Patent DE740987C successfully refreshed from Google Patents.
US5222297A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite blade manufacture
Assignee: RTX Corp
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Filing: 1991-10-18
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Granted: 1993-06-29
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Expires: 2011-10-18
Abstract
Abstract A method of manufacturing a lightweight composite propulsor blade of spar and shell construction comprises forming a composite spar (30) having an elongated foam body (20) bonded to a short metal retention tulip (10) and overlayed with a dry braided wrap of angular structural fibers and substantially unidirectional spanwisely aligned structural fiber plies disposed between the braided layers; adding a leading edge foam body (42) and a trailing edge foam body (44) to the spar assembly to form a blade subassembly (50); providing a dry braided fabric wrap over the blade assembly; disposing the fabric covered blade subassembly into a shell molding die and simultaneously impregnating the dry spar fabric wrap and the dry shell fabric wrap with a curable resin material; and curing the impregnated blade subassembly.
Inventors
- 👤 John M. Graff
- 👤 John A. Violette
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:17
CPC Classifications
B; B29; B29D; B29D99/00; B29D99/0025; B29C; B29C70/00; B29C70/68; B29C70/86; B29C70/865; B64; B64C; B64C11/00; B64C11/16; B64C11/20; B64C11/26; Y; Y02; Y02T; Y02T50/00; Y02T50/60; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49316; Y10T29/49336; Y10T29/49337
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
220 words
A method of manufacturing a lightweight composite propulsor blade having an axially extending load bearing spar disposed within a fiber reinforced shell comprising the steps of: a. forming a spar subassembly having a short metal retention member and a core of lightweight cellular material extending axially outwardly from the retention member; b. repeatedly braiding fibers of a structural fiber over the length of the spar subassembly to provide a dry wrap about the spar subassembly formed of a plurality of layers of angularly woven structural fibers; c. during said spar braiding step, laying up spanwisely extending plies of substantially unidirectional structural fibers between successive angularly woven layers; d. forming a first filler body of lightweight cellular material on a leading edge of the braided spar assembly and a second filler body of lightweight cellular material on a trailing edge of the braided spar assembly to form a blade subassembly; e. forming a dry shell warp of braided angularly woven fabric about the blade subassembly; and f. simultaneously impregnating the dry braided fiber wrap of the braided spar assembly and the dry braided fabric shell wrap about the blade subassembly with a curable resin material whereby upon subsequent curing of the resin material a blade assembly having a composite fiber reinforced load bearing spar and composite fiber reinforced shell is formed.
Claim 2
Independent Claim
220 words
A method of manufacturing a lightweight composite propulsor blade having an axially extending load bearing spar disposed within a fiber reinforced shell comprising the steps of: a. forming a spar subassembly having a short metal retention member and a core of lightweight cellular material extending axially outwardly from the retention member; b. repeatedly braiding fibers of a structural fiber over the length of the spar subassembly to provide a dry wrap about the spar subassembly formed of a plurality of layers of angularly woven structural fibers; c. during said spar braiding step, laying up spanwisely extending plies of substantially unidirectional structural fibers between successive angularly woven layers; d. forming a first filler body of lightweight cellular material on a leading edge of the braided spar assembly and a second filler body of lightweight cellular material on a trailing edge of the braided spar assembly to form a blade subassembly; e. forming a dry shell warp of braided angularly woven fabric about the blade subassembly; and f. simultaneously impregnating the dry braided fiber wrap of the braided spar assembly and the dry braided fabric shell wrap about the blade subassembly with a curable resin material whereby upon subsequent curing of the resin material a blade assembly having a composite fiber reinforced load bearing spar and composite fiber reinforced shell is formed.
Claim 3
Dependent Claim
39 words
A method as recited in claim 1 wherein the step of forming a dry shell wrap of braided angularly woven fabric about the blade subassembly comprises fitting at least one dry preformed braided fabric sock over the blade subassembly.
Claim 4
Dependent Claim
91 words
A method as recited in claim 2 wherein the step of forming a first filler body of lightweight cellular material on a leading edge of the braided spar assembly and a second filler body of lightweight cellular material on a trailing edge of the spar assembly to form a blade subassembly comprises: a. disposing the braided spar assembly into a molding die; and b. injecting a lightweight cellular material into the molding die to form the leading edge foam filler and the trailing edge foam filler on the braided spar subassembly.
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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) | 1996-06-28 | 1996-12-28 | 1997-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-28 | 2000-12-28 | 2001-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-06-28 | 2004-12-28 | 2005-06-29 | $7700.00 | Window Closed / Lapsed |