Patent US4294787A successfully refreshed from Google Patents.
US4294787A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing reinforced composite racket frame
Assignee: Individual
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Filing: 1980-05-05
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Granted: 1981-10-13
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Expires: 2000-05-05
Abstract
Abstract This invention discloses an improved method of producing fiber glass or fiber graphite reinforced racket frames in which a shell made of a plurality of layers of resin-impregnated oriented graphite fibers is squeezed during the heating period to contact completely with the inner surface of a mold cavity by means of two interior pressure separately generated by compressed air and a foamable elastomer or rubber composition wrapped within the shell.
Inventors
- 👤 Kun-Nan Lo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 05:00
CPC Classifications
B; B29; B29C; B29C70/00; B29C70/04; B29C70/28; B29C70/40; B29C70/42; B29C70/44; B29C70/446; A; A63; A63B; A63B49/00; A63B49/02; A63B49/10; A63B49/11; B29C44/00; B29C44/02; B29C44/10; B29C44/12; B29C44/14; B29C44/16; A63B2209/00; A63B2209/02; A63B2209/023; B29C43/00; B29C43/02; B29C43/10; B29C43/12; B29K; B29K2105/00; B29K2105/06; B29K2105/08; B29K2105/0854; B29K2307/00; B29L; B29L2031/00; B29L2031/52; B29L2031/5245
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
130 words
A method of producing reinforced composite racket frames composed of an outer shell made of a thermosetting material and a foam core comprising the steps of: (a) inserting a foamable material in a shell of thermosetting material, the outer dimension of the foamable material being less than the inner dimension of the shell so as to create a space between said shell and said foamable material; (b) inserting the shell and the foamable into a mold; (c) initially pressurizing the space with pressurized gas to force the shell to intimately contact the inner surface of the mold; and (d) after the initial pressurizing step, heating the mold to a temperature at which the foamable material expands to subsequently fill said space and to pressurize said space by said foamable material.
Claim 2
Independent Claim
130 words
A method of producing reinforced composite racket frames composed of an outer shell made of a thermosetting material and a foam core comprising the steps of: (a) inserting a foamable material in a shell of thermosetting material, the outer dimension of the foamable material being less than the inner dimension of the shell so as to create a space between said shell and said foamable material; (b) inserting the shell and the foamable into a mold; (c) initially pressurizing the space with pressurized gas to force the shell to intimately contact the inner surface of the mold; and (d) after the initial pressurizing step, heating the mold to a temperature at which the foamable material expands to subsequently fill said space and to pressurize said space by said foamable material.
Claim 3
Dependent Claim
17 words
The method according to claim 1, wherein said foamable material is a foamable elastomer or rubber composition.
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) | 1984-10-12 | 1985-04-13 | 1985-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-12 | 1989-04-13 | 1989-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-12 | 1993-04-13 | 1993-10-13 | $7700.00 | Window Closed / Lapsed |