US3744477A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fireplace unity with thin rear firebox wall
Assignee: Heatilator Inc
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Filing: 1971-10-12
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Granted: 1973-07-10
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Expires: 1991-10-12
Abstract
Abstract A fireplace unit adapted for permanent, fully enclosed installation wherein the rear wall of the firebox or combustion chamber is of thin, sheet metal. Passageways are provided outside the combustion chamber for the flow of cooling air to substantially eliminate the possibility of damage to the rear wall due to the intense heat concentrated thereon.
Inventors
- 👤 G Andrews
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 02:26
CPC Classifications
F; F24; F24B; F24B1/00; F24B1/18
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
161 words
A fireplace unit for permanent installation and enclosure as part of a structure, said unit comprising: a. an open front combustion chamber having a hearth floor, side and rear walls and a flue for exhauSt of combustion products; b. said hearth floor being raised from the supporting structure to provide a passage for air thereunder; c. a second wall substantially parallel to and spaced rearwardly from said rear wall to define therebetween a space enclosed at the top, bottom and sides; d. a third wall substantially parallel to and spaced rearwardly from said second wall to define therebetween a space open at the bottom to communicate with said passage, whereby air may pass directly from said passage into the space between said second and third walls; and e. means defining a plurality of openings in said second wall to allow air to pass between the space between said second and third walls, and the space between said second and rear walls.
Claim 2
Dependent Claim
161 words
A fireplace unit for permanent installation and enclosure as part of a structure, said unit comprising: a. an open front combustion chamber having a hearth floor, side and rear walls and a flue for exhauSt of combustion products; b. said hearth floor being raised from the supporting structure to provide a passage for air thereunder; c. a second wall substantially parallel to and spaced rearwardly from said rear wall to define therebetween a space enclosed at the top, bottom and sides; d. a third wall substantially parallel to and spaced rearwardly from said second wall to define therebetween a space open at the bottom to communicate with said passage, whereby air may pass directly from said passage into the space between said second and third walls; and e. means defining a plurality of openings in said second wall to allow air to pass between the space between said second and third walls, and the space between said second and rear walls.
Claim 3
Dependent Claim
23 words
The invention according to claim 1 wherein said rear wall is constructed entirely of sheet metal on the order of 0.020 inches thick.
Claim 4
Dependent Claim
13 words
The invention according to claim 2 wherein said sheet metal is stainless steel.
Claim 5
Dependent Claim
109 words
The invention according to claim 1 wherein said openings in said second wall are provided both near the bottom and near the top thereof, whereby a first portion of the air passing from the space under said hearth to that between said second and third walls remains therebetween as it is heated and rises, and a second portion of said air passes through the openings near the botton of said second wall into the space between said rear and second walls and is heated and rises therebetween and passes back to the space between said second and third walls through the openings near the top of said second wall.
Claim 6
Dependent Claim
67 words
The invention according to claim 4 and further including an inner hood disposed above said combustion chamber to enclose the combustion products rising therefrom, an outer hood enclosing said inner hood in spaced relation thereto, and means for directing the air which has passed beneath said hearth into the space between said inner and outer hoods and through openings in said inner hood into the interior thereof.
Claim 7
Dependent Claim
85 words
The invention according to claim 5 wherein said second wall is disposed below and contiguously with a portion of said inner hood, and said third wall extends into the space between said inner and outer hoods and is joined at the top and sides of said inner hood, whereby said first and second portions of air are directed into the space between said inner hood and the extension of said third wall and enter said inner hood through openings therein communicating with said last-named space.
Claim 8
Dependent Claim
63 words
The invention according to claim 6 and further including a fourth wall disposed in a plane substantially parallel to and rearwardly spaced from said third wall, and below and contiguously with said outer hood, and a portion of the air passing under said hearth is directed into the space between said third and fourth walls and thence between said inner and outer hoods.
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) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |