Patent US2939899A successfully refreshed from Google Patents.
US2939899A
Expired / Lapsed
US
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Metal melting furnace
Assignee: Lindberg Engineering Co
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Filing: 1955-11-14
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Granted: 1960-06-07
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Expires: 1975-11-14
Abstract
No abstract record available.
Inventors
- 👤 Elmer W Edstrand
- 👤 Karl A Lang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:48
CPC Classifications
F; F27; F27B; F27B5/00; F27B5/04; F27D; F27D11/00; F27D11/06; H; H05; H05B; H05B6/00; H05B6/02; H05B6/16; H05B6/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
112 words
A METAL MELTING FURNACE COMPRISING THREE HORIZONTALLY SPACED CHAMBERS INCLUDING A CHARGING CHAMBER, A HOLDING CHAMBER AND A DISCHARGE CHAMBER, MELTING CHANNELS CONNECTING THE CHARGING AND HOLDING CHAMBERS, A PRIMARY WINDING THREADING THE METLING CHANNELS TO INDUCE A FLOW OF HEATING CURRENT THEREIN AND IN THE CHARGING AND HOLDING CHAMBERS, MEANS PROVIDING RESTRICTED COMMUNICATION BETWEEN THE CHARGING AND HOLDING CHAMBERS BELOW THE LEVEL OF MOLTEN METAL THEREIN, A RELATIVELY UNRESTRICTED DISCHARGED CONDUIT EXTENDING INTO THE DISCHARGE CHAMBER FROM THE UPPER PART THEREOF TO A POINT BELOW THE NORMAL LEVEL OF MOLTEN METAL THEREIN, AND MEANS TO PLACE THE DISCHARGE CHAMBER PERIODICALLY UNDER PRESSURE TO FORCE MOLTEN METAL THEREFROM THROUGH THE DISCHARGE CONDUIT.
Claim 2
Dependent Claim
112 words
A METAL MELTING FURNACE COMPRISING THREE HORIZONTALLY SPACED CHAMBERS INCLUDING A CHARGING CHAMBER, A HOLDING CHAMBER AND A DISCHARGE CHAMBER, MELTING CHANNELS CONNECTING THE CHARGING AND HOLDING CHAMBERS, A PRIMARY WINDING THREADING THE METLING CHANNELS TO INDUCE A FLOW OF HEATING CURRENT THEREIN AND IN THE CHARGING AND HOLDING CHAMBERS, MEANS PROVIDING RESTRICTED COMMUNICATION BETWEEN THE CHARGING AND HOLDING CHAMBERS BELOW THE LEVEL OF MOLTEN METAL THEREIN, A RELATIVELY UNRESTRICTED DISCHARGED CONDUIT EXTENDING INTO THE DISCHARGE CHAMBER FROM THE UPPER PART THEREOF TO A POINT BELOW THE NORMAL LEVEL OF MOLTEN METAL THEREIN, AND MEANS TO PLACE THE DISCHARGE CHAMBER PERIODICALLY UNDER PRESSURE TO FORCE MOLTEN METAL THEREFROM THROUGH THE DISCHARGE CONDUIT.
References Cited (Backward Citations)
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Cited
US1026733A
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US1736188A
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US2210544A
Cited
US2707718A
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US2648715A
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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) | 1963-06-07 | 1963-12-07 | 1964-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-06-07 | 1967-12-07 | 1968-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-06-07 | 1971-12-07 | 1972-06-07 | $7700.00 | Window Closed / Lapsed |