Angle measuring device and method for operating an angle measuring device

Patent metadata

Field	Value
Publication number	US-11486740-B2
Application number	US-202016920348-A
Country	US
Kind code	B2
Filing date	Jul 2, 2020
Priority date	Jul 4, 2019
Publication date	Nov 1, 2022
Grant date	Nov 1, 2022

Abstract

An angle measuring device includes first and second component groups and a bearing. The first component group includes a scale element having a first graduation. The second component group has a first modular unit, including a position sensor, and a second modular unit, including first, second, and third position transducers, and a compensation coupling. The first and second modular units are connected in a torsionally stiff but axially and radially flexible manner. The angle measuring device is operable in first and second modes. In the first mode, the first graduation is scannable by the position sensor to determine a first angular position. In the second mode, the first graduation or a further graduation situated on the scale element is scannable by the position transducers to determine further angular positions. A corrected relative angular position is determinable based on the first angular position and the further angular positions.

First claim

What is claimed is:

1. An angle measuring device, comprising:
a first component group, including a scale element having a first graduation;
a second component group including a first modular unit having a first position sensor, a second modular unit having a first position transducer, a second position transducer, and a third position transducer, and a compensation coupling; and
a bearing, the first component group and the second component group rotatable relative to each other about an axis of rotation via the bearing;
wherein the position sensor and the position transducers are arranged opposite the scale element separated by an air gap;
wherein the first modular unit is connected to the second modular unit by the compensation coupling in a torsionally stiff but axially and radially flexible manner, so that the position sensor is arranged in a torsionally stiff but axially and radially flexible manner relative to the position transducers;
wherein the angle measuring device is adapted to be operated in a first mode and in a second mode;
wherein the position sensor is adapted to scan, in the first mode, the first graduation to determine a first angular position;
wherein each position transducer is adapted to scan, in the second mode, the first graduation or a further graduation provided on the scale element to determine a respective further angular position; and
wherein the angle measuring device is adapted to determine a corrected relative angular position between the first component group and the second component group based on the first angular position and the further angular positions.

2. The angle measuring device according to claim 1 , wherein the second component group includes a light source, the first graduation and the position sensor being arranged such that the relative angular position between the first component group and the second component group is optically determinable.

3. The angle measuring device according to claim 1 , wherein at least two of the position transducers are arranged at an offset under a center angle about the axis of rotation of at least 90°.

4. The angle measuring device according to claim 1 , wherein at least three position transducers are arranged along a circular line.

5. The angle measuring device according to claim 1 , wherein the scale element includes a further graduation, the first graduation being optically scannable, the further graduation being magnetically scannable.

6. The angle measuring device according to claim 1 , wherein the second component group includes a housing, the position sensor and the position transducers being arranged inside the housing.

7. The angle measuring device according to claim 1 , wherein the first position transducer, the second position transducer, and third position transducer are adapted to scan the first graduation or a further graduation provided on the scale element to determine a displacement of the scale element in a plane.

8. A method for operating an angle measuring device, as recited in claim 1 , comprising:
operating the angle measuring device in a first mode, in which the first graduation is scanned by the position sensor to determine a first angular position;
operating the angle measuring device in a second mode, in which the first graduation or a further graduation arranged on the scale element is scanned by the position transducers to determine respective further angular positions; and
determining a corrected relative angular position between the first component group and the second component group based on the first angular position and the further angular positions.

9. A method for operating an angle measuring device that includes a first component group, a second component group, and a bearing, the first component group and the second component group being rotatable relative to each other about an axis of rotation via the bearing, the first component group including a scale element having a first graduation, the second component group including a first modular unit, having a position sensor, a second modular unit, having a plurality of position transducers, and a compensation coupling, the position sensor and the position transducers being arranged opposite the scale element separated by an air gap, the first modular unit being connected to the second modular unit by the compensation coupling in a torsionally stiff but axially and radially flexible manner, so that the position sensor is arranged in a torsionally stiff but axially and radially flexible manner relative to the position transducers, comprising:
operating the angle measuring device in a first mode, in which the first graduation is scanned by the position sensor to determine a first angular position;
operating the angle measuring device in a second mode, in which the first graduation or a further graduation arranged on the scale element is scanned by the position transducers to determine respective further angular positions; and
determining a corrected relative angular position between the first component group and the second component group based on the first angular position and the further angular positions.

10. The method according to claim 9 , further comprising generating a correction value from the further angular positions determined in the second mode, wherein the correction value is used in the first mode together with the first angular position to determine the corrected relative angular position.

11. The method according to claim 9 , further comprising ascertaining and storing a correction value based on the further angular positions.

12. The method according to claim 9 , wherein, in the second mode, the scale element is rotated by at least 360° about the axis of rotation.

13. The method according to claim 9 , wherein, in the second mode, the scale element is rotated by at least 720° about the axis of rotation.

14. The method according to claim 9 , wherein the angle measuring device is sequentially operated in the first mode and in the second mode.

15. The method according to claim 9 , wherein the measuring device is simultaneously operated in the first mode and in the second mode.

16. The method according to claim 9 , further comprising:
scanning, by a first position transducer, a second position transducer, and a third position transducer, the first graduation or a further graduation provided on the scale element to determine a further angular position; and
determining a displacement of the scale element in a plane based on the determined further angular position.

17. The method according to claim 9 , wherein a fourth position transducer, a fifth position transducer, and a sixth position transducer scan a second graduation to determine an axial position of the scale element.

Assignees

• Heidenhain Gmbh Dr Johannes

Inventors

• Mitterreiter Johann
• Gruber Sebastian
• Bartlechner Alois

Classifications

• G01D5/2451

  Incremental encoders (G01D5/2454 takes precedence) · CPC title

• G01D5/3473

  Circular or rotary encoders · CPC title

• G01D5/34792

  with only digital scales or both digital and incremental scales · CPC title

• G01B7/31

  for testing the alignment of axes · CPC title

• G01D5/24485 Primary

  using other sensors · CPC title