Patent US3654807A successfully refreshed from Google Patents.
US3654807A
Expired / Lapsed
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Angle of attack indicating system
Assignee: Individual
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Filing: 1970-01-30
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Granted: 1972-04-11
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Expires: 1990-01-30
Abstract
Abstract An electronic angle of attack indicating system is provided which may be used, for example, to indicate the sail trim of a sailboat, or the angle of attack of an aircraft, or the like, so that the sail or the aircraft may be maintained at any preset attack angle. The system of the invention uses a pair of temperature sensitive devices, such as thermistors, which are mounted on either side of the leading edge of an airfoil, such as a sail or wing, and which sense the air flow differential on the opposite sides of the airfoil, by virtue of the resulting temperature differences. An electric indicating system coupled to the temperature sensitive devices indicates the existence of the air flow differential, so that the appropriate adjustments may be made to maintain the preset attack angle.
Inventors
- 👤 Donald Stephen Deskey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:00
CPC Classifications
G; G01; G01P; G01P5/00; G01P5/10; G01P5/12; B; B63; B63B; B63B49/00
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
188 words
A system for sensing deviations of a fluid foil from a predetermined attack angle with respect to the fluid through which the foil is moving, said system including: first and second sensors mounted on the foil on opposite sides thereof and responsive to the fluid stream over the respective surfaces of said foil for providing electrical indications thereof; electrical circuit means connected to said sensors for developing electrical output signals whenever the fluid flow differential over the respective surfaces of said foil departs from an optimum range; said electrical circuit means including a differential amplifier connected to said sensors for developing electrical output signals having an amplitude related to the differential between the electrical indications provided by said first and second sensors, and multivibrator networks connected to said differential amplifier and responding to the output signals from said differential amplifier to be triggered thereby and indicate the direction and amount of the aforesaid deviations of said foil from said predetermined attack angle; and utilization circuitry coupled to said electrical circuit means for developing a predetermined control effect in response to said electrical output from said electrical circuit means.
Claim 2
Independent Claim
188 words
A system for sensing deviations of a fluid foil from a predetermined attack angle with respect to the fluid through which the foil is moving, said system including: first and second sensors mounted on the foil on opposite sides thereof and responsive to the fluid stream over the respective surfaces of said foil for providing electrical indications thereof; electrical circuit means connected to said sensors for developing electrical output signals whenever the fluid flow differential over the respective surfaces of said foil departs from an optimum range; said electrical circuit means including a differential amplifier connected to said sensors for developing electrical output signals having an amplitude related to the differential between the electrical indications provided by said first and second sensors, and multivibrator networks connected to said differential amplifier and responding to the output signals from said differential amplifier to be triggered thereby and indicate the direction and amount of the aforesaid deviations of said foil from said predetermined attack angle; and utilization circuitry coupled to said electrical circuit means for developing a predetermined control effect in response to said electrical output from said electrical circuit means.
Claim 3
Dependent Claim
24 words
The system defined in claim 1, in which said utilization circuitry includes indicator lamps connected to said multivibrator circuits to be selectively controlled thereby.
Claim 4
Independent Claim
168 words
A system for sensing deviations, from a predetermined attack angle, of the sail of a sailboat which may be sailed on a port or starboard tack, including: first and second sensors mounted on the sail on opposite sides thereof and responsive to the air stream over the respective surfaces of said sail for providing electrical indications thereof; electrical circuit means connected to said sensors for developing electrical output signals whenever the fluid flow differential over the respective surfaces of said sail departs from an optimum range; and utilization circuitry coupled to said electrical circuit means for developing a predetermined control effect in response to said electrical output from said electrical circuit means, said utilization circuitry including a first section for developing said predetermined control effect during said port tack and a second section for developing said predetermined control effect during said starboard tack, and further including selection switching means for conditioning said electrical circuit means and said utilization circuitry selectively for said port tack and said starboard tack.
Claim 5
Independent Claim
168 words
A system for sensing deviations, from a predetermined attack angle, of the sail of a sailboat which may be sailed on a port or starboard tack, including: first and second sensors mounted on the sail on opposite sides thereof and responsive to the air stream over the respective surfaces of said sail for providing electrical indications thereof; electrical circuit means connected to said sensors for developing electrical output signals whenever the fluid flow differential over the respective surfaces of said sail departs from an optimum range; and utilization circuitry coupled to said electrical circuit means for developing a predetermined control effect in response to said electrical output from said electrical circuit means, said utilization circuitry including a first section for developing said predetermined control effect during said port tack and a second section for developing said predetermined control effect during said starboard tack, and further including selection switching means for conditioning said electrical circuit means and said utilization circuitry selectively for said port tack and said starboard tack.
Claim 6
Dependent Claim
47 words
The system defined in claim 3, in which said utilization circuitry includes a pair of indicator lights connected to be selectively energized during the port tack in accordance with a first parameter, and to be seleCtively energized during the starboard tack in accordance with a second parameter.
Claim 7
Dependent Claim
18 words
The system defined in claim 4, in which said indicator lights are located on a single control panel.
Claim 8
Dependent Claim
32 words
The system defined in claim 4, in which said utilization circuitry includes a further pair of indicator lights respectively connected in shunt with said first-mentioned pair and located on a second panel.
References Cited (Backward Citations)
US2512278A
Cited
US3304778A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-11 | 1975-10-11 | 1976-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-11 | 1979-10-11 | 1980-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-11 | 1983-10-11 | 1984-04-11 | $7700.00 | Window Closed / Lapsed |