Patent US4299059A successfully refreshed from Google Patents.
US4299059A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermally insulated, fire resistant attic door
Assignee: HUNGTINGTON NATIONAL BANK
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Filing: 1980-03-10
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Granted: 1981-11-10
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Expires: 2000-03-10
Abstract
Abstract A ceiling-mounted attic door features a continuous outer panel of flame-resistant plaster board, an intermediate layer of thermal insulating material and marginal sealing gaskets and insulating strips arranged to thermally seal the marginal edges of the door when it occupies a normally closed position within its associated door opening.
Inventors
- 👤 William V. Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 22:58
CPC Classifications
E; E06; E06B; E06B5/00; E06B5/10; E06B5/16; E04; E04B; E04B1/00; E04B1/62; E04B1/92; E04B1/94; E04B1/941
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
96 words
A flame-resistant, thermally insulated trap door for hinged mounting in a ceiling opening and comprising: (a) a generally rectangular supporting frame; (b) at least one layer of incombustible, thermal insulating material carried within and closing said frame; (c) an outer facing panel of flame-resistant plaster board connected to one face of said frame in coextensive, covering relation to said frame and to said layer of thermal insulating material; and (d) a strip of flexible thermal insulating material positioned around the outer marginal edges of said frame for sealing engagement with the walls defining said ceiling opening.
Claim 2
Dependent Claim
96 words
A flame-resistant, thermally insulated trap door for hinged mounting in a ceiling opening and comprising: (a) a generally rectangular supporting frame; (b) at least one layer of incombustible, thermal insulating material carried within and closing said frame; (c) an outer facing panel of flame-resistant plaster board connected to one face of said frame in coextensive, covering relation to said frame and to said layer of thermal insulating material; and (d) a strip of flexible thermal insulating material positioned around the outer marginal edges of said frame for sealing engagement with the walls defining said ceiling opening.
Claim 3
Dependent Claim
64 words
A trap door according to claim 1 which further includes an inverted T-shaped, frame resistant trim strip carried at the marginal edges of said frame in overlying relation to the marginal edges of said outer facing panel and said strip of thermal insulating material and arranged to overlap the edges of the ceiling opening when said door occupies a closed position in said opening.
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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) | 1984-11-09 | 1985-05-11 | 1985-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-09 | 1989-05-11 | 1989-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-09 | 1993-05-11 | 1993-11-10 | $7700.00 | Window Closed / Lapsed |