Patent US3669426A successfully refreshed from Google Patents.
US3669426A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Furnaces
Assignee: Vibrantz Corp
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Filing: 1970-10-26
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Granted: 1972-06-13
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Expires: 1990-10-26
Abstract
Abstract A direct fired tunnel-type continuous heat treating furnace, particularly adapted to fire porcelain enamel articles, wherein the conventional muffle has been eliminated in favor of a system of perforate refractory shapes, so disposed to channel, and directly and evenly distribute, heat from the burners of said furnace throughout its hot zone.
Inventors
- 👤 Robert George Whitehouse
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:07
CPC Classifications
C; C23; C23D; C23D9/00; F; F27; F27B; F27B9/00; F27B9/06; F27B9/10
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
130 words
A direct fired tunnel furnace having a furnace chamber bounded by a bottom wall and a pair of opposed side walls; a plurality of main duct systems each comprising a two ended underfloor duct in said bottom wall, a main rising duct in one of said side walls disposed at an angle to said floor duct, connected directly to, and communicating directly with, one end of said underfloor duct, a plurality of flue ports in said underfloor and main rising ducts connecting said ducts to said furnAce chamber, a plurality of burners each associated with a respective one of said duct systems and arranged to discharge hot flue gases into said underfloor duct at one end thereof opposite the end connected to, and communicating directly with, said main rising duct.
Claim 2
Dependent Claim
130 words
A direct fired tunnel furnace having a furnace chamber bounded by a bottom wall and a pair of opposed side walls; a plurality of main duct systems each comprising a two ended underfloor duct in said bottom wall, a main rising duct in one of said side walls disposed at an angle to said floor duct, connected directly to, and communicating directly with, one end of said underfloor duct, a plurality of flue ports in said underfloor and main rising ducts connecting said ducts to said furnAce chamber, a plurality of burners each associated with a respective one of said duct systems and arranged to discharge hot flue gases into said underfloor duct at one end thereof opposite the end connected to, and communicating directly with, said main rising duct.
Claim 3
Dependent Claim
62 words
The tunnel furnace of claim 1 wherein said side walls are each composed of a plurality of blocks loosely assembled one on another and each having main apertures therethrough, main apertures of adjacent blocks being in register with each other to form said main rising ducts, said blocks further having side apertures therethrough intersecting said main apertures to form said flue ports.
Claim 4
Dependent Claim
44 words
The tunnel furnace of claim 1 wherein said furnace chamber is of U configuration in plan having a common partition wall in which said rising ducts are formed adjacent rising ducts being connected to respective underfloor ducts on opposite sides of said partition wall.
Claim 5
Dependent Claim
29 words
The tunnel furnace of claim 1 wherein said furnace is of the straight through type, and successive burners along said tunnel are arranged on alternate sides of said tunnel.
References Cited (Backward Citations)
US2162378A
Cited
US3091832A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-13 | 1975-12-13 | 1976-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-13 | 1983-12-13 | 1984-06-13 | $7700.00 | Window Closed / Lapsed |