Patent US3885759A successfully refreshed from Google Patents.
US3885759A
Expired / Lapsed
US
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Nose wheel steering system
Assignee: Lear Avia Corp
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Filing: 1973-06-21
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Granted: 1975-05-27
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Expires: 1993-06-21
Abstract
Abstract Smooth and safe turning of the aircraft is insured while it is taxied along the ground. Sizable planes can be controlled therewith, including business jets and airliners. Unintentional abrupt turns are prevented by the control system hereof. A variable authority command supersedes the pilot''s own steering command. The authority signal is a function of both the plane''s concurrent ground speed and the degree of the pilot''s command. Wider latitude of steering is permitted by the system at the lower ground speeds, as + OR - 45* when below 10 knots; tapering off to a tighter latitude, as to only + OR - 5* when above 45 knots.
Inventors
- 👤 William P Lear
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:32
CPC Classifications
B; B64; B64C; B64C25/00; B64C25/32; B64C25/50; B64C25/505; G; G05; G05D; G05D1/00; G05D1/0083
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
208 words
A steering system for an aircraft having a pilot steering command member and a nose wheel that effects steering of the aircraft on the ground, comprising first transducer means coupled to the command member for generating an a.c. signal (Rc) that corresponds in phase and magnitude to the steering command of the pilot on the member, generating means of plural signals (Vn) that correspond to the ground speed of the aircraft, multiplier means including an individual multiplier unit for each of said (Vn) signals to provide n resultant signals (En) each of which corresponds to Rc.(1/Vn) respectively, a voting circuit with a section connected to each En signal, said voting circuit selecting as its output the mid-value (Em) of the (En) signals, second transducer means coupled to the nose wheel for generating an a.c. signal (Nc) that corresponds in phase and magnitude to the angular position of the nose wheel, circuit means responsive to said (Em) and (Nc) signals to provide a net servomotor control signal, and servomotor means mechanically coupled to the nose wheel and in circuit connection with said circuit means whereby the nose wheel is angularly positionable for steering the aircraft within a predetermined variable authority command range that corresponds to the elected (Em) signal.
Claim 2
Dependent Claim
208 words
A steering system for an aircraft having a pilot steering command member and a nose wheel that effects steering of the aircraft on the ground, comprising first transducer means coupled to the command member for generating an a.c. signal (Rc) that corresponds in phase and magnitude to the steering command of the pilot on the member, generating means of plural signals (Vn) that correspond to the ground speed of the aircraft, multiplier means including an individual multiplier unit for each of said (Vn) signals to provide n resultant signals (En) each of which corresponds to Rc.(1/Vn) respectively, a voting circuit with a section connected to each En signal, said voting circuit selecting as its output the mid-value (Em) of the (En) signals, second transducer means coupled to the nose wheel for generating an a.c. signal (Nc) that corresponds in phase and magnitude to the angular position of the nose wheel, circuit means responsive to said (Em) and (Nc) signals to provide a net servomotor control signal, and servomotor means mechanically coupled to the nose wheel and in circuit connection with said circuit means whereby the nose wheel is angularly positionable for steering the aircraft within a predetermined variable authority command range that corresponds to the elected (Em) signal.
Claim 3
Dependent Claim
49 words
A steering system for an aircraft as claimed in claim 1, in which said multiplier units are proportioned to provide said variable authority command range with wider steering latitude made available at the lower ground speeds, which range tapers off to a tighter latitude at the higher ground speeds.
Claim 4
Dependent Claim
61 words
A steering system for an aircraft as claimed in claim 2, in which a steering latitude range of the order of + or - 45* is thereby made available at ground speeds below 10 knots, which range is tapered down to a steering latitude of the order of + or - 5* when the aircraft ground speed is above 45 knots.
Claim 5
Dependent Claim
73 words
A steering system for an aircraft as claimed in claim 3, in which said ground speed generating means are wheel generators that provide corresponding a.c. signals (Vn) at respective frequencies that correspond to the ground speed of the aircraft, and said multiplier units are of the pulse width modulation type arranged with a duty cycle that increases with the frequency of (Vn) thereby effecting the gain (K) of each (Vn) in inverse relation.
Claim 6
Dependent Claim
73 words
A steering system for an aircraft as claimed in claim 1, in which said ground speed generating means are wheel generators that provide corresponding a.c. signals (Vn) at respective frequencies that correspond to the ground speed of the aircraft, and said multiplier units are of the pulse width modulation type arranged with a duty cycle that increases with the frequency of (Vn) thereby effecting the gain (K) of each (Vn) in inverse relation.
Claim 7
Dependent Claim
68 words
A steering system for an aircraft as claimed in claim 5, in which the a.c. nose wheel angular follow-up signal (Nc) is connected into said circuit means in opposite phase relation to that of the pilot command signal (Rc) thereat and provide a final control signal (Cs) to said servomotor means whereby its deflection of the nose wheel is within the range established by the variablE authority command.
Claim 8
Dependent Claim
68 words
A steering system for an aircraft as claimed in claim 1, in which the a.c. nose wheel angular follow-up signal (Nc) is connected into said circuit means in opposite phase relation to that of the pilot command signal (Rc) thereat and provide a final control signal (Cs) to said servomotor means whereby its deflection of the nose wheel is within the range established by the variable authority command.
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) | 1978-05-26 | 1978-11-25 | 1979-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-26 | 1982-11-25 | 1983-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-26 | 1986-11-25 | 1987-05-27 | $7700.00 | Window Closed / Lapsed |