US3775763A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for indicating the impending failure of a jet engine
Assignee: United States Department of the Air Force
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Filing: 1972-03-07
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Granted: 1973-11-27
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Expires: 1992-03-07
Abstract
Abstract An apparatus, for indicating impending failure of jet engines, having an electrostatic probe in the exhaust of the jet engine with the probe signal being applied to a circuit for providing pulses, at the amplitude of a signal in a sample and hold circuit, for each positive going signal followed by a negative going signal. A pulse height discriminator provides uniform output pulses, for each pulse exceeding the integrated engine noise level, and applies its output to a smoothing circuit. When the signal level in the smoothing circuit exceeds a predetermined level, a trigger circuit is operated to energize a warning circuit.
Inventors
- 👤 R Couch
- 👤 D Rossbach
- 👤 R Vopalensky
- 👤 R Fowler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:29
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/62; G01N27/626; F; F01; F01D; F01D21/00
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
103 words
An apparatus for analyzing the engine exhaust of a jet engine to indicate the presence of metal or other particles in the exhaust, comprising: an electrostatic probe positioned in the exhaust of the jet engine; means, responsive to the output signal of said probe for providing an indication of metal or other particles hitting the probe; said means, including means, for passing only pulse signals exceeding the average noise level of the probe signal by a predetermined amount; and means for indicating the presence of pulses, exceeding the average noise level of the probe signal by said predetermined amount, in the probe signal.
Claim 2
Independent Claim
103 words
An apparatus for analyzing the engine exhaust of a jet engine to indicate the presence of metal or other particles in the exhaust, comprising: an electrostatic probe positioned in the exhaust of the jet engine; means, responsive to the output signal of said probe for providing an indication of metal or other particles hitting the probe; said means, including means, for passing only pulse signals exceeding the average noise level of the probe signal by a predetermined amount; and means for indicating the presence of pulses, exceeding the average noise level of the probe signal by said predetermined amount, in the probe signal.
Claim 3
Dependent Claim
67 words
The device recited in claim 1, wherein the means, responsive to the output signal of said probe includes means for providing uniform width pulses at approximately the maximum positive signal level, for each positive going signal followed by a negative going signal; means, responsive to the last named means, for providing an output pulse for each pulse exceeding the average noise level in the probe output signal.
Claim 4
Dependent Claim
43 words
The device recited in claim 2, including an integrating circuit connected to the output of the output pulse means, and means responsive to the output of the integrating circuit for indicating when the signal level in the integrating circuit exceeds a predetermined value.
References Cited (Backward Citations)
US3221248A
Cited
US3449667A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-26 | 1977-05-28 | 1977-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-26 | 1981-05-28 | 1981-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-26 | 1985-05-28 | 1985-11-27 | $7700.00 | Window Closed / Lapsed |