US3791234A
Expired / Lapsed
US
⏱️ 0.0 years remaining
A retention member
Assignee: Lockheed Martin Corp
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Filing: 1972-05-08
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Granted: 1974-02-12
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Expires: 1992-05-08
Abstract
Abstract A blade retention member which is compressible and torsionable in installation and operation of a rotor control system, the torsional stiffness of the member decreasing with increasing rotor blade speed, the compressible stress not exceeding the strength of the material out of which the member is fabricated. Its inboard end is fixedly connected to either the rotor blade or a movable hub enveloping it at its inboard end, while its outboard end is fixedly connected to the fixed hub or extension thereof in the rotor system. Means are also provided in the system for isolating bearing means supporting the blade from the blade retention member. The member itself comprises a plurality of circumferentially spaced parallel rails spacedly disposed radially equidistant and arcuately about from a common centerline coincident with the feathering axis for the blade.
Inventors
- 👤 H Kastan
- 👤 J Pena
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:33
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/32; B64C27/327; B64C27/33; Y; Y10; Y10T; Y10T74/00; Y10T74/21; Y10T74/2142
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
70 words
A compression-torsion pack comprising a pair of elongate components assembled together, a plurality of circumferentially spaced parallel rails in each of said elongate components, whereby upon such assembly of said components, said rails are disposed radially equidistant from a common center line for said pack, and mounting end portions integrally formed on opposite ends of and to said plurality of spaced rails for installment, such as in a rotor system.
Claim 2
Dependent Claim
70 words
A compression-torsion pack comprising a pair of elongate components assembled together, a plurality of circumferentially spaced parallel rails in each of said elongate components, whereby upon such assembly of said components, said rails are disposed radially equidistant from a common center line for said pack, and mounting end portions integrally formed on opposite ends of and to said plurality of spaced rails for installment, such as in a rotor system.
Claim 3
Dependent Claim
14 words
The pack of claim 1 wherein each of said rails is H-configured in cross-section.
Claim 4
Dependent Claim
141 words
The pack of claim 1 including means rigidly connecting said components together at both ends of the pack for assembly thereof, means for securing said pack at the one end thereof to a structural member disposed at the other end of the pack and extending to said securing means, such as to a rotor blade in the rotor system, means at the other end of said pack for installing the assembly to a structural member disposed at the one end of said pack and extending to said installing means, such as to a rotor hub in the rotor system, and means for clamping the one end of said pack to the structural member disposed at the other end and extending to said clamping means to prevent the one end of said pack from rotating in an in-plane axis for said pack.
Claim 5
Dependent Claim
21 words
The pack of claim 3 including means defining a cavity at such one end, said clamping means disposed in the cavity.
Claim 6
Dependent Claim
23 words
The pack of claim 4 including a ball bearing means mounted on said shaft, said portion of said clamping means rotatably mounted thereon.
Claim 7
Dependent Claim
40 words
The pack of claim 4 wherein said clamping means includes a shaft mounted across said cavity along the common center line for said pack and a portion of said clamping means about said shaft clamping upon the corresponding structural member.
Claim 8
Dependent Claim
131 words
An elongate, torsionally flexible and axially stiff blade retention member for isolating flapping and chordwise forces in a rotary wing vehicle having a hub assembly and rotor blade and comprising in combination, a plurality of circumferentially spaced parallel elongate rails, said rails being disposed arcuately about and equidistant from a common center line for said member, an inboard mounting end portion and an outboard mounting end portion each formed on a respective end of and to said plurality of rails, means for installing said outboard mounting end portion to the hub assembly for the rotary wing vehicle, means for securing said inboard mounting end portion to the rotor blade, and means mounted at said inboard mounting end portion for fully constraining in vertical and horizontal movement said inboard mounting end portion.
Claim 9
Dependent Claim
131 words
An elongate, torsionally flexible and axially stiff blade retention member for isolating flapping and chordwise forces in a rotary wing vehicle having a hub assembly and rotor blade and comprising in combination, a plurality of circumferentially spaced parallel elongate rails, said rails being disposed arcuately about and equidistant from a common center line for said member, an inboard mounting end portion and an outboard mounting end portion each formed on a respective end of and to said plurality of rails, means for installing said outboard mounting end portion to the hub assembly for the rotary wing vehicle, means for securing said inboard mounting end portion to the rotor blade, and means mounted at said inboard mounting end portion for fully constraining in vertical and horizontal movement said inboard mounting end portion.
Claim 10
Dependent Claim
34 words
The blade retention member of claim 7 wherein said securing means includes a pair of pins in opposing relationship and adapted to be connected to said inboard mounting end portion to the rotor blade.
Claim 11
Dependent Claim
21 words
The blade retention member of claim 8 wherein said securing means further includes bolt-nut means mounted through said pair of pins.
Claim 12
Dependent Claim
54 words
The blade retention member of claim 7 wherein said fully constraining means comprises means defining a cavity in said inboard mounting end portion, a shaft mounted in said cavity along the common center line for said member, and clamping means rotatably mounted about said shafT and having a portion clampable to the rotor hub.
Claim 13
Dependent Claim
28 words
The blade retention member of claim 10 including spherical bearing means mounted on said shaft in said cavity, said portion of said clamping means being rotatably mounted thereon.
Claim 14
Dependent Claim
34 words
The blade retention member of claim 11 wherein said securing means includes a pair of pins in opposing relationship and adopted to be connected to said inboard mounting end portion to the rotor blade.
Claim 15
Dependent Claim
21 words
The blade retention member of claim 12 wherein said securing means further includes bolt-nut means mounted through said pair of pins.
Claim 16
Dependent Claim
14 words
The blade retention member of claim 13 wherein said bolt-nut means captures said shaft.
References Cited (Backward Citations)
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Cited
US1853712A
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US3334886A
Cited
US2995953A
Cited
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US3667863A
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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) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |