US3219331A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat treating furnace
Assignee: Illinois National Bank and Trust Co
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Filing: 1961-12-18
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Granted: 1965-11-23
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Expires: 1981-12-18
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:03
CPC Classifications
C; C21; C21D; C21D1/00; C21D1/74; C21D1/773; F; F27; F27B; F27B5/00; F27B5/06; F27B2005/062; F27B2005/064; F27B5/14; F27B2005/143; F27B5/16; F27B2005/161; F27B2005/162; F27B2005/166; F27B2005/167
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
143 words
IN A HEAT TREATING FURNACE, THE COMBINATION OF, AN AIRTIGHT HOLLOW VESSEL, A WALLED ENCLOSURE SUPPORTED WITHIN SAID VESSEL IN SPACED RELATION WITH THE INNER WALLS THEREOF AND DEFINING A SUBSTANTIALLY ENCLOSED WORK CHAMBER WITHIN SAID ENCLOSURE AND AN OUTER CHAMBER BETWEEN THE ENCLOSURE AND THE VESSEL, SELECTIVELY OPERABLE MEANS FOR EVACUATING SAID VESSEL AND SAID WORK CHAMBER, A SELECTIVELY OPERABLE RADIANT HEATER IN SAID WORK CHAMBER FOR HEATING A WORKPIECE THEREIN, THE WALLS OF SAID ENCLOSURE HAVING PANELS ON THE INNER SURFACES THEREOF FOR REFLECTING RADIATION BACK TOWARD THE WORKPIECE AND ALSO HAVING A LAYER OF INSULATING MATERIAL ON THE OUTER SIDES OF SAID PANELS TO REDUCE HEAT CONDUCTION THERETHROUGH, SAID ENCLOSURE HAVING SPACED INLET AND OUTLET OPENINGS COMMUNICATING BETWEEN SAID CHAMBERS, BAFFLES OVERLYING SAID OPENINGS TO BLOCK RADIATION THERETHROUGH WHILE DEFINING INDIRECT PASSAGES FOR A FLOW OF GAS BETWEEN SAID CHAMBERS,
Claim 2
Dependent Claim
143 words
IN A HEAT TREATING FURNACE, THE COMBINATION OF, AN AIRTIGHT HOLLOW VESSEL, A WALLED ENCLOSURE SUPPORTED WITHIN SAID VESSEL IN SPACED RELATION WITH THE INNER WALLS THEREOF AND DEFINING A SUBSTANTIALLY ENCLOSED WORK CHAMBER WITHIN SAID ENCLOSURE AND AN OUTER CHAMBER BETWEEN THE ENCLOSURE AND THE VESSEL, SELECTIVELY OPERABLE MEANS FOR EVACUATING SAID VESSEL AND SAID WORK CHAMBER, A SELECTIVELY OPERABLE RADIANT HEATER IN SAID WORK CHAMBER FOR HEATING A WORKPIECE THEREIN, THE WALLS OF SAID ENCLOSURE HAVING PANELS ON THE INNER SURFACES THEREOF FOR REFLECTING RADIATION BACK TOWARD THE WORKPIECE AND ALSO HAVING A LAYER OF INSULATING MATERIAL ON THE OUTER SIDES OF SAID PANELS TO REDUCE HEAT CONDUCTION THERETHROUGH, SAID ENCLOSURE HAVING SPACED INLET AND OUTLET OPENINGS COMMUNICATING BETWEEN SAID CHAMBERS, BAFFLES OVERLYING SAID OPENINGS TO BLOCK RADIATION THERETHROUGH WHILE DEFINING INDIRECT PASSAGES FOR A FLOW OF GAS BETWEEN SAID CHAMBERS,
References Cited (Backward Citations)
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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) | 1968-11-22 | 1969-05-24 | 1969-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-22 | 1973-05-24 | 1973-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-22 | 1977-05-24 | 1977-11-23 | $7700.00 | Window Closed / Lapsed |