Patent US3798626A successfully refreshed from Google Patents.
US3798626A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Foreign object impact detection in multi-bladed fluid engines
Assignee: General Electric Co
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Filing: 1972-02-28
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Granted: 1974-03-19
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Expires: 1992-02-28
Abstract
Abstract Vibrations generated by objects impacting on the blades of the rotor of the engine are sensed by an accelerometer located on the rotor bearing mount. A peak detection circuit with a suitable decay time constant is provided for detection of the peaks in the signal from the accelerometer corresponding to peaks in the vibrations from the rotor. A level detection circuit is provided responsive to a predetermined level of the detected signal to actuate suitable indication means such as an alarm.
Inventors
- 👤 B Weichbrodt
- 👤 B Darrel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:42
CPC Classifications
F; F02; F02C; F02C7/00; F02C7/04; F02C7/05
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
141 words
The combination comprising a fluid engine having a multi-bladed stator and bearing means for rotatably mounting therein a multi-bladed rotor, an accelerometer mounted on said stator adjacent said bearing means for sensing sonic frequency vibrations produced by normal engine operation and by the impact of a free object on said rotor blades, said accelerometer generating an electrical signal in accordance with said vibrations including a low amplitude signal indicative of the normal engine operation and a substantially greater amplitude signal indicative of at least a single impact of the free object on said rotor blades, peak detection circuit means coupled to said accelerometer for detecting the peak value of said object impact signal and for producing a slowly decaying output signal representative thereof, and indication means actuated by said peak detection circuit means for providing an indication of said object impact.
Claim 2
Dependent Claim
141 words
The combination comprising a fluid engine having a multi-bladed stator and bearing means for rotatably mounting therein a multi-bladed rotor, an accelerometer mounted on said stator adjacent said bearing means for sensing sonic frequency vibrations produced by normal engine operation and by the impact of a free object on said rotor blades, said accelerometer generating an electrical signal in accordance with said vibrations including a low amplitude signal indicative of the normal engine operation and a substantially greater amplitude signal indicative of at least a single impact of the free object on said rotor blades, peak detection circuit means coupled to said accelerometer for detecting the peak value of said object impact signal and for producing a slowly decaying output signal representative thereof, and indication means actuated by said peak detection circuit means for providing an indication of said object impact.
Claim 3
Dependent Claim
27 words
The combination as defined in claim 1 wherein said bearing means is a thrust bearing, and said multi-bladed rotor has a shaft extending through said thrust bearing.
Claim 4
Dependent Claim
34 words
The combination as defined in claim 1 wherein said peak detection circuit means is comprised by a parallel capacitor-resistor network having a time constant sufficiently long to enable said indication means to become operative.
Claim 5
Dependent Claim
40 words
The combination as defined in claim 3 wherein said peak detection circuit means is a voltage doubler circuit also comprised by a diode rectifier network connected across said capacitor that is conductive for either polarity of said object impact signal.
Claim 6
Dependent Claim
162 words
The combination comprising a fluid engine having a multi-bladed stator supporting a thrust bearing in which is mounted the shaft of a multi-bladed rotor, an accelerometer mounted on said stator adjacent said thrust bearing for sensing sonic frequency vibrations produced by normal engine operation and by the impact of a free object on said rotor blades, said accelerometer generating an electrical signal in accordance with said vibrations including a low amplitude signal indicative of the normal engine operation and a steeply rising, substantially greater amplitude signal indicative of at least a single impact of the free object on said rotor blades, peak detection circuit means coupled to the output of said accelerometer comprising a diode network for rectifying said accelerometer signal and a parallel capacitor-resistor network for producing a slowly decaying unidirectional output signal representative of the peak value of said object impact signal, and indication means actuated by said peak detection circuit means for providing an indication of said object impact.
Claim 7
Dependent Claim
162 words
The combination comprising a fluid engine having a multi-bladed stator supporting a thrust bearing in which is mounted the shaft of a multi-bladed rotor, an accelerometer mounted on said stator adjacent said thrust bearing for sensing sonic frequency vibrations produced by normal engine operation and by the impact of a free object on said rotor blades, said accelerometer generating an electrical signal in accordance with said vibrations including a low amplitude signal indicative of the normal engine operation and a steeply rising, substantially greater amplitude signal indicative of at least a single impact of the free object on said rotor blades, peak detection circuit means coupled to the output of said accelerometer comprising a diode network for rectifying said accelerometer signal and a parallel capacitor-resistor network for producing a slowly decaying unidirectional output signal representative of the peak value of said object impact signal, and indication means actuated by said peak detection circuit means for providing an indication of said object impact.
Claim 8
Dependent Claim
42 words
The combination as defined by claim 5 wherein said parallel capacitor-resistor network has a time constant sufficiently long to enable said indication means to become operative, and a high input impedance amplifier connected between said parallel capacitor-resistor network and said indication means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-18 | 1977-09-17 | 1978-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-18 | 1981-09-17 | 1982-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-18 | 1985-09-17 | 1986-03-19 | $7700.00 | Window Closed / Lapsed |