US4811538A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fire-resistant door
Assignee: Georgia Pacific Gypsum LLC
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Filing: 1987-10-20
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Granted: 1989-03-14
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Expires: 2007-10-20
Abstract
Abstract A fire-resistant door comprises a core panel of mineral material, such as gypsum wallboard. A fiber mat, preferably comprising glass fibers, is at least partially embedded in each face of said core panel. An edge banding assembly disposed around the periphery of the core panel is centrally grooved to receive the panel edges. Facing sheets are affixed to the opposite sides of the edge banding assembly in spaced parallel relation to the core panel, and a spacer material at least partially fills the spaces between the facing sheets and the core panel.
Inventors
- 👤 Charles W. Lehnert
- 👤 George F. Fowler, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:08
CPC Classifications
E; E06; E06B; E06B5/00; E06B5/10; E06B5/16; E06B3/00; E06B3/70; E06B3/7015; E06B2003/7032; E06B2003/7036; Y; Y10; Y10T; Y10T428/00; Y10T428/23; Y10T428/232
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
81 words
A fire-resistant door comprising: a core panel of mineral material, said core panel including a fiber mat coextensive with and at least partially embedded in each face of said panel, an edge banding assembly disposed around the periphery of said core panel, a door facing sheet affixed to each side of said edge banding assembly in spaced parallel relation to said core panel, and a spacer material at least partially filling the spaces between said facing sheets and said core panel.
Claim 2
Dependent Claim
81 words
A fire-resistant door comprising: a core panel of mineral material, said core panel including a fiber mat coextensive with and at least partially embedded in each face of said panel, an edge banding assembly disposed around the periphery of said core panel, a door facing sheet affixed to each side of said edge banding assembly in spaced parallel relation to said core panel, and a spacer material at least partially filling the spaces between said facing sheets and said core panel.
Claim 3
Dependent Claim
17 words
The invention as claimed in claim 1, wherein said core panel is less than about 0.5" thick.
Claim 4
Dependent Claim
16 words
The invention as claimed in claim 1, wherein said fiber mat comprises a glass fiber mat.
Claim 5
Dependent Claim
30 words
The invention as claimed in claim 1, wherein said edge banding assembly is centrally grooved around its internal edges to receive the edges of said core panel within said groove.
Claim 6
Dependent Claim
19 words
The invention as claimed in claim 1, wherein said edge banding assembly comprises a rectangular frame of wooden elements.
Claim 7
Dependent Claim
19 words
The invention as claimed in claim 1, wherein said facing sheets are adhesively affixed to said edge banding assembly.
Claim 8
Dependent Claim
15 words
The invention as claimed in claim 1, wherein said facing sheets are formed of hardboard.
Claim 9
Dependent Claim
21 words
The invention as claimed in claim 1, wherein said facing sheets are decoratively configured to simulate a quarter panel door face.
Claim 10
Dependent Claim
14 words
The invention as claimed in claim 1, wherein said facing sheets are planar sheets.
Claim 11
Dependent Claim
16 words
The invention as claimed in claim 1, wherein said spacer material comprises a rigid plastic foam.
Claim 12
Dependent Claim
16 words
The invention as claimed in claim 1, wherein said spacer material comprises a honeycomb cardboard material.
Claim 13
Dependent Claim
18 words
The invention as claimed in claim 1, wherein said core panel comprises a single panel of gypsum wallboard.
Claim 14
Dependent Claim
21 words
The invention as claimed in claim 12, wherein said core panel has a density of about 40 to about 50 lbs/cu.ft.
Claim 15
Dependent Claim
114 words
A fire-resistant door comprising: a core panel of gypsum wallboard material, said core panel including a glass fiber mat coextensive with and at least partially embedded in each face of said panel, an edge banding assembly comprising a rectangular frame of wooden elements disposed around the periphery of said core panel, said edge banding assembly elements being centrally grooved around their internal edges to receive the edges of said core panel within said groove, a door facing sheet adhesively affixed to each side of said edge banding assembly in spaced parallel relation to said core panel, and a spacer material at least partially filling the spaces between said facing sheets and said core panel.
Claim 16
Dependent Claim
114 words
A fire-resistant door comprising: a core panel of gypsum wallboard material, said core panel including a glass fiber mat coextensive with and at least partially embedded in each face of said panel, an edge banding assembly comprising a rectangular frame of wooden elements disposed around the periphery of said core panel, said edge banding assembly elements being centrally grooved around their internal edges to receive the edges of said core panel within said groove, a door facing sheet adhesively affixed to each side of said edge banding assembly in spaced parallel relation to said core panel, and a spacer material at least partially filling the spaces between said facing sheets and said core panel.
Claim 17
Dependent Claim
21 words
The invention as claimed in claim 14, wherein said core panel has a density of about 40 to about 50 lbs/cu.ft.
Claim 18
Dependent Claim
20 words
The invention as claimed in claim 14, wherein said core panel has a density of about 42 to about 45/lbs/cu.ft.
Claim 19
Dependent Claim
17 words
The invention as claimed in claim 14, wherein said core panel is less than about 0.5" thick.
Claim 20
Dependent Claim
15 words
The invention as claimed in claim 14, wherein said facing sheets are formed of hardboard.
Claim 21
Dependent Claim
21 words
The invention as claimed in claim 14, wherein said facing sheets are decoratively configured to simulate a quarter panel door face.
Claim 22
Dependent Claim
14 words
The invention as claimed in claim 14, wherein said facing sheets are planar sheets.
Claim 23
Dependent Claim
16 words
The invention as claimed in claim 14, wherein said spacer material comprises a rigid plastic foam.
Claim 24
Dependent Claim
16 words
The invention as claimed in claim 14, wherein said spacer material comprises a honeycomb cardboard material.
Claim 25
Dependent Claim
22 words
The invention as claimed in claim 14, wherein said spacer material is adhesively bonded to said facing sheets and said core panel.
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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) | 1992-03-13 | 1992-09-12 | 1993-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-13 | 1996-09-12 | 1997-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-13 | 2000-09-12 | 2001-03-14 | $7700.00 | Window Closed / Lapsed |