Patent US5146776A successfully refreshed from Google Patents.
US5146776A
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Method for continuously calibrating an optical vibration sensor
Assignee: Siemens Energy Inc
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Filing: 1990-11-26
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Granted: 1992-09-15
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Expires: 2010-11-26
Abstract
Abstract An optical vibration sensor is automatically calibrated by extracting a beat frequency vibration signal from a vibration signal produced by the optical vibration sensor, computing a resonant frequency of the optical vibration sensor using the beat frequency which has been extracted, and calibrating the optical vibration sensor based on the resonant frequency computed. The calibration method continuously compensates for changes in the resonant frequency due to temperature and mechanical changes of the optical vibration sensor. The optical vibration sensor is physically attached to an end-winding of an electrical generator.
Inventors
- 👤 Michael Twerdochlib
- 👤 Richard B. Chianese
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:51
CPC Classifications
G; G01; G01D; G01D18/00; G01D18/002; G01D18/004; G01D5/00; G01D5/26; G01D5/32; G01D5/34; G01H; G01H3/00; G01H3/005
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
83 words
A method for calibrating a vibration sensor attached to equipment, comprising the steps of: (a) obtaining a vibration signal, corresponding to vibration of the equipment, from the vibration sensor; (b) extracting a beat frequency vibration signal having a beat frequency from the vibration signal obtained in step (a); (c) computing a resonant frequency of the vibration sensor in dependence upon the beat frequency extracted in step (b); and (d) calibrating the vibration sensor in dependence upon the resonant frequency computed in step (c).
Claim 2
Independent Claim
83 words
A method for calibrating a vibration sensor attached to equipment, comprising the steps of: (a) obtaining a vibration signal, corresponding to vibration of the equipment, from the vibration sensor; (b) extracting a beat frequency vibration signal having a beat frequency from the vibration signal obtained in step (a); (c) computing a resonant frequency of the vibration sensor in dependence upon the beat frequency extracted in step (b); and (d) calibrating the vibration sensor in dependence upon the resonant frequency computed in step (c).
Claim 3
Dependent Claim
38 words
A method as recited in claim 1, wherein the vibration signal obtained in step (a) includes partial pulses, and wherein said extracting in step (b) comprises the step of calculating the beat frequency based on the partial pulses.
Claim 4
Dependent Claim
53 words
A method as recited in claim 1, wherein the equipment is an electrical generator having a 120 Hz end-turn vibration, and wherein the vibration signal obtained in step (a) includes a mechanical vibration signal resulting from the 120 Hz end-turn vibration of the electrical generator and the resonant frequency of the vibration sensor.
Claim 5
Dependent Claim
84 words
A method as recited in claim 1, wherein the vibration sensor is an optical vibration sensor having a grid assembly having a plurality of grids separated by slits, wherein said obtaining in step (a) comprises the steps of: (a1) passing a light beam through the grids of the grid assembly; (a2) vibrating the grid assembly in accordance with the vibration of the equipment; (a3) producing light pulses corresponding to the vibration of the equipment; and (a4) converting the light pulses into the vibration signal.
Claim 6
Dependent Claim
22 words
A method as recited in claim 4, wherein the equipment is a generator, and wherein the vibration signal is an electrical signal.
Claim 7
Dependent Claim
76 words
A method as recited in claim 4, wherein the light pulses produced in step (a3) include full slit passage pulses and partial slit passage pulses, and wherein said extracting in step (b) comprises the steps of: (b1) detecting a plurality of the partial slit passage pulses; (b2) extracting data points from the vibration signal corresponding to the partial slit passage pulses detected in step (b1); and (b3) calculating the beat frequency based on the data points.
Claim 8
Dependent Claim
53 words
A method as recited in claim 6, wherein the equipment is an electrical generator having a 120 Hz end-turn vibration, and wherein the vibration signal obtained in step (a) includes a mechanical vibration signal resulting from the 120 Hz end-turn vibration of the electrical generator and the resonant frequency of the vibration sensor.
Claim 9
Dependent Claim
81 words
A vibration sensing system for equipment, comprising: vibration sensor means, attached to the equipment, for producing a vibration signal in dependence upon vibration of the equipment; and control means for calibrating said vibration sensor means by extracting a beat frequency vibration signal having a beat frequency from the vibration signal produced by said vibration sensor means, computing a resonant frequency of said vibration sensor means in dependence upon the beat frequency, and calibrating the vibration sensor based on the resonant frequency.
Claim 10
Dependent Claim
81 words
A vibration sensing system for equipment, comprising: vibration sensor means, attached to the equipment, for producing a vibration signal in dependence upon vibration of the equipment; and control means for calibrating said vibration sensor means by extracting a beat frequency vibration signal having a beat frequency from the vibration signal produced by said vibration sensor means, computing a resonant frequency of said vibration sensor means in dependence upon the beat frequency, and calibrating the vibration sensor based on the resonant frequency.
Claim 11
Dependent Claim
49 words
A system as recited in claim 8, wherein the equipment is an electrical generator having a 120 Hz end-turn vibration, and wherein the vibration signal includes a mechanical vibration signal resulting from the 120 Hz end-turn vibration of the electrical generator and the resonant frequency of the vibration sensor.
Claim 12
Dependent Claim
39 words
A system as recited in claim 8, wherein said vibration sensor means comprises: pulse generating means for producing light pulses corresponding to the vibration of the equipment; and conversion means for converting the light pulses into the vibration signal.
Claim 13
Dependent Claim
86 words
A system as recited in claim 10, wherein the light pulses produced by said pulse generating means include full slit passage pulses and partial slit passage pulses, and wherein said control means comprises: partial pulse detecting means for detecting a plurality of the partial slit passage pulses; data point extracting means for extracting data points from the vibration signal corresponding to the partial slit passage pulses detected by said detection means; and beat frequency calculation means for calculating the beat frequency based on the data points.
Claim 14
Dependent Claim
24 words
A system as recited in claim 11, wherein said pulse generating means includes a grid assembly having a plurality of grids separated by slits.
Claim 15
Dependent Claim
20 words
A system as recited in claim 11, wherein the predetermined vibration frequency is one of 120 Hz and 100 Hz.
Claim 16
Dependent Claim
36 words
A system as recited in claim 11, wherein the equipment is an electrical generator, the electrical generator producing an electrical signal of a standard cycle, and wherein the vibration sensor means is an optical vibration sensor.
Claim 17
Dependent Claim
49 words
A system as recited in claim 11, wherein the equipment is an electrical generator having a 120 Hz end-turn vibration, and wherein the vibration signal includes a mechanical vibration signal resulting from the 120 Hz end-turn vibration of the electrical generator and the resonant frequency of the vibration sensor.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-09-15 | 1996-03-16 | 1996-09-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-09-15 | 2000-03-16 | 2000-09-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-09-15 | 2004-03-16 | 2004-09-15 | $7700.00 | Window Closed / Lapsed |