Electronic angle measuring device for a bending machine for measuring the bending angle between the legs of a metal sheet

Abstract

An electronic angle measuring device for measuring the bending angle between the legs (4) of a metal sheet (5) having a sensor element (7) which delivers angle-equivalent signals in a contact-free manner to a signal processing device (9) comprising a microprocessor and a memory unit which is connected to a digital display (10) is described. In order to create advantageous measurement conditions, it is proposed that a sensor element (7) which deflects a laser beam through a rotating mirror onto the two legs (4) of the metal sheet (5) and which forms a measured value from the reflection beam received in the emission direction, the signal processing device (9) with the microprocessor and the memory unit as well as the digital display (10) form an angle measuring device (6) which can be fastened to an upper tool (1) of a bending machine and which can be used as a manual measuring device (6).

Claims

1. An electronic angle measuring device for measuring a bending angle between two legs of a metal sheet, said device comprising: a sensor element that delivers angle-equivalent signals in a contact-free manner to a signal processing device, which has a microprocessor and a memory unit and is connected to a digital display, wherein the sensor element deflects a laser beam through a rotating mirror onto the two legs of the metal sheet and forms a measured value from a reflection beam received in an emission direction, and wherein the signal processing device with the microprocessor and the memory unit as well as the digital display form an angle measuring device; wherein said angle measuring device is fastened to an upper tool of a bending machine and is configured to be used as a manual measuring device; and wherein the tool has a gap therein and the laser passes through said gap.

2. The electronic angle measuring device according to claim 1, wherein in a housing rear wall the angle measuring device has a permanent magnet fastening to the upper tool of the bending machine.

3. The electronic angle measuring device according to claim 1, wherein the signal processing device signals that programmable tolerance limits of the angle to be measured have been exceeded or fallen below.

4. The electronic angle measuring device according to claim 1, wherein the signal processing device comprises a radio interface.

5. The electronic angle measuring device according to claim 1, wherein the angle measuring device comprises a motion sensor connected to the signal processing device, wherein said signal processing device records a lowering movement and/or a raising movement of the upper tool and triggers a measurement process.

6. The electronic angle measuring device according to claim 5, wherein the motion sensor is configured as a multiaxial acceleration sensor.

7. The electronic angle measuring device according to claim 5, wherein the signal processing device evaluates measured values stored in the memory unit during the lowering and raising movement of the upper tool so as to increase accuracy of the measured values according to mathematical methods.

8. An electronic angle measuring device for measuring a bending angle between two legs of a metal sheet, said device comprising: a sensor element that delivers angle-equivalent signals in a contact-free manner to a signal processing device, which has a microprocessor and a memory unit and is connected to a digital display, wherein the sensor element deflects a laser beam through a rotating mirror onto the two legs of the metal sheet and forms a measured value from a reflection beam received in an emission direction, and wherein the signal processing device with the microprocessor and the memory unit as well as the digital display form an angle measuring device adapted to be fastened to an upper tool of a bending machine and that is configured to be used as a manual measuring device, and wherein the angle measuring device comprises a motion sensor connected to the signal processing device, wherein said signal processing device records a lowering movement and/or a raising movement of the upper tool and triggers a measurement process.

9. The electronic angle measuring device according to claim 8, wherein the motion sensor is configured as a multiaxial acceleration sensor.

10. The electronic angle measuring device according to claim 8, wherein the signal processing device evaluates measured values stored in the memory unit during the lowering and raising movement of the upper tool so as to increase accuracy of the measured values according to mathematical methods.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The inventive subject matter is shown as an example in the drawings. In the figures

(2) FIG. 1 shows a bending machine with a digital angle measuring device according to the invention in a partially cutaway schematic side view

(3) FIG. 2 shows this bending machine in a schematic vertical section and

(4) FIG. 3 shows the electronic angle measuring device according to the invention in a simplified block diagram.

DESCRIPTION OF THE PREFERRED EMBODIMENT

(5) The bending machine shown has a lowerable and raisable upper tool 1 which cooperates with a lower tool 2 in the form of a die and is composed of stamp segments 3 arranged adjacently to one another in a row. For measurement of the bending angle between the legs 4 of a metal sheet 5 to be bent, a digital measuring device 6 is fastened to the upper tool 1, which comprises a sensor element 7 with a mirror which is rotated about an axis of rotation parallel to the apex axis of the bending angle between the two legs 4 of the metal sheet and deflects a laser beam in a plane perpendicular to the apex axis onto the two legs 4. The laser beam thereby passes through a measurement gap 8 between two stamp segments 3. Since the sensor element 7 has a receiver for the laser beam reflected in the emission direction at the legs 4 and the intensity of the reflected laser beam is highest when the laser beam is perpendicular to the legs 4, the rotational position of the mirror can be specified for the laser beams which are perpendicular to the legs 4 of the metal sheet 5, as is illustrated in FIG. 2. The respective bending angles between the two legs 4 can thus be deduced from these rotational positions of the mirror.

(6) For this purpose according to FIG. 3, the sensor element 7 is connected to a signal processing device 9 which evaluates the measurement signals received by the sensor element 7 and outputs the measured bending angles to a display 10. This display 10 is required not only for use of the angle measuring device as a hand-held device but also, when used as a machine measuring device, allows the bending angles and other displayed data to be read off without crucially looking away from the metal sheet 5 which is located in the field of view in any case.

(7) Since the angle measuring device 6 has a motion sensor 11 connected to the signal processing device 9, by recording the movement of the upper tool 1, the angle measurement can be synchronized with the movement of the upper tool 1 without needing to access the machine controller. However it is also possible to control the angle measuring device 6 synchronously to the bending process from outside, for example, by a connection of the angle measuring device 6 to the machine controller.

(8) The electronic angle measuring device 6 can be used in existing bending machines without expensive modification work if a measurement access of the sensor element 7 to the two legs 4 of the metal sheet 5 is possible which can be ensured in a simple manner with the usual composition of the upper tool 1 from stamp segments 3. The angle measuring device 6 merely needs to be suitably fastened on the upper tool 1. For this purpose it is recommended to provide at least one permanent magnet 12 in the region of the housing rear wall of the angle measuring device 6.

(9) If the motion sensor 11 is configured as a multiaxial acceleration sensor, by means of its signal for the gravitational acceleration the angle measuring device 6 can be aligned in a simple manner with respect to the horizontal apex axis of the bending angle between the two legs 4 which is predefined by the die and the stamp segments 3. In addition, it becomes possible to evaluate a measurement signal corrected with regard to the gravitational acceleration so that exclusively accelerations of the angle measuring device 6 can be used to determine the movement of the upper tool 1.

(10) If the angle measuring device 6 has a radio interface 13, data can be transmitted outwards from the angle measuring device 6 in a cableless manner but signals can also be transmitted to the angle measuring device 6 from outside. In order to be able to set different operating modes for the angle measuring device 6, the angle measuring device can also be provided with an input 14. In order to be free from cable connections, the angle measuring device 6 should preferably be fitted with batteries or rechargeable batteries 15 for the power supply.