US4422627A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Endless spring, such as ringspring
Assignee: Airbus Helicopters Deutschland GmbH
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Filing: 1981-06-01
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Granted: 1983-12-27
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Expires: 2001-06-01
Abstract
Abstract An endless spring is an elastic body such as an oval or elongated or circular ring body for the transmission of loads in a main plane substantially centrally through the endless or ring body. Such a main plane extends in the plane of the drawing. The ring body is made up of a plurality of winding layers of fiber reinforced synthetic material. The windings in certain central body layers (2) preferably extend unidirectionally and the fibers in intermediate layers (3) and in outer layers extend at an angle relative to a main load application direction. The whole spring body includes a plurality of intermediate layers (3) and a plurality of outer layers (4) of synthetic resin impregnated fabric plies. The central body layers (2) form a winding body.
Inventors
- 👤 Helmut Schmidt
- 👤 Ulrich Ramm
- 👤 Alexander Schroeder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:53
CPC Classifications
B; B29; B29C; B29C70/00; B29C70/04; B29C70/06; B29C70/08; B29C70/083; F; F16; F16F; F16F1/00; F16F1/36; F16F1/366; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24058; Y10T428/24074; Y10T428/24091; Y10T428/24099; Y10T428/24124; Y10T428/30
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
138 words
An endless spring comprising substantially straight leg portions connected by curved end portions, said endless spring forming a frame having a frame plane for taking up loads extending in said frame plane in a main load application direction, comprising a spring body having a plurality of layers (2, 3, 4) made of fiber compound materials and extending in parallel to said frame plane, said layers comprising a first layer type (2) in which fiber bundles are wound so that all the fibers extend unidirectionally in said first layer type and a second layer type (3, 4), each said second layer type comprising at least two plies (5, 6) in which the fibers extend in cross-over relationship relative to each other, said first layer type and said second layer type being arranged in alternate succession relative to each other.
Claim 2
Dependent Claim
138 words
An endless spring comprising substantially straight leg portions connected by curved end portions, said endless spring forming a frame having a frame plane for taking up loads extending in said frame plane in a main load application direction, comprising a spring body having a plurality of layers (2, 3, 4) made of fiber compound materials and extending in parallel to said frame plane, said layers comprising a first layer type (2) in which fiber bundles are wound so that all the fibers extend unidirectionally in said first layer type and a second layer type (3, 4), each said second layer type comprising at least two plies (5, 6) in which the fibers extend in cross-over relationship relative to each other, said first layer type and said second layer type being arranged in alternate succession relative to each other.
Claim 3
Dependent Claim
56 words
The endless spring of claim 1, wherein said second layer type comprises one layer more than said first layer type so that the second layer type forms outer surfaces parallel to said frame plane, and so that said first layer type forms inner layers interconnected by a second type layer between two neighboring first type layers.
Claim 4
Dependent Claim
62 words
The endless spring of claim 1, wherein said plies (5, 6) of said second layer type (3, 4) comprise at least one first ply (5) with fibers extending in parallel and at 90° relative to said main load application direction, and at least one second ply (6) with fibers extending in a ±45° cross-over relationship relative to said main load application direction.
Claim 5
Dependent Claim
92 words
The endless spring of claim 3, wherein each of said second layer type (3, 4) comprises said first and second plies (5, 6), wherein a second layer type (3) located internally of the spring between two first layer types (2) comprises at least two first plies (5) and a second ply (6) located between said two first plies (5), and wherein a second layer type (4) located externally of the spring comprises at least one first ply (5) and at least one second ply (6) located on the outside of the spring.
Claim 6
Dependent Claim
19 words
The spring of claim 1, wherein each of said first layer type (2) comprises at least two fiber bundles.
Claim 7
Dependent Claim
20 words
The spring of claim 1, wherein said plies of said second layer type are made of fibers of different materials.
Claim 8
Dependent Claim
22 words
The spring of claim 1, wherein said fiber bundles of said first layer type (2) are made of fibers of different materials.
Claim 9
Dependent Claim
32 words
The spring of claim 1, wherein said fiber bundles of said first layer type (2) and said plies of said second layer type (3, 4) are made of fibers of different materials.
Claim 10
Dependent Claim
19 words
The spring of claim 1, further comprising adhesive layers (7) operatively interposed between said first and second layer types.
Claim 11
Dependent Claim
53 words
The spring of claim 1, further comprising spring attachment means (8) operatively secured to said endless spring for applying a load to the spring, and wear resistant plate means (9) operatively interposed between said spring attachment means and said endless spring for reducing the wear imposed by the atrachment means on the spring.
Claim 12
Dependent Claim
15 words
The spring of claim 10, wherein said plate means (9) are made of spring steel.
Claim 13
Dependent Claim
39 words
The spring of claim 1, wherein said first and second layer types (2, 3, 4) form an endless loop having two straight legs extending in parallel to each other and two curved end portions operatively interconnecting said straight legs.
Claim 14
Dependent Claim
13 words
The spring of claim 1, wherein said spring body has a rectangular cross-section.
References Cited (Backward Citations)
DE655469C
Cited
US1126648A
Cited
US1173850A
Cited
US1709207A
Cited
US1709828A
Cited
US1739025A
Cited
US1789727A
Cited
US2245444A
Cited
US3107698A
Cited
DE1164757B
Cited
US3969568A
Cited
US4319620A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-26 | 1987-06-27 | 1987-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-26 | 1991-06-27 | 1991-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-26 | 1995-06-27 | 1995-12-27 | $7700.00 | Window Closed / Lapsed |