Patent US4034334A successfully refreshed from Google Patents.
US4034334A
Expired / Lapsed
US
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Airfoil position range selecting, indicating and warning system for an aircraft
Assignee: Boeing Co
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Filing: 1975-07-14
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Granted: 1977-07-05
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Expires: 1995-07-14
Abstract
Abstract To assure takeoff controllability of aircraft of the type having movably mounted stabilizers, a plurality of different stabilizer position ranges are established, any one of which may be selected by a range selector switch operated by the pilot. Proper pilot selection of an available stabilizer range depends on the gross weight and the location of the center of gravity of the loaded aircraft. This dependency is automatically accounted for by sensing the amount of load on the nose landing gear, by means of a pressure sensitive switch associated with the nose gear shock strut. The condition of the pressure switch indicates the proper range of stabilizer positions as a function of the gross weight and location of the aircraft's center of gravity. Circuit means compare the condition of the pressure switch with the position of the range selector switch and a range warning indicator is actuated if the nose loading requires a different stabilizer range. In another embodiment, the pressure sensitive switch is connected to a stabilizer range selector circuit for automatically selecting the proper range.
Inventors
- 👤 Donald Cooper Allyn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:25
CPC Classifications
G; G01; G01M; G01M1/00; G01M1/12; G01M1/122; G01M1/125; G05; G05D; G05D1/00; G05D1/08; G05D1/0808; G05D1/0816
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
169 words
A position range selection and warning apparatus for a positionable airfoil of an aircraft comprising: airfoil position indicator means for displaying the position of an airfoil; range indicator means associated with said position indicator means and having first and second indicating states defining different, predetermined ranges of airfoil positions; selector switch means connected to said range indicator means and having first and second positions, said range indicator means being responsive to said switch means to alternatively assume said first and second indicating states when said switch means is in said first and second positions respectively; load sensing means associated with a landing gear that is located adjacent one end of the aircraft fuselage for producing a signal indicative of a load supported by such landing gear; and warning indicator means connected to said load sensing means and to said selector switch means and being responsive to a predetermined relationship between said signal produced by said sensing means and the positions of said switch means to produce a warning indication.
Claim 2
Dependent Claim
169 words
A position range selection and warning apparatus for a positionable airfoil of an aircraft comprising: airfoil position indicator means for displaying the position of an airfoil; range indicator means associated with said position indicator means and having first and second indicating states defining different, predetermined ranges of airfoil positions; selector switch means connected to said range indicator means and having first and second positions, said range indicator means being responsive to said switch means to alternatively assume said first and second indicating states when said switch means is in said first and second positions respectively; load sensing means associated with a landing gear that is located adjacent one end of the aircraft fuselage for producing a signal indicative of a load supported by such landing gear; and warning indicator means connected to said load sensing means and to said selector switch means and being responsive to a predetermined relationship between said signal produced by said sensing means and the positions of said switch means to produce a warning indication.
Claim 3
Dependent Claim
106 words
The apparatus set forth in claim 1, further comprising: additional warning indicator means; and position limit switch means responsive to the position of said airfoil and defining first and second sets of position limits matching said ranges, said limit switch means being connected to said selector switch means and to said additional warning indicator means for activating said additional warning indicator means when said switch means is in said first position and the airfoil is positioned outside of said first set of position limits and when said switch means is in said second position and the airfoil is positioned outside said second set of position limits.
Claim 4
Dependent Claim
50 words
The apparatus set forth in claim 1, wherein said range indicator means includes a plurality of selectively energizable lamps disposed adjacent said airfoil position indicator means and in which different ones of said lamps are energized in accordance with said first and second indicating states to indicate said predetermined ranges.
Claim 5
Dependent Claim
40 words
The apparatus of claim 1, wherein said landing gear includes a shock absorber having an internal fluid pressure representative of said load, and said load sensing means includes a pressure sensitive switch that is responsive to said internal fluid pressure.
Claim 6
Dependent Claim
76 words
The apparatus set forth in claim 1, further including a circuit means connecting said load sensing means and selector switch means to said warning indicator means, said circuit means including an electrical delay means for delaying said signal from said sensing means so that said warning indicator means is responsive to said predetermined relationship between said signal produced by said sensing means as delayed by said delay means and the position of said selector switch means.
Claim 7
Dependent Claim
55 words
The apparatus set forth in claim 1, wherein said predetermined ranges defined by said first and second states of said range indicator means overlap at a mid region of said airfoil position indicator means, and said range indicator means includes a third indicating state defining an additional, predetermined mid band range where said overlap occurs.
