Workpiece Fixing Device, Grinding Machine, and Method for Fixing a Workpiece

Abstract

A workpiece fixing device for fixing a workpiece by vacuum for machining thereof includes a support device on which the workpiece can be laid for fixing, and at least one vacuum chamber which is formed starting from the support device. The workpiece fixing device has a first fixing region and a second fixing region different from the first fixing region. The support device has a first support channel profile in the first fixing region and a second support channel profile different from the first support channel profile in the second fixing region.

Claims

1. A workpiece fixing device for fixing a workpiece by vacuum for machining thereof, comprising: a support device on which the workpiece can be laid for fixing, and at least one vacuum chamber which is formed starting from the support device, wherein the support device comprises a first fixing region and a second fixing region different from the first fixing region, wherein the support device has a first support channel profile in the first fixing region and a second support channel profile different from the first support channel profile in the second fixing region.

2. The workpiece fixing device according to claim 1, further comprising a slide device arranged in the first fixing region, wherein the slide device and the support device are arranged so as to be movable relative to one another.

3. The workpiece fixing device according to claim 2 wherein the slide device and the support device are arranged so as to be movable translationally and/or rotationally relative to one another.

4. The workpiece fixing device according to claim 1, wherein the slide device and/or the support device are configured so they can be moved to and fro, relative to one another, between a first slide position and a second slide position different from the first, wherein the slide device and/or the support device are movable to and fro translationally and/or rotationally, relative to one another between the first slide position and the second slide position, and wherein the slide device and the support device, in the first slide position of the slide device, form a first suction hole profile, and in the second slide position of the slide device, form a second suction hole profile different from the first suction hole profile.

5. The workpiece fixing device according to claim 4 wherein the first suction hole profile is the first support channel profile.

6. The workpiece fixing device according to claim 2 wherein the slide device has one or more sliding units which are configured to be moved to and fro, relative to the support device, dependently or independently of one another, between the first slide position and the second slide position, wherein the one or more sliding units are configured to be moved to and fro, translationally and/or rotationally, relative to the support device, dependently or independently of one another, between the first slide position and the second slide position.

7. The workpiece fixing device according to claim 1, wherein in comparison with the second support channel profile, the first support channel profile has a higher number of suction channels per surface area unit, and/or wherein in comparison with the second fixing region, the first fixing region has a smaller superficial extent.

8. The workpiece fixing device according to the preceding claim 7, wherein the first fixing region and the second fixing region extend over a same length in a main machining direction of the workpiece to be machined; and/or wherein the first fixing region extends over a smaller width than the second fixing region orthogonally to the main machining direction of the workpiece to be machined.

9. The workpiece fixing device according to claim 1 further comprising a sensor device to detect a workpiece arranged on the support device.

10. The workpiece fixing device according to claim 9 wherein the sensor device is configured to detect a position and/or a position change and/or a position region and/or a size and/or a length and/or a width and/or a height of the workpiece on the support device.

11. The workpiece fixing device according to claim 10 wherein the sensor device detects the position and/or the position change and/or the position region and/or the size and/or the length and/or the width and or the height of the workpiece on a suction surface of the support device.

12. The workpiece fixing device according to claim 9 wherein the at least one vacuum chamber has a chamber volume which is designed to be variable in size, wherein the chamber volume is variable between a first chamber volume and a second chamber volume different from the first, and wherein the chamber volume of the at least one vacuum chamber is variable depending on the position region detected by the sensor device and/or depending on the size and/or length and/or width and/or height of the workpiece detected by the sensor device,

13. The workpiece fixing device according to claim 1 wherein the at least one vacuum chamber has a chamber volume which is designed to be variable in size, wherein the chamber volume is variable between a first chamber volume and a second chamber volume different from the first, and/or wherein the at least one vacuum chamber has a partition wall device which is configured to change the chamber volume of the at least one vacuum chamber between the first chamber volume and the second chamber volume.

14. The workpiece fixing device according to claim 13 further comprising an actuating device configured to adjust the partition wall device between a first setting position and a second setting position different from the first, wherein the at least one vacuum chamber has the first chamber volume in the first setting position of the partition wall device and has the second chamber volume in the second setting position of the partition wall device.

15. The workpiece fixing device according to claim 14, wherein the actuating device is configured as a manually operated actuating device, and/or is configured as an automatically operated actuating device.

16. The workpiece fixing device according to claim 1 further comprising a suction device for generating a vacuum in the vacuum chamber with a suction power, and/or a control device connected for signaling purposes to a sensor device and/or an actuating device and/or a partition wall device and/or the suction device.

