutting machine 8, which is provided as a processing unit of the machine arrangement 1, for thermal cutting. For cutting the sheet 2, a laser cutting head 10 is movable in the usual manner with a two-axis horizontal working movement inside an enclosure 9 of the laser cutting machine 8. The laser cutting head 10 moves within a working area 11 of the laser cutting machine 8, the boundaries of which, located in the feed direction 7, are indicated in Figure 1 by vertical dashed lines.

[0031] A device 12 is provided for storing the sheet metal 2 during the cutting process inside the housing 9 of the laser cutting machine 8.

[0032] The device 12 has a support structure (not shown in Figure 1 for the sake of simplicity) and a conventional endless support strip 13 as a workpiece support, which is movably guided on the support structure of the device 12 in a direction of movement 14. The support strip 13 extends through the housing 9 of the laser cutting machine 8 and beyond over an unloading area 15 of the machine arrangement 1, which is directly adjacent to the laser cutting machine 8.

[0033] In the unloading area 15, an automated unloading unit with a suction frame 16 is provided. A conventional scrap conveyor belt 18 is arranged below a deflection point 17 of the support belt 13 located near the unloading area 15.

[0034] In the usual manner, the support strip 13 is provided on one side of the workpiece with support elements in the form of metal support strips 19 (Figures 4 and 5). The support strips 19 form a horizontal support plane in which they run perpendicular to the direction of movement 14 of the support strip 13. On the workpiece side, the support strips 19 are toothed and accordingly provided with points on which the sheet metal 2 to be processed and subsequently the machined products rest during processing.

[0035] During the sheet metal cutting process carried out by the laser cutting head 10 inside the laser cutting machine 8, the support strip 13, with the portion of the sheet metal 2 supported on its upper run, remains stationary. Due to the nature of the process, material from the sheet metal 2 melts during the thermal cutting operation. Slag is also formed. Both the molten material and the slag are deposited on the support strips 19 of the portion of the support strip 13 loaded with the sheet metal 2 during the cutting process, and particularly at the tips of the support strips 19.

[0036] After completion of the cutting process, the support belt 13 is set in motion in the direction of movement 14. Due to the associated support movement, the portion of the support belt 13 now loaded with the products of the cutting sheet metal processing enters the unloading area 15 of the machine arrangement 1. There, the good parts produced during the preceding sheet metal processing are unloaded from the now stationary support belt 13 by means of the suction frame 16. The residual grid, also produced during the cutting sheet metal processing, initially remains on the support belt 13, but this has already been reduced in size by the laser cutting head 10 during the cutting of the good parts. After the good parts have been unloaded, the support belt 13 continues to move in the direction of movement 14 with another support movement.As a result, the shredded residual grid from the preceding sheet metal processing is discharged onto the scrap conveyor belt 18 at the deflection point 17. The shredded residual grid is then conveyed away from the immediate vicinity of the machine arrangement 1 by means of the scrap conveyor belt 18.

[0037] Synchronously with the cycle times of the processed products generated during sheet metal processing on the laser cutting machine 8, the next partial length of sheet metal 2 to be processed is fed to the laser cutting machine 8 and the support strip 13 located there, and the processes described above are repeated.

[0038] During the manufacturing process carried out on the machine arrangement 1, each section of the support strip belt 13, previously loaded with the sheet metal 2 during processing and subsequently with the products of the separating sheet metal processing, reaches the lower run of the support strip belt 13 after unloading and passing the deflection point 17. A cleaning device 20 is fixedly mounted on the support structure of the device 12 in the direction of movement 14. The cleaning device 20 cleans the support strips 19 of the support strip belt 13, which were previously contaminated during the separating sheet metal processing.

[0039] Due to support movements performed by the support strip 13 for unloading, the cleaning device 20 is passed by partial lengths of the support strip 13 that were previously loaded with the sheet metal 2 during processing and are now unloaded.

[0040] The design and operation of the cleaning device 20 are described in detail with reference to Figures 2 to 5. As shown in Figure 2, the cleaning device 20 has a rectangular mounting frame 21 to which it is connected to the support structure of the device 12 (not shown). Several cleaning brushes 22 with stainless steel cleaning bristles 23 are attached to the mounting frame 21 as cleaning elements of the cleaning device 20. When the cleaning device 20 is installed on the support structure of the device 12, the free ends of the cleaning bristles 23 of the cleaning brushes 22 point towards the lower run of the support strip 13.

[0041] In the illustrated example, the cleaning brushes 22 form a total of four cleaning brush pairs. The cleaning brush pairs are offset from each other in the direction of movement 14 of the support strip 13 and each has an arrow-shaped profile. The cleaning bristles 23 of a cleaning brush pair clean a support strip 19 together.

[0042] Figure 3 illustrates in a highly schematic form the cleaning of a support strip 19 in the vertical projection into the horizontal support plane formed by the support strips 19.

[0043] As shown in Figure 3, the cleaning brushes 22 of each pair of cleaning brushes are inclined at an angle o in the perpendicular projection into the support plane relative to a support bar 19 that passes over the cleaning bristles 23 of the cleaning brushes 22, forming the aforementioned arrow shape. Consequently, during the movement relative to the cleaning device 20 in the direction of movement 14, the support bar 19 does not run onto the cleaning bristles 23 of the cleaning brushes 22 at once along its entire length.Instead, a contact area C, limited in the longitudinal direction of the support strip 19, is formed between the support strip 19 and the cleaning bristles 23 of each of the cleaning brushes 22 of a cleaning brush pair. This contact area C moves along the entire length of the support strip 19 due to the movement of the support strip 19 relative to the cleaning brushes 22 of the respective cleaning brush pair in the direction of movement 14 (dashed arrows in Figure 3). By preventing a hard collision between the support strips 19 and the cleaning brushes 22, undesirable vibrations of the support strips 19 and the entire support strip band 13 are avoided during cleaning.

[0044] As shown in Figure 4, the support strips 19 overlap the cleaning bristles 23 of the cleaning brushes 22 to such an extent that at least the tips of the support strips 19 are reliably and thoroughly cleaned of deposits such as molten material or slag as they pass over the cleaning bristles 23. The immersion depth of the support strips 19 against the support bristles 23 can be, for example, on the order of 2 mm. The plane of representation in Figure 4 is perpendicular to the support plane defined by the support strips 19.

[0045] In Figure 4, the cleaning brushes 22 of the cleaning device 20 with their cleaning bristles 23 are aligned essentially parallel to the support rails 19.

[0046] Possibilities for optimizing the cleaning effect achievable by means of the cleaning device 20 are shown in Figure 5.

[0047] In Figure 5, in a plane of representation that also runs perpendicular to the support plane formed by the support strips 19, the two left cleaning brushes 22 of the cleaning device 20 with their cleaning bristles 23 are initially inclined relative to the support strips 19 passing them in the opposite direction of movement 14 of the support strip band 13.

[0048] When a support bar 19, during its movement in the direction of movement 14, runs onto the cleaning bristles 23 of one of the two cleaning brushes 22 on the left in Figure 5, the cleaning bristles 23 are elastically bent upwards due to the pressure exerted by the support bar 19 and move along the surface of the support bar 19 that is advancing in the direction of movement 14. Contaminants present there are scraped off the support bar 19 by the cleaning bristles 23 deflected in the vertical direction. Once a support bar 19 has passed the respective cleaning brush 22 in the direction of movement 14, the cleaning bristles 23 of the cleaning brush 22 elastically return to their initial position as shown in Figure 5.

[0049] In contrast to the two left cleaning brushes 22, the two right cleaning brushes 22 in Figure 5 are aligned in the direction of movement 14 of the support strips.

[0050] 19 inclined. When a support strip 19 runs onto the cleaning bristles 23 of one of the cleaning brushes 22 on the right in Figure 5, the cleaning bristles 23 of this cleaning brush 22 are initially bent downwards by the support strip 19 before, due to their elasticity, they gradually return to their original orientation with an upward movement as they pass the support strip 19. During the upward movement, the cleaning bristles 23 move over the surface of the support strip 19 that lags behind in the direction of movement 14 and remove adhering contaminants.

