Arrangement and method for measuring the deformation of a shaft

• US 8,610,890 B2
• Filed: 01/27/2012
• Issued: 12/17/2013
• Est. Priority Date: 02/01/2011
• Status: Active Grant

• Current Assignee: General Electric Technology GmbH (GE Aerospace)
• Original Assignee: Alstom Technology Ltd. (Alstom SA)
• Inventors: Hemsley, Philip David
• Primary Examiner(s): PHAM, HOA Q
• Application Number:
  US13/359,501
• Publication Number:
  US 20120194825A1
• Time in Patent Office: 690 Days
• Field of Search: 3562371-2375, 356/35.5, 235/462.25, 359/224.1
• US Class Current: 356/237.1
• CPC Class Codes: G01L 3/12 involving photoelectric means

Abstract

A method for measuring deformation of a shaft by a device includes illuminating a pattern applied on the shaft before the deformation is applied; and detecting a first reference position by detecting the radiation reflected by the pattern, after the deformation is applied illuminating the pattern and detecting a second reference position by detecting the radiation reflected by the pattern. Based on the distance between the first and the second reference positions, the shaft circumferential deformation and/or torque is determined.

Claims

1. Arrangement of a shaft with a device for measuring a deformation thereof, the device comprising:

a curved pattern applied on the shaft;

a radiation source for illuminating the pattern,

a sensor for detecting the radiation reflected by the pattern, and

a carrier movable in a predefined direction to the shaft axis over a zone facing the pattern, wherein the carrier carries at least the sensor.

2. The arrangement according to claim 1, wherein the carrier also carries the radiation source.

3. The arrangement according to claim 1, wherein the predefined direction is a direction substantially parallel to the shaft axis.

4. The arrangement according to claim 1, wherein the curved pattern together with an axis parallel to the shaft axis defines angles that change over the curved pattern.

5. The arrangement according to claim 1, further comprising a sensor, which senses an axial position of the shaft.

6. The arrangement according to claim 1, further comprising a control unit, which activates the radiation source only when the pattern faces the radiation source.

7. The arrangement according to claim 6, further comprising an angle sensor associated with the shaft and connected to the control unit.

8. The arrangement according to claim 1, wherein the radiation source is a light source.

9. The arrangement according to claim 8, wherein the light source is a laser.

10. The arrangement according to claim 1, wherein the pattern comprises a plurality of discrete angled lines.

11. Method for measuring a deformation of a shaft using a device comprising:

a curved pattern applied on the shaft;

a radiation source for illuminating the pattern,

a sensor for detecting the radiation reflected by the pattern,

a carrier movable in a predefined direction to the shaft axis over a zone facing the pattern, wherein the carrier carries at least the sensor;

or the sensor includes a plurality of sensors that define an array that extends over a zone facing the pattern, the method comprising;

illuminating the pattern, before deformation;

detecting a first reference position by detecting the radiation reflected by the pattern;

illuminating the pattern, after deformation;

detecting a second reference position by detecting the radiation reflected by the pattern; and

determining the shaft circumferential deformation and/or torque based on a distance between the first and the second reference positions.

12. The method according to claim 11, wherein the carrier also carries the radiation source.

13. The method according to claim 11, wherein the distance between the first and the second reference positions is ascertained along a direction parallel to a shaft axis.

14. The method according to claim 11, wherein the array also comprises a plurality of radiation sources.