US3889902A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Helicopter comprising a plurality of lifting rotors and at least one propelling unit
Assignee: Individual
•
Filing: 1973-12-26
•
Granted: 1975-06-17
•
Expires: 1993-12-26
Abstract
Abstract A multi-rotor helicopter comprising a polygonal platform having mounted symmetrically along its outer periphery a number 2n of short-bladed lifting rotors. These rotors are adapted either to be driven by pairs in opposite directions by a same number 2n of gas turbines, specially for vertical landing and take-off, or to rotate freely (windmilling) when the aircraft is propelled horizontally by a jet engine, also mounted on the platform. This platform also supports a cockpit or crew cabin.
Inventors
- 👤 Francois Madet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 08:16
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/04; B64C27/08
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
146 words
A multi-rotor helicopter comprising a platform of polygonal configuration having 2n sides and at least one median axis, a propelling jet-engine for horizontal flight, disposed along said platform median axis, a number n of pairs of short-bladed lift rotors having a diameter smaller than that of said platform, the two rotors of each pair rotating in opposite directions and being disposed symmetrically in relation to the axis of said platform along the periphery thereof, with a relative angular shift of 180*/n, the axes of each pair of rotors converging to a point located above the median axis of said platform and the centre thereof, n pairs of gas turbines mounted adjacent the periphery of said platform, and having corresponding rotors coupled coaxially to said 2n lift rotors, means for producing propelling gases and means for distributing in a controlled manner said propelling gases to said turbines.
Claim 2
Dependent Claim
146 words
A multi-rotor helicopter comprising a platform of polygonal configuration having 2n sides and at least one median axis, a propelling jet-engine for horizontal flight, disposed along said platform median axis, a number n of pairs of short-bladed lift rotors having a diameter smaller than that of said platform, the two rotors of each pair rotating in opposite directions and being disposed symmetrically in relation to the axis of said platform along the periphery thereof, with a relative angular shift of 180*/n, the axes of each pair of rotors converging to a point located above the median axis of said platform and the centre thereof, n pairs of gas turbines mounted adjacent the periphery of said platform, and having corresponding rotors coupled coaxially to said 2n lift rotors, means for producing propelling gases and means for distributing in a controlled manner said propelling gases to said turbines.
Claim 3
Dependent Claim
64 words
Helicopter as set forth in claim 1, further comprising a pair of turning-thrust nozzles adapted to produce substantially horizontal thrusts in corresponding directions across said platform median axis, said nozzles being arranged symmetrically to one another in relation to said axis, and means for distributing in a controlled manner one fraction of the propelling gases produced by said propelling jet-engine to said turning-thrust nozzles.
Claim 4
Dependent Claim
33 words
Helicopter as set forth in claim 1, wherein said propelling jet-engine comprises an ejection nozzle adapted to pivot in at least one of two planes, namely a vertical plane and a horizontal plane.
Claim 5
Dependent Claim
53 words
Helicopter as set forth in claim 1, wherein each rotor of each lift rotor has a shaft pivotally mounted to the rotor of the corresponding turbine, externally thereof, said shaft extending parallel to one radius of said turbiNe rotor, means being also provided for pivoting simultaneously all the blades of said lift rotor.
Claim 6
Dependent Claim
134 words
Helicopter as set forth in claim 1, wherein the rotor of each turbine comprises a hollow shaft, means for pivoting simultaneously all the blades of the corresponding lift rotor comprising a rod having an intermediate portion slidably engaging said hollow shaft of said turbine rotor, a first end of said rod extending in close vicinity of the ends of the shafts of the various blades of said lift rotor, a bearing in which said first end of said rod is rotatably engaged, means acting upon the other end of said rod for controlling the sliding movements thereof in said hollow shaft of said turbine rotor, and coupling means for converting the motion imparted to said bearing by said sliding rod into pivoting movements of the shafts of all the blades of said lift rotor.
Claim 7
Dependent Claim
67 words
Helicopter as set forth in claim 1, comprising in additon a gas distributing box disposed along the median axis of said platform, in alignment with a jet-engine and said propelling nozzle, an outlet of said box connected to said propelling nozzle, and feed conduits extending in directions moderately inclined to the propelling nozzle and inserted between the other outlets of said distributing box and the corresponding turbines.
Claim 8
Dependent Claim
44 words
Helicopter as set forth in claim 1, wherein said lift rotors and the corresponding turbines are carried by radial arms respectively which extend from said platform to a distance from the upper periphery thereof which is greater than the radius of said lift rotors.
Claim 9
Dependent Claim
105 words
Helicopter as set forth in claim 1, further comprising three legs of relatively substantial height having their upper ends secured to the lower face of said platform, the first leg being located beneath the median axis of said platform and the other two legs being disposed on either of said median axis, with their lower ends spread apart by a distance substantially greater than the transverse dimension of said platform, and a three-wheel landing gear comprising a first steerable wheel mounted at the lower end of said first leg, the two other non-swivelling wheels being mounted at the lower ends of the two other legs.
Claim 10
Dependent Claim
40 words
Helicopter as set forth in claim 1, further comprising an auxiliary generator and switching means whereby said auxiliary generator can operate as a substitute for the main generator in case of emergency such as a failure of said main generator.
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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) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |