Bending press having an angle-measuring device and method for determining the bending angle

Patent metadata

Field	Value
Publication number	US-9664493-B2
Application number	US-201314408698-A
Country	US
Kind code	B2
Filing date	Jun 12, 2013
Priority date	Jun 18, 2012
Publication date	May 30, 2017
Grant date	May 30, 2017

Abstract

The invention relates to a production plant ( 1 ), in particular for folding workpieces ( 2 ) to be produced from sheet metal, comprising a bending press ( 3 ), in particular a press brake, having a press beam ( 13, 16 ), at least one bending tool ( 4 ), such as a bending punch ( 5 ) and bending die ( 6 ), which is connected to the press beam ( 13, 16 ), and at least one angle-measuring device ( 46 ) for determining an angular position of at least one limb ( 35, 36 ) of the workpiece ( 2 ) formed by a bending operation relative to a reference plane ( 41, 42 ). The angle-measuring device ( 46 ) comprises at least one inclination sensor ( 39 ) having a reference surface ( 40 ) and the inclination sensor ( 39 ) is mounted by the angle-measuring device ( 46 ) so that it can be placed with the reference surface ( 40 ) lying in contact with a surface portion of at least one of the limbs ( 35, 36 ) of the workpiece ( 2 ).

First claim

The invention claimed is:

1. A production plant comprising
a bending press having a press beam,
at least one bending tool connected to the press beam, and
at least one angle-measuring device for determining an angular position of at least one limb of a workpiece formed by a bending operation of the bending press with the bending tool relative to a reference plane of the bending press,
wherein the angle-measuring device comprises at least one inclination sensor with a reference plane based on the direction of gravity and contained inside the inclination sensor itself, the inclination sensor having a reference surface, and the inclination sensor is supported by the angle-measuring device so that the inclination sensor is placed with the reference surface lying in direct contact with a surface portion of said at least one of the limbs of the workpiece,
wherein the inclination sensor measures an angle between the reference surface and the direction of gravity and thereby determines an angle of inclination of at least one of the limbs of the workpiece relative to the reference plane of the bending press or relative to the reference plane of the inclination sensor.

2. The production plant according to claim 1 , wherein the inclination sensor is a single axis sensor.

3. The production plant according to claim 1 , wherein the inclination sensor is a biaxial sensor.

4. The production plant according to claim 1 , wherein several differently oriented inclination sensors co-operate with the reference surface so that the angle-measuring device has a total measuring range for determining inclination and the total measuring range is subdivided into several partial measurement ranges each assigned to an inclination sensor.

5. The production plant according to claim 1 , wherein the angle-measuring device is disposed adjacent to the bending tool of the bending press.

6. The production plant according to claim 1 , wherein the angle-measuring device is disposed at a distance from the bending tool of the bending press.

7. The production plant according to claim 1 , wherein the inclination sensor is held in contact with the surface portion of the limb of the workpiece to be produced by a holder.

8. The production plant according to claim 7 , wherein the holder of the inclination sensor is selected from the group consisting of magnetic holders, a detachable adhesive connection, suckers, spring clamps, mechanical clamps, spring-assisted holders, manual holder, and adhesion.

9. The production plant according to claim 1 , wherein the inclination sensor is disposed on and connected to an elastically deformable support element, and the support element is connected to the bending tool, and the inclination sensor is disposed at a distance apart from a working plane defined by the press beam the working plane being in a vertical direction with reference to the working plane.

10. The production plant according to claim 1 , wherein the angle-measuring device comprises at least two inclination sensors for determining the angular position configured for placement respectively on a limb of the workpiece to be produced formed by a bending operation.

11. The production plant according to claim 1 , wherein the angle-measuring device comprises a rotary rate sensor, the measurement values of which can be correlated with the measurement values of the inclination sensor in a control device of the angle-measuring device.

12. The production plant according to claim 11 , wherein the angle-measuring device comprises a temperature sensor, the measurement values of which can be transferred to a control device of the angle-measuring device for a temperature compensation of the measurement values from the inclination sensor and rotary rate sensor.

13. The production plant according to claim 12 , wherein the inclination sensor and/or the rotary rate sensor and/or the temperature sensor are based on MEMS technology.

14. A method of determining an angular position of at least one limb of a workpiece comprising:
forming the workpiece by a bending operation relative to a reference plane of a bending press used to perform the bending operation;
providing an angle-measuring device comprising at least one inclination sensor with a reference plane based on the direction of gravity and contained within the inclination sensor itself;
disposing the at least one inclination sensor so that a reference surface of said inclination sensor lies in direct contact with a surface portion of at least one of the limbs of the workpiece; and
measuring the angle between the reference surface and the direction of gravity with the inclination sensor and thereby
determining an angle of inclination of the at least one limbs of the workpiece relative to the reference plane of the bending press or relative to the reference plane of the inclination sensor.

15. The method according to claim 14 , wherein the angle of inclination determined by the inclination sensor is determined using a single axis sensor.

16. The method according to claim 14 , wherein the angle of inclination determined by the inclination sensor is determined using a biaxial sensor.

17. The method according to claim 14 , wherein the angle of inclination determined by the inclination sensor is determined on the basis of MEMS technology.

18. The method according to claim 14 , wherein the inclination sensor is held in contact with the surface portion of the limb of the workpiece during the bending operation.

19. The method according to claim 14 , wherein the inclination sensor is held stationary in contact with the surface portion of the limb of the workpiece by a holder.

20. The method according to claim 14 , wherein prior to running the bending operation, an operation of referencing the inclination sensor is run.

21. The method according to claim 14 , wherein after at least partially running a bending operation, the bending tool is opened to the extent that two limbs of the at least one limb are held between the bending tools without any deforming pressing force being applied and in this position the angle of inclination of at least one of the limbs of the workpiece to be produced is determined.

22. The method according to claim 21 , wherein an inclination sensor is placed respectively on each of the two limbs of the workpiece ( 2 ).

23. The method according to claim 14 , wherein the measurement values of the inclination sensor are correlated with angular velocity values measured by a rotary rate sensor, and the current angular position is determined by an integration of the angular velocity values measured by the rotary rate sensor and the measurement values of the inclination sensor are used as reference values.

24. The method according to claim 23 , wherein the measurement values of the inclination sensor and rotary rate sensor are correlated by applying a Kalman filter algorithm to determine the angle.

25. The method according to claim 14 , wherein when determining the angle of inclination or bending angle, a temperature compensation is run based on measurement values of a temperature sensor.

Assignees

• Trumpf Maschinen Austria Gmbh & Co Kg

Inventors

• Angerer Gerhard
• Boeck Harald
• Freudenthaler Klemens
• Gaggl Josef
• Hoerl Matthias
• Schneider Bernhard
• Strasser Hagen
• Theis Helmut
• Waldherr Manfred
• Weiss Thomas

Classifications

• G01C9/02

  Details · CPC title

• B21D5/0209 Primary

  Tools therefor · CPC title

• G01B5/24 Primary

  for measuring angles or tapers; for testing the alignment of axes · CPC title

• B21D5/02

  on press brakes without making use of clamping means · CPC title

• B21D5/16

  Folding; Pleating · CPC title