Patent US3579422A successfully refreshed from Google Patents.
US3579422A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filament wound cylindrical structures for use in paper making
Assignee: Sinclair Co
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Filing: 1968-10-07
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Granted: 1971-05-18
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Expires: 1988-10-07
Abstract
Abstract CYLINDRICAL STRUCTURE, SUCH AS A "DANDY ROLL", CONSTRUCTED BY THE METHOD OF CONTINUOUS FILAMENT WINDING IN A HONEYCOMB OR OPEN-WORK PATTERN FORMED ON A COLLAPSIBLE MANDREL. THE FILAMENTS ARE IMPREGNATED WITH A THERMOSETTING RESIN AT THE TIME OF THEIR APPLICATION TO THE MANDREL AND THE RESIN IS CURED AND HARDENED TO PROVIDE THE OPEN-WORK RIB STRUCTURE. IN ONE EMBODIMENT THE STRUCTURE IS COMPOSED OF UPSTANDING RIBS FORMED ON THE DANDY ROLL AND BONDED TOGETHER IN A HEXAGONAL-TRIANGULAR HONEYCOMB PATTERN.
Inventors
- 👤 David G Minick
- 👤 David H Sinclair
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:08
CPC Classifications
D; D21; D21F; D21F1/00; D21F1/44; D21F1/46
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-17 | 1974-11-16 | 1975-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-17 | 1978-11-16 | 1979-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-17 | 1982-11-16 | 1983-05-18 | $7700.00 | Window Closed / Lapsed |