Patent US4035265A successfully refreshed from Google Patents.
Patent US3858831A successfully refreshed from Google Patents.
US3858831A
Expired / Lapsed
US
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Nodal beam inertial flexure
Assignee: Bell Helicopter Textron Inc
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Filing: 1973-12-26
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Granted: 1975-01-07
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Expires: 1993-12-26
Abstract
Abstract A helicopter having a lift unit including a multiblade helicopter main rotor system and a nodalized module including a beam driven in response to blade developed vertical forces has a fuselage unit connected to the beam only at vibration nodal points along the beam. The coupling between the lift unit and the fuselage comprises two rigid arms which form the beam and which extend toward one another from the nodal points. A multilayered flexible beam section interconnects the arms to accommodate beam bending in the flexible section. A rigid member is attached to each of the arms at drive points intermediate the nodal points in supporting relation from the lift unit.
Inventors
- 👤 Dennis R Halwes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:01
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/001; B64C2027/002; B64C2027/005
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
108 words
In combination with a helicopter having a lift unit including a multiblade helicopter main rotor system, a nodalized module including a beam means driven in response to blade developed vertical forces and a fuselage unit connected to said beam means only at vibration nodal points along said beam, the improvement which comprises: a. two rigid arms forming said beam extending toward one another from said nodal points, b. a multilayered flexible beam section interconnecting said arms to accommodate beam bending in said section, and c. a rigid member attached to each of said arms at drive points intermediate said nodal points in supporting relation from said lift unit.
Claim 2
Dependent Claim
108 words
In combination with a helicopter having a lift unit including a multiblade helicopter main rotor system, a nodalized module including a beam means driven in response to blade developed vertical forces and a fuselage unit connected to said beam means only at vibration nodal points along said beam, the improvement which comprises: a. two rigid arms forming said beam extending toward one another from said nodal points, b. a multilayered flexible beam section interconnecting said arms to accommodate beam bending in said section, and c. a rigid member attached to each of said arms at drive points intermediate said nodal points in supporting relation from said lift unit.
Claim 3
Dependent Claim
58 words
The combination in claim 1 wherein a pair of said beams are provided each with a pair of said rigid members, said beams extending longitudinally relative to said fuselage unit and on opposite sides of the axis of said rotor system with extensions of the axis of said members intersecting above the center of rotation of the pylon.
Claim 4
Dependent Claim
35 words
The combination in claim 1 wherein said beam is chaRacterized by an elastomeric multilamina middle section imbedding a plurality of parallel longitudinally extending spring plates for control of the spring constant of said beam means.
Claim 5
Dependent Claim
108 words
In combination with a helicopter to be nodalized to minimize transfer of vibration from the rotor pylon structure to the fuselage which comprises: a. two flexible beams extending longitudinally of said fuselage, each of said beams characterized by an elastomeric multilamina middle section inbedding a plurality of parallel longitudinally extending plates for control of the spring constant of said beams, one on each side of said pylon, b. rigid link means to attach each beam to said pylon from drive points intermediate the ends of said beams, and c. means to couple each said beam to said fuselage at nodal points on said beams outside said drive points.
Claim 6
Dependent Claim
108 words
In combination with a helicopter to be nodalized to minimize transfer of vibration from the rotor pylon structure to the fuselage which comprises: a. two flexible beams extending longitudinally of said fuselage, each of said beams characterized by an elastomeric multilamina middle section inbedding a plurality of parallel longitudinally extending plates for control of the spring constant of said beams, one on each side of said pylon, b. rigid link means to attach each beam to said pylon from drive points intermediate the ends of said beams, and c. means to couple each said beam to said fuselage at nodal points on said beams outside said drive points.
Claim 7
Dependent Claim
34 words
The combination set forth in claim 4 in which the two rigid members attached to each of said beams have the extension of their axes intersecting above the center of rotation of the pylon.
Claim 8
Dependent Claim
76 words
A helicopter system which minimizes vertical pylon vibrations while operating in a focused rotor mode, which comprises: a. nodalized compound beam means having a flexible multilayered center beam fixedly attached to a fuselage at beam nodal points for isolation of vertical vibrations; b. support means extending from said beam means to a main rotor mounting for coupling said mounting to said fuselage; and c. torque linking means connected between said main rotor mounting and said fuselage.
Claim 9
Dependent Claim
76 words
A helicopter system which minimizes vertical pylon vibrations while operating in a focused rotor mode, which comprises: a. nodalized compound beam means having a flexible multilayered center beam fixedly attached to a fuselage at beam nodal points for isolation of vertical vibrations; b. support means extending from said beam means to a main rotor mounting for coupling said mounting to said fuselage; and c. torque linking means connected between said main rotor mounting and said fuselage.
Claim 10
Dependent Claim
66 words
The combination set forth in claim 6 wherein said nodalized compoumd beam means includes two compound beams laterally displaced on opposite sides of the axis of said rotor mounting and aligned longitudinally with said fuselage, and wherein each of said two compound beams comprises two rigid arms extending toward each other from beam nodal points and said flexible multilayered center beam interconnecting said two rigid arms.
Claim 11
Dependent Claim
47 words
The combination set forth in claim 7 wherein said support means includes four rigid support members, with each of said four members connected to said rotor mounting and to one end of one of said two compound beams at a driving point intermediate to beam nodal points.
Claim 12
Dependent Claim
94 words
The combination set forth in claim 8, wherein lower ends of a first pair of said support members connected to aft-most ends of said two compound beams are canted toward each other, and center lines extending through said first pair intersect on a longitudinal line passing through a center of gravity of said helicopter system, and wherein lower ends of a second pair of said support members connected to forward ends of said two compound beams are canted toward each other, and center lines extending through said second pair intersect on said longitudinal line.
Claim 13
Dependent Claim
44 words
The combination set forth in claim 9 wherein said support members connected to same one of said two compound beams have upper ends canted toward each other with center lines extending therefrom intersecting on a lateral line passing through said pylon center of percussion.
Claim 14
Dependent Claim
49 words
The combination set forth in claim 7 wherein said torque linking means includes a pair of rigid members extending aft and perpendicular to said pylon, and wherein each of said pair is subtended by linked toggle members which in turn are linked to elastomeric mounts attached to said fuselage.
Claim 15
Dependent Claim
46 words
The combination set forth in claim 7 wherein each of said two compound beams includes a load fixedly attached to one of said two rigid arms to change the natural frequency of said two compound beams and permit a reduction of distance between beam nodal points.
Claim 16
Dependent Claim
41 words
The combination set forth in claim 6 wherein said nodalized compound beam means includes a single longitudinally aligned compound beam comprising two arms extending toward one another from beam nodal points, and said flexible multilayered center beam interconnecting said two arms.
Claim 17
Dependent Claim
138 words
The combination set forth in claim 13 wHerein said support means includes two pairs of rigid support members each connected between said main rotor mounting and one end of said compound beam at driving points intermediate to beam nodal points, wherein said torque linking means includes a single torque link connected between said rotor mounting and a pair of elastomeric mounts secured to a forward one of said two arms at driving points intermediate to beam nodal points, and wherein a pair of laterally extending and rigid fuselage links are each secured to one of said two arms at driving points outside of an area intermediate to beam nodal points, and a longitudinally extending fuselage link is secured to aft one of said two arms at a driving point outside of an area intermediate to beam nodal points.
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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) | 1978-01-06 | 1978-07-08 | 1979-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-06 | 1982-07-08 | 1983-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-06 | 1986-07-08 | 1987-01-07 | $7700.00 | Window Closed / Lapsed |