17. The workpiece fixing device according to claim 1 wherein the support device comprises a stationary table unit; and/or a transport unit configured to transport the workpiece to be machined in a main machining direction; wherein the stationary table unit has a longitudinal pattern profile; and/or the transport unit is arranged so as to be movable relative to the stationary table unit; and/or the transport unit has a hole pattern profile; and/or the transport unit is a conveyor belt or a transport mat.

18. A grinding machine comprising a workpiece fixing device according to claim 1 for fixing one or more grinding appliances for machining a workpiece.

19. A method for fixing a workpiece by vacuum for machining thereof, comprising: providing a workpiece fixing device according to claim 1; detecting a workpiece arranged on a support device of the workpiece fixing device; and allocating the detected workpiece to a first fixing region or a second fixing region different from the first fixing region.

20. The method according claim 19, further comprising: adjusting a size of a chamber volume of at least one vacuum chamber of the workpiece fixing device depending on the detected workpiece; and/or adjusting a suction hole profile in the support device in the allocated fixing region depending on the detected workpiece; and/or adjusting a suction power of a suction device depending on a detected position change of the workpiece, wherein adjustment of the suction power of the suction device comprises increasing the suction power when the position change of the workpiece lies above a threshold value.

Description

DESCRIPTION OF THE DRAWINGS

[0067] Preferred embodiments of the invention are explained as examples below with reference to the appended figures.

[0068] FIG. 1 shows an isometric view of a preferred embodiment of a workpiece fixing device;

[0069] FIG. 2 shows a top view of a conveyor belt of the workpiece fixing device illustrated in FIG. 1;

[0070] FIG. 3 shows a detail view of a table unit of the workpiece fixing device illustrated in FIG. 1;

[0071] FIG. 4 shows a sectional view of a further preferred embodiment of a workpiece fixing device, which is based on the embodiment of the workpiece fixing device illustrated in FIG. 1; and

[0072] FIG. 5 shows a schematic flow diagram of a preferred embodiment of a method for fixing a workpiece with a workpiece fixing device.

DETAILED DESCRIPTION

[0073] FIG. 1 shows an isometric view of a preferred embodiment of a workpiece fixing device 1, for fixing a workpiece 2 for machining thereof. A grinding machine (not shown), for example a wide belt grinding machine, may fix workpieces 2 by means of such a workpiece fixing device 1 for machining.

[0074] The workpiece fixing device 1 has a support device 3. In this preferred embodiment, the support device 3 comprises a stationary table unit 10 and a transport unit 20. The transport unit 20 is arranged so as to be movable relative to the table unit 10 and is configured as an endless conveyor belt or endless transport mat. For machining the workpiece, the transport unit 20 conveys the workpiece 2 to be machined in a main machining direction H along a machining appliance, for example a grinding appliance (not shown). For this, the workpiece to be machined is first arranged on the support device 3, or in the present case, the transport unit 20.

[0075] The support device 3 extends between a suction surface 11 and an extraction surface 12. The workpiece 2 to be machined is laid on the suction surface 11 of the support device 3 for machining and fixed there. To fix the workpiece 2 to the support device 3, the workpiece fixing device 1 has a vacuum chamber 30 which extends starting from the extraction surface 12 of the support device 3. Via a vacuum connection 70, a vacuum is generated in the vacuum chamber 30, by means of which air is aspirated from the environment through the suction surface 11. This results in a vacuum which sucks the workpiece 2 onto the suction surface 11. The vacuum connection 70 is fluidically connected to a suction device (not shown) which aspirates the air.

[0076] FIG. 1 shows that the workpiece fixing device 1 has a first fixing region B1 and a second fixing region B2 different from the first fixing region B1. In comparison with the second fixing region B2, the first fixing region B1 has a smaller superficial extent. The first and second fixing regions B1, B2 here extend over the same length in the main machining direction H of the workpiece 2 to be machined. However, in comparison with the second fixing region B2, the first fixing region B1 has a smaller width orthogonally to the main extent direction.

[0077] It is provided that the support device 3 has a first support channel profile 13 in the first fixing region B1 and a second support channel profile 14, different from the first support channel profile 13, in the second fixing region B2. In comparison with the second support channel profile 14, the first support channel profile 13 has a substantially more finely pitched arrangement of the channels through which air is aspirated. This is also shown in FIG. 2, which shows a top view of a conveyor belt of the workpiece fixing device 1 illustrated in FIG. 1, on which an elongate workpiece 2 is fixed. Substantially, in comparison with the second support channel profile 14, the first support channel profile 13 has a higher number of suction channels per surface area unit.