Claim 8
Dependent Claim
175 words
The apparatus set forth in claim 6, wherein said selector switch means includes a third position, said range indicator means being responsive to said switch means to assume said third state when said switch means is in said third position, said load sensing means including switching means having first and second conditions and assuming said first condition in response to a load supported by said landing gear that is in excess of a predetermined magnitude and assuming said second condition in response to a load supported by said landing gear that is less than said predetermined magnitude, and said warning indicator means being responsive to said selector switch means in its first position when said switching means of said load sensing means is in its first condition, and being responsive to said selector switch means in its second position when said switching means of said load sensing means is in its second condition, and said warning indicator means being nonresponsive to said load sensing means when said selector switch means is in its third position.
Claim 9
Dependent Claim
182 words
The apparatus set forth in claim 6, further comprising: additional warning indicator means; and position limit switch means responsive to the position of said airfoil and defining first, second and third sets of position limits respectively matching said predetermined ranges of airfoil positions, said selector switch means further including a third position to which said range indicator means is responsive so as to assume said third indicating state and in which the first mentioned said warning indicator means is non-responsive to said predetermined relationship, and said selector switch means further including means for selectively connecting said position limit switch means to said additional warning indicator means for activating said additional warning indicator means when said selector switch means is in its first position and the airfoil is positioned outside of said first set of position limits and when said selector switch means is in its second position and said airfoil is positioned outside said second set of position limits and when said selector switch means is in its third position and said airfoil is positioned outside said third set of position limits.
Claim 10
Dependent Claim
151 words
An airfoil position range selection and warning method for an aircraft having a positionable airfoil compising: indicating the position of the airfoil on a visual indicator; selecting one of a plurality of different, predetermined ranges of allowable airfoil positions by disposing a selector switch in one of a plurality of alternative positions; visually indicating the selected range adjacent the visual indicator of the airfoil position in accordance with the position of said selector switch; sensing a load that is supported by a landing gear in which the landing gear is located adjacent one end of the aircraft fuselage, and developing an electrical signal indicative of such load; producing a warning indication in response to the occurrence of a predetermined relationship between the step of selecting one of said ranges as determined by the position of said selector switch and the step of sensing said load as indicated by said electrical signal.
Claim 11
Dependent Claim
151 words
An airfoil position range selection and warning method for an aircraft having a positionable airfoil compising: indicating the position of the airfoil on a visual indicator; selecting one of a plurality of different, predetermined ranges of allowable airfoil positions by disposing a selector switch in one of a plurality of alternative positions; visually indicating the selected range adjacent the visual indicator of the airfoil position in accordance with the position of said selector switch; sensing a load that is supported by a landing gear in which the landing gear is located adjacent one end of the aircraft fuselage, and developing an electrical signal indicative of such load; producing a warning indication in response to the occurrence of a predetermined relationship between the step of selecting one of said ranges as determined by the position of said selector switch and the step of sensing said load as indicated by said electrical signal.
Claim 12
Dependent Claim
86 words
The method of claim 9, further including the steps of: mounting a plurality of sets of limit switches for actuation by the airfoil at positions thereof matching the limits of the respective said plurality of predetermined ranges; selecting different sets of said limit switches for operating an additional warning indicator in which the selected sets depend on the position of said selector switch; and electrically activating such additional warning indicator when the position of the airfoil exceeds the limits of the selected set of limit switches.
Claim 13
Independent Claim
145 words
An apparatus for automatically setting range limits of a positionable airfoil of an aircraft comprising: load sensing means mountable on an aircraft for sensing a load supported by a landing gear in which such landing gear is located adjacent one end of the fuselage; limit switch means mountable on the aircraft for defining first and second sets of switching point position limits associated with different, predetermined ranges of airfoil positions, said limit switch means connected to said load sensing means for selectively, alternatively enabling said first and second sets of switching point position limits of said switch means depending on the load sensed by said load sensing means; and warning indicator means connected to said limit switch means for producing a warning indication in response to the airfoil being positioned outside of the set of switching point position limits enabled by said load sensing means.
Claim 14
Independent Claim
145 words
An apparatus for automatically setting range limits of a positionable airfoil of an aircraft comprising: load sensing means mountable on an aircraft for sensing a load supported by a landing gear in which such landing gear is located adjacent one end of the fuselage; limit switch means mountable on the aircraft for defining first and second sets of switching point position limits associated with different, predetermined ranges of airfoil positions, said limit switch means connected to said load sensing means for selectively, alternatively enabling said first and second sets of switching point position limits of said switch means depending on the load sensed by said load sensing means; and warning indicator means connected to said limit switch means for producing a warning indication in response to the airfoil being positioned outside of the set of switching point position limits enabled by said load sensing means.
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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) | 1980-07-04 | 1981-01-03 | 1981-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-04 | 1985-01-03 | 1985-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-04 | 1989-01-03 | 1989-07-05 | $7700.00 | Window Closed / Lapsed |