US3695345A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controlled forced draft action to the flue of a gas fired heat exchanger
Assignee: Dunham Bush Inc
•
Filing: 1970-10-07
•
Granted: 1972-10-03
•
Expires: 1990-10-07
Abstract
Abstract The flue pipe leading from the combustion chamber of a gas fired heat exchanger has its discharge opening aligned with and conforming to the periphery the condenser fan for forcibly discharging the combustion products and maintaining proper draft. A damper valve within the flue pipe, intermediate of the gas fired heat exchanger and the condenser fan insures proper maintenance of the vacuum pressure within the combustion chamber regardless of wind conditions acting on the combined heating and cooling unit.
Inventors
- 👤 Colby D Moreland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:23
CPC Classifications
F; F23; F23L; F23L13/00; F24; F24F; F24F5/00
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
119 words
In a combination heating and cooling unit comprising a housing, a cooling unit within said housing including a condenser and an assembly including a condenser fan and shroud means encompassing said fan, and a fuel burning forced air furnace including a furnace heat exchanger assembly, the improvement comprising: a flue pipe leading from said furnace heat exchanger assembly for discharging products of combustion, said flue pipe having the discharge end extending into said shroud means with the discharge opening of said pipe conforming to the peripheral path of the condenser fan blades and closely overlying the same, whereby the products of combustion are induced to flow from said discharge opening to achieve a proper draft within the flue pipe.
Claim 2
Dependent Claim
119 words
In a combination heating and cooling unit comprising a housing, a cooling unit within said housing including a condenser and an assembly including a condenser fan and shroud means encompassing said fan, and a fuel burning forced air furnace including a furnace heat exchanger assembly, the improvement comprising: a flue pipe leading from said furnace heat exchanger assembly for discharging products of combustion, said flue pipe having the discharge end extending into said shroud means with the discharge opening of said pipe conforming to the peripheral path of the condenser fan blades and closely overlying the same, whereby the products of combustion are induced to flow from said discharge opening to achieve a proper draft within the flue pipe.
Claim 3
Dependent Claim
54 words
The unit as claimed in claim 1 wherein said shroud means comprises panel means positioned downstream of said condenser and carrying a circular opening for partially receiving said fan blade, and said unit further includes means for positioning the discharge end of said flue pipe adjacent to the inlet side of said panel opening.
Claim 4
Dependent Claim
22 words
The unit as claimed in claim 2 wherein the end of said flue pipe overlies the axis of rotation of said fan.
Claim 5
Dependent Claim
51 words
The unit as claimed in claim 1 further comprising a barometric draft control damper positioned within said flue pipe intermediate of said furnace heat exchanger and the discharge end of said pipe for insuring maintenance of a constant vacuum pressure within said furnace regardless of invironmental wind effects on said unit.
Claim 6
Dependent Claim
99 words
The unit as claimed in claim 4 wherein said damper comprises a cylindrical pipe intersecting said flue pipe and extending outwardly therefrom at right angles thereto, a disc valve pivotably mounted for rotation about a horizontal axis within the open end of said damper pipe, and an adjustable weight carried by said valve disc tending to maintain said valve disc in slightly open position in the absence of applied vacuum pressure to said damper pipe internally of said valve disc; whereby, adjusting said weight allows the vacuum pressure within said furnace to be varied for a given fan velocity.
Claim 7
Dependent Claim
51 words
The unit as claimed in claim 3 further comprising a barometric draft control damper positioned within said flue pipe intermediate of said furnace heat exchanger and the discharge end of said pipe for insuring maintenance of a constant vacuum pressure within said furnace regardless of environmental wind effects on said unit.
Claim 8
Dependent Claim
99 words
The unit as claimed in claim 6 wherein said damper comprises a cylindrical pipe intersecting said flue pipe and extending outwardly therefrom at right angles thereto, a disc valve pivotably mounted for rotation about a horizontal axis within the open end of said damper pipe, and an adjustable weight carried by said valve disc tending to maintain said valve disc in slightly open position in the absence of applied vacuum pressure to said damper pipe internally of said valve disc; whereby, adjusting said weight allows the vacuum pressure within said furnace to be varied for a given fan velocity.
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) | 1975-10-03 | 1976-04-03 | 1976-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-03 | 1980-04-03 | 1980-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-03 | 1984-04-03 | 1984-10-03 | $7700.00 | Window Closed / Lapsed |