Claims

Patent claims 1. Device for storing a workpiece (2), preferably a plate-shaped workpiece (2), in particular a sheet metal, during a thermal, in particular separating, workpiece processing, with a workpiece support (13) which extends endlessly in a direction of movement (14) of the workpiece support (13) and which, following the workpiece processing, is movable by means of a support movement in the direction of movement (14) for unloading the workpiece support (13) of products of the workpiece processing, • wherein the workpiece support (13) has a workpiece side and is provided on the workpiece side with support elements (19) designed for supporting the workpiece (2) during machining and • wherein the workpiece support (13) has a partial length extending in the direction of movement (14) and loaded with the workpiece (2) during workpiece processing, which forms an unloaded partial length after the workpiece support (13) is unloaded from the products of the workpiece processing, characterized in that a cleaning device (20) is provided for cleaning the support elements (19) of the workpiece support (13), which cleans the support elements (19) of the unloaded partial length of the workpiece support (13) due to the support movement.

2. Device according to claim 1, characterized in that the workpiece support (13) is designed in a band-like manner and has on an upper run the partial length loaded with the workpiece (2) during workpiece processing.

3. Device according to claim 2, characterized in that, • that the band-like workpiece support (13) has a lower run and • that the cleaning device (20) cleans the support elements (19) of the unloaded part length of the workpiece support (13) on the lower run.

4. Device according to one of the preceding claims, characterized in that a device for mechanically cleaning the support elements (19) of the workpiece support (13) is provided as a cleaning device (20) for cleaning the support elements (19).

5. Device according to one of the preceding claims, characterized in that the cleaning device (20) for cleaning the support elements (19) has at least one cleaning element (22) which cleans the support elements (19) of the unloaded partial length of the workpiece support (13) in that the support elements (19) of the unloaded partial length of the workpiece support (13) are movable relative to the cleaning element (22) due to the support movement.

6. Device according to claim 5, characterized in that the cleaning element (22) of the cleaning device (20) is arranged in a stationary position in the direction of movement (14) of the workpiece support (13).

7. Device according to claim 6, characterized in that, • that the device has a support structure on which the workpiece support (13) is guided in its direction of movement (14) and • that the cleaning element (22) of the cleaning device (20) is arranged stationary on the support structure in the direction of movement (14) of the workpiece support (13).

8. Device according to one of claims 5 to 7, characterized in that a cleaning brush with cleaning bristles (23) is provided as the cleaning element (22) of the cleaning device (20), which are passed by the support elements (19) of the discharged part length of the workpiece support (13) due to the support movement and thereby clean the support elements (19).

9. Device according to claim 8, characterized in that, • that the cleaning bristles (23) of the cleaning brush are inclined at least initially in the direction of movement (14) or against the direction of movement (14) of the workpiece support (13) relative to the support elements (19) passing through the cleaning bristles (23) and • that the cleaning bristles (23) of the cleaning brushes are elastically deflectable in the direction of movement (14) of the workpiece support (13) by the support elements (19) passing through them.

10. Device according to claim 8 or claim 9, characterized in that, • that support elements (19) are provided as support strips which form a support plane and which extend in the vertical projection into the support plane with a longitudinal direction transverse to the direction of movement (14) of the workpiece support (13) and • that the cleaning bristles (23) of the cleaning brush pass over the support strips of the discharged part length of the workpiece support (13) due to the support movement and thereby clean the support strips.

11. Device according to claim 10, characterized in that the cleaning brush is inclined at an angle in the vertical projection into the support plane relative to the support strips passing the cleaning bristles (23).

12. Device according to claim 11, characterized in that, • that a further cleaning brush (22) is provided as a further cleaning element with cleaning bristles (23) which are passed by the support strips of the discharged part length of the workpiece support (13) due to the support movement, • that each of the two cleaning brushes is assigned to the same support strip for cleaning a portion of the length and • that the two cleaning brushes are inclined at an angle in opposite directions to the support strips passing through the cleaning bristles (23) of the cleaning brushes in the vertical projection into the support plane.

13. Device according to one of claims 5 to 12, characterized in that several cleaning elements (22) are provided that are offset from one another in the direction of movement (14) of the workpiece support (13).

14. A mechanical arrangement for the thermal, in particular separating, processing of a preferably plate-shaped workpiece (2), in particular a sheet metal, comprising a processing unit (8) for workpiece processing and a device (12) for holding the workpiece (2) during workpiece processing (8), characterized in that the device (12) for holding the workpiece (2) during workpiece processing is the device according to one of claims 1 to 13.

15. Machine arrangement according to claim 14, characterized in that the machine arrangement is designed for thermal, in particular separating, processing of a workpiece (2) in the form of a sheet metal unwound from a coil (3).

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