Non-contact strain measurement

Patent metadata

Field	Value
Publication number	US-2016161242-A1
Application number	US-201414903919-A
Country	US
Kind code	A1
Filing date	Jul 9, 2014
Priority date	Jul 9, 2013
Publication date	Jun 9, 2016
Grant date	—

Abstract

Non-contact strain measurement systems and their method of use to detect strain on rotating components are disclosed. A non-contact strain measurement system comprises magnetic materials plated onto a rotatable component in addition to appropriate encoders and controller. The magnetic materials are spaced apart a first distance D 1 when the component is not rotating, and a second distance D 2 when the component is rotating. The encoders and controller are utilized to detect strain on the rotating component. A method of using the system to detect strain on a rotating component includes detecting the first distance D 1 then detecting the second distance D 2 , and calculating the strain imparted onto the component from a difference between D 1 and D 2 .

First claim

What is claimed is:

1 . A system for measuring strain imparted to a rotating component, the system comprising:
a first magnetic target plated onto the component at a first initial position; a first encoder for detecting a first actual position of the first magnetic target when the component is rotating; a second magnetic target plated onto the component at a second initial position; a second encoder for detecting a second actual position of the second magnetic target when the component is rotating; the first and second initial positions being spaced apart by a first distance D 1 when the component is not rotating; the first and second actual positions being spaced apart by a second distance D 2 when the component is rotating at a rotational velocity sufficient to impart a measurable strain to the component; a controller for receiving first and second signals from the first and second encoders respectively indicative of the first and second actual positions respectively, the controller having a memory programmed to calculate D 2 from the first and second signals and to calculate strain imparted onto the component from a difference between D 2 and D 1 .

2 . The system of claim 1 wherein the first and second encoders are integrated together in a single housing.

3 . The system of claim 1 wherein the first and second encoders and the controller are integrated together in a single housing.

4 . The system of claim 1 wherein the first and second targets are electroplated onto the component.

5 . The system of claim 1 wherein the first and second targets are electroless plated onto the component.

6 . The system of claim 1 wherein the first and second targets have thicknesses ranging from about 2.5 to about 20 microns.

7 . The system of claim 1 wherein the first encoder includes a Hall effect sensor.

8 . The system of claim 1 wherein the second encoder includes a Hall effect sensor.

9 . The system of claim 1 wherein the first and second encoders include Hall effect sensors.

10 . The system of claim 1 wherein the first and second targets may be removed from the component by peeling.

11 . A system for measuring strain imparted to a fan blade assembly, the system comprising:
a first magnetic target plated onto the fan blade assembly at a first initial position; a first encoder for detecting a first actual position of the first magnetic target when the fan blade assembly is rotating; a second magnetic target plated onto the fan blade assembly at a second initial position; a second encoder for detecting a second actual position of the second magnetic target when the fan blade assembly is rotating; the first and second initial positions being spaced apart by a first distance D 1 when the fan blade assembly is not rotating; the first and second actual positions being spaced apart by a second distance D 2 when the fan blade assembly is rotating at a rotational velocity sufficient to impart a measurable strain to the fan blade assembly; a controller for receiving first and second signals from the first and second encoders respectively indicative of the first and second actual positions respectively, the controller having a memory programmed to calculate D 2 from the first and second signals and to calculate strain imparted onto the fan blade assembly from a difference between D 2 and D 1 .

11 . The system of claim 11 wherein the first and second targets are electroplated onto the component.

12 . The system of claim 11 wherein the first and second targets are electroless plated onto the component.

13 . The system of claim 11 wherein the first and second targets have thicknesses ranging from about 2.5 to about 20 microns.

14 . The system of claim 11 wherein the first encoder includes a Hall effect sensor.

15 . The system of claim 11 wherein the second encoder includes a Hall effect sensor.

16 . The system of claim 11 wherein the first and second encoders include Hall effect sensors.

17 . A method for detecting strain imparted to a rotating component, the method comprising:
plating a first magnetic target onto the component at a first initial position; plating a second magnetic target onto the component at a second initial position that is spaced apart from the first initial position by a first distance D 1 ; detecting a first actual position of the first magnetic target when the component is rotating; detecting a second actual position of the second magnetic target when the component is rotating; calculating a second distance D 2 between the first and second actual positions when the component is rotating; calculating strain imparted onto the component from a difference between D 1 and D 2 .

18 . The method of claim 11 wherein the first and second targets are electroplated onto the component.

19 . The method of claim 11 wherein the first and second targets are electroless plated onto the component.

20 . The method of claim 11 wherein the first and second targets have thicknesses ranging from about 2.5 to about 20 microns.

Assignees

• United Technologies Corp

Inventors

• Cook Grant O
• Twelves Wendell V

Classifications

• B33Y10/00

  Processes of additive manufacturing · CPC title

• G01D5/12

  using electric or magnetic means (G01D5/06 takes precedence) · CPC title

• B29K2105/12

  of short lengths, e.g. chopped filaments, staple fibres or bristles · CPC title

• B32B2250/02

  2 layers · CPC title

• C25D7/04

  Tubes; Rings; Hollow bodies · CPC title