System and method for monitoring gear and bearing health

Patent metadata

Field	Value
Publication number	US-9841352-B2
Application number	US-201514737257-A
Country	US
Kind code	B2
Filing date	Jun 11, 2015
Priority date	Jun 19, 2014
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

A method for monitoring a gear and bearing system having at least two inter-meshing gears and at least one bearing includes detecting gear and bearing vibrations with at least one vibration sensor operable to generate a signal representative of the detected gear vibrations. A carrier frequency is identified from the generated signal. A band pass filter is applied to the signal at the carrier frequency to create a filtered signal. An envelope is extracted from the filtered signal to create an extracted signal. A time-frequency analysis is then applied to the extracted signal which allows for identification of degradation of the gears.

First claim

What is claimed is:

1. A method for monitoring a system having at least one rolling element, wherein the at least one rolling element comprises at least two inter-meshing gears and/or at least one bearing, the method comprising:
detecting vibrations in the at least one rolling element with at least one vibration sensor operable to generate a signal representative of the detected vibrations in the at least one rolling element;
identifying a carrier frequency by applying a time-frequency transformation to the generated signal, wherein the step of identifying the carrier frequency includes identifying fixed frequency bands of higher amplitude response and invariant with speed across a time domain of a time-frequency representation of a ramp speed test;
applying a band pass filter at the carrier frequency to create a filtered signal;
extracting an envelope of the filtered signal to create an extracted signal;
applying time and frequency analysis to the extracted signal; and
identifying the component and degradation of the at least one rolling element based on the time frequency analysis.

2. The method of claim 1 , wherein the time-frequency transformation is a short time Fourier's transformation.

3. The method of claim 1 , wherein the at least one rolling element comprises at least two inter-meshing gears and wherein the step of identifying includes tracking a plurality of gear meshing occurrences to determine severity and magnitude of impact force.

4. The method of claim 1 , wherein the step of applying the time and frequency analysis further includes extracting a condition indicator representative of the severity and impact force of the at least one rolling element.

5. The method of claim 1 , wherein the step of applying the time and frequency analysis further includes extracting a frequency content to identify a source component of the extracted signal.

6. The method of claim 1 , wherein the at least one rolling element comprises at least two inter-meshing gears and wherein the step of identifying degradation of the gears includes comparing the extracted signal to a baseline signal.

7. The method of claim 1 , wherein the at least one rolling element comprises at least two inter-meshing gears and at least one bearing.

8. The method of claim 1 , wherein the band pass filter is a narrow band pass filter.

9. A method for monitoring a system having at least one rolling element, the at least one rolling element comprising at least two inter-meshing gears and/or at least one bearing, the method comprising:
detecting vibrations in the at least one rolling element with at least one vibration sensor operable to generate a signal representative of the detected vibrations in the at least one rolling element;
identifying a carrier frequency by applying a time-frequency transformation to the generated signal, wherein the step of identifying the carrier frequency includes identifying fixed frequency content in the time-frequency representation regardless of speed variation through a steady-state test with different speeds;
applying a band pass filter at the carrier frequency to create a filtered signal;
extracting an envelope of the filtered signal to create an extracted signal;
applying time and frequency analysis to the extracted signal; and
identifying the component and degradation of the at least one rolling element based on the time frequency analysis.

10. The method of claim 9 , wherein the at least one rolling element comprises at least two inter-meshing gears and at least one bearing.

11. The method of claim 9 , wherein the band pass filter is a narrow band pass filter.

12. The method of claim 9 , wherein the time-frequency transformation is a short time Fourier's transformation.

13. The method of claim 9 , wherein the at least one rolling element comprises at least two inter-meshing gears and wherein the step of identifying includes tracking a plurality of gear meshing occurrences to determine severity and magnitude of impact force.

14. The method of claim 9 , wherein the step of applying the time and frequency analysis further includes extracting a condition indicator representative of the severity and impact force of the at least one rolling element.

15. The method of claim 9 , wherein the step of applying the time and frequency analysis further includes extracting a frequency content to identify a source component of the extracted signal.

16. The method of claim 9 , wherein the at least one rolling element comprises at least two inter-meshing gears and wherein the step of identifying degradation of the gears includes comparing the extracted signal to a baseline signal.

Assignees

• United Technologies Corp

Inventors

• Chen Yan
• Chaudhry Zaffir A

Classifications

• G01M13/028

  Acoustic or vibration analysis · CPC title

• G01M13/045 Primary

  Acoustic or vibration analysis · CPC title