Patent US3736796A successfully refreshed from Google Patents.
US3736796A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fan engine thrust monitor
Assignee: Avco Corp
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Filing: 1972-03-27
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Granted: 1973-06-05
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Expires: 1992-03-27
Abstract
Abstract A warning signal is generated if a high bypass ratio fan-type gas turbine engine fails to develop adequate thrust for takeoff of an aircraft. Two engine operating parameters are derived, referred compressor speed and referred fan speed. After a takeoff is initiated, a warning signal is developed under any one of three conditions: (1) if the referred compressor speed is less than a pre-established reference level; (2) if the referred fan speed is less than a pre-established reference level; and (3) if the ratio of compressor speed to fan speed is less than a preestablished reference level.
Inventors
- 👤 R Hohenberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:28
CPC Classifications
G; G05; G05D; G05D1/00; G05D1/0083
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
142 words
In a warning system for use with a high bypass ratio fan-type engine during takeoff, a pilot warning system comprising: means for generating a first speed signal proportional to the referred compressor speed of said engine; a first reference source having a predetermined first reference level; means when said first speed signal is above said level for generating a first logic signal; means for generating a second speed signal proportional to the referred fan speed of said engine; a second reference source having a predetermined second reference level; means when said first speed signal is above said level for generating a second logic signal; an initially disabled logic circuit, when enabled said logic circuit developing a warning signal in the absence of either of said first and second logic signals; and means for enabling said logic circuit after a predetermined time period.
Claim 2
Dependent Claim
142 words
In a warning system for use with a high bypass ratio fan-type engine during takeoff, a pilot warning system comprising: means for generating a first speed signal proportional to the referred compressor speed of said engine; a first reference source having a predetermined first reference level; means when said first speed signal is above said level for generating a first logic signal; means for generating a second speed signal proportional to the referred fan speed of said engine; a second reference source having a predetermined second reference level; means when said first speed signal is above said level for generating a second logic signal; an initially disabled logic circuit, when enabled said logic circuit developing a warning signal in the absence of either of said first and second logic signals; and means for enabling said logic circuit after a predetermined time period.
Claim 3
Dependent Claim
55 words
The invention as defined in claim 1 wherein said means for enabling said logic circuit comprises the output of a time delay circuit; and an AND gate initiated in response to the simultaneous application of a plurality of condition responsive signals, the output of said AND gate initiating the operatIon of said time delay circuit.
Claim 4
Dependent Claim
94 words
The invention as defined in claim 1, and means for generating a third speed signal proportional to compressor speed; means for generating a fourth speed signal proportional to fan speed; means for generating a third logic signal proportional to the ratio of said third speed signal to said fourth speed signal; a third reference source having a predetermined third reference level; means when said third logic signal deviates from said third reference level for generating a third logic signal, said third logic signal being applied to said logic circuit to modify said warning signal.
Claim 5
Dependent Claim
55 words
The invention as defined in claim 3 wherein said means for enabling said logic circuit comprises the output of a time delay circuit; and an AND gate initiated in response to the simultaneous application of a plurality of condition responsive signals, the output of said AND gate initiating the operation of said time delay circuit.
Claim 6
Dependent Claim
33 words
The invention as defined in claim 4 wherein said condition responsive signals comprise a signal responsive to throttle position, a signal responsive to landing gear position and a signal responsive to air speed.
References Cited (Backward Citations)
US3338050A
Cited
US3678742A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-04 | 1976-12-04 | 1977-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-04 | 1980-12-04 | 1981-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-04 | 1984-12-04 | 1985-06-05 | $7700.00 | Window Closed / Lapsed |