Patent US3772115A successfully refreshed from Google Patents.
US3772115A
Expired / Lapsed
US
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Process for producing reinforced carbon and graphite bodies
Assignee: Unifrax I LLC
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Filing: 1970-05-14
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Granted: 1973-11-13
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Expires: 1990-05-14
Abstract
Abstract A high strength carbon or graphite body formed from a carbon or graphite fiber composite shape having fibers running in three dimensions and a carbon or graphite matrix. The fiber composite is formed by needling layers of carbon or graphite fibers to position some of the fibers of each layer into a running direction substantially perpendicular to the running direction of the layers.
Inventors
- 👤 W Carlson
- 👤 L Ehrenreich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:04
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/71; C04B35/78; C04B35/80; C04B35/83; D; D04; D04H; D04H1/00; D04H1/70; D04H1/72; D04H5/00; D04H5/02
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
14 words
The process of claim 1 wherein the independent carbon fibers are chopped carbon fibers.
Claim 2
Dependent Claim
16 words
providing, over the surface of the fiber shape, a layer of randomly oriented, independent carbon fibers;
Claim 3
Dependent Claim
40 words
The process of claim 1 wherein said shape is needled a first time and additional layers of fibers are added and needled thereto, and repeating said adding and needling steps to build said shape to a desired number of layers.
Claim 4
Dependent Claim
60 words
subjecting the layers of fibrous material to penetration by barbed needles, said needles passing first through the layer of randomly oriented, independent carbon fibers, whereby a. the needle barbs become loaded with independent carbon fibers and carry the independent carbon fibers into the fiber shape, and b. independent carbon fibers are deposited within the fiber shape to provide interlaminar reinforcement;
Claim 5
Dependent Claim
9 words
impregnating the fiber shape with a carbonizable binder; and
Claim 6
Dependent Claim
20 words
The process of claim 1 wherein said fiber shape is formed by stacking sheets of cloth woven from said fibers.
Claim 7
Dependent Claim
19 words
The process of claim 1 wherein said shape is formed by winding layers of said fiber around a mandrel.
Claim 8
Dependent Claim
16 words
heating the impregnated shape at a sufficiently high temperature to cure and carbonize the binder therein.
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) | 1976-11-12 | 1977-05-14 | 1977-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-12 | 1981-05-14 | 1981-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-12 | 1985-05-14 | 1985-11-13 | $7700.00 | Window Closed / Lapsed |