[0078] The support device 3 of the embodiment shown in FIG. 1 has a slide device 50 in the first fixing region B1. The slide device 50 is arranged between and is movable relative to the transport unit 20 and the table unit 10. In the present exemplary embodiment, the slide device 50 can be moved to and fro, relative to the support device 3, between a first slide position and a second slide position different from the first. In cooperation with the support device 3, in the first slide position, the slide device 50 forms a first suction hole profile and in the second slide position, a second suction hole profile different from the first suction hole profile.

[0079] The slide device 50 illustrated in FIG. 1 comprises two sliding units 50a, 50b which are configured to be moved to and fro, relative to the support device 3, independently of one another, between the first slide position and the second slide position. This is shown by the detail view in FIG. 3 onto the table unit 10 of the workpiece fixing device 1 illustrated in FIG. 1. The sliding unit 50a arranged on the right is in a first slide position which is configured for fixing of larger workpieces 2. The sliding unit 50b arranged on the left is in a second slide position which is suitable for fixing smaller workpieces 2.

[0080] FIG. 4 shows a sectional view of a further preferred embodiment of a workpiece fixing device 1 which is based on the embodiment of the workpiece fixing device 1 illustrated in FIG. 1. The embodiment illustrated in FIG. 4 differs from the embodiment illustrated in FIG. 1 by the use of two vacuum chambers 30a, 30b, wherein one of the two vacuum chambers 30a has a chamber volume which is designed variably in size. The chamber volume of this vacuum chamber 30a can be changed between a first chamber volume and a second chamber volume different from the first. To change the chamber volume, the vacuum chamber 30a has a partition wall device 60 which can be adjusted between a first setting position and a second setting position different from the first. In this way, the chamber volume of the vacuum chamber 30a may be adjusted between a first chamber volume in the first setting position and a second chamber volume in the second setting position.

[0081] In order to adjust the partition wall device 60 between the first and second setting positions, the embodiment of the workpiece fixing device 1 illustrated in FIG. 4 comprises an actuating device 40. The actuating device 40 may be configured for manual operation, or—as provided here—for automatic operation.

[0082] For automatic operation of the actuating device 40, the workpiece fixing device 1 has a sensor device (not shown) and a control device (not shown).

[0083] The sensor device is configured to detect a workpiece 2 arranged on the support device 3. In the present case, the sensor device is configured to detect a position region, a size, a length, a width, and a height of the workpiece 2 on the suction surface 11 of the support device 3 on which the workpiece 2 arranged on the suction device 3 lies. In particular, the sensor device is also configured to detect a position change of the workpiece 2 arranged on the support device 3. For this, it is provided to detect the position of the workpiece at different times, and compare these with one another taking into account the transport speed and transport direction. If the comparison shows that the positions detected at different times are not identical, a position change of the workpiece has occurred. In the present preferred exemplary embodiment, this may for example cause an increase in the suction power of the suction device.

[0084] The control device is connected for signaling purposes to the sensor device, the actuating device 40, the partition wall device 60 and the suction device. The control device is configured to adjust the chamber volume of the vacuum chamber 30a depending on the position region detected by the sensor device, or the size, length, width and height of the workpiece 2 detected by the sensor device.

[0085] FIG. 5 shows a schematic flow diagram of a preferred embodiment of a method 1000 for fixing a workpiece 2 with a workpiece fixing device 1.

[0086] In the embodiment illustrated here, the method 1000 comprises the steps of detection 1010 of a workpiece 2 arranged on the support device 3, and allocation 1020 of the detected workpiece 2 to a first B1 or to a second fixing region B2 different from the first. Furthermore, the method 1000 comprises adjustment 1030 of a size of a chamber volume of at least one vacuum chamber 30, 30a, 30b depending on the detected workpiece 2, and adjustment 1040 of a suction hole profile in the support device 3 in the allocated fixing region B1, B2 depending on the detected workpiece 2.

LIST OF REFERENCE SIGNS

[0087] 1 Workpiece fixing device [0088] 2 Workpiece [0089] 3 Support device [0090] 10 Table unit [0091] 11 Suction surface [0092] 12 Extraction surface [0093] 13 First support channel profile [0094] 14 Second support channel profile [0095] 20 Transport unit, conveyor belt, transport mat [0096] 30, 30a,b Vacuum chamber [0097] 40 Actuating device [0098] 50 Slide device [0099] 50a,b Sliding units [0100] 60 Partition wall device [0101] 70 Vacuum connection [0102] B1, B2 First, second fixing region [0103] H Main machining direction