US4491952A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric furnace dome
Assignee: Outokumpu Oyj
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Filing: 1982-06-03
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Granted: 1985-01-01
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Expires: 2002-06-03
Abstract
Abstract Electric furnace dome that is made especially of ceramic material and which has the necessary openings for at least electrodes and material feed, at which time the dome's center (2) inside of the tube systems (3) is cooled at least around the openings with the aid of spiral tube systems (5,7,8,9) whose tube systems (3,5,7,8,9) form a part of the dome's support system.
Inventors
- 👤 Matti Honkaniemi
- 👤 Martti Jankkila
- 👤 Aimo Nurminen
- 👤 Matias Virta
- 👤 Veikko Iisakka
- 👤 Helge Krogerus
- 👤 Heikki Tuovinen
- 👤 Tarmo Mantymaki
- 👤 Erkki Lajunen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:22
CPC Classifications
F; F27; F27D; F27D1/00; F27D1/18; F27D1/1808; F27D1/1816
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
81 words
In an electric furnace dome having top and bottom surfaces, and having at least one opening for an electrode, the improvement comprising (a) a water-carrying spiral tube system embedded between said surfaces for water-cooling the dome and centered around said electrode opening, and (b) means for supplying cooling water to said spiral tube system and for supporting the dome, said means including a portion of said spiral tube system that extends upwardly and away from said top surface of the dome.
Claim 2
Dependent Claim
81 words
In an electric furnace dome having top and bottom surfaces, and having at least one opening for an electrode, the improvement comprising (a) a water-carrying spiral tube system embedded between said surfaces for water-cooling the dome and centered around said electrode opening, and (b) means for supplying cooling water to said spiral tube system and for supporting the dome, said means including a portion of said spiral tube system that extends upwardly and away from said top surface of the dome.
Claim 3
Dependent Claim
126 words
In an electric furnace dome having top and bottom surfaces and respective openings at least for one electrode, for the insertion of raw material, and for the exhaust of gases, and having a central portion and an outer portion, said electrode opening being in said central portion, the improvement comprising (a) water-carrying spiral tube systems embedded between said surfaces for water-cooling the dome, located only in said central portion, and at least one spiral tube system being centered around each opening in said central portion; and (b) means for supplying cooling water to said spiral tube systems and for supporting the dome, said means including a portion of each of said spiral tube systems that extends upwardly and away from said top surface of the dome.
Claim 4
Dependent Claim
126 words
In an electric furnace dome having top and bottom surfaces and respective openings at least for one electrode, for the insertion of raw material, and for the exhaust of gases, and having a central portion and an outer portion, said electrode opening being in said central portion, the improvement comprising (a) water-carrying spiral tube systems embedded between said surfaces for water-cooling the dome, located only in said central portion, and at least one spiral tube system being centered around each opening in said central portion; and (b) means for supplying cooling water to said spiral tube systems and for supporting the dome, said means including a portion of each of said spiral tube systems that extends upwardly and away from said top surface of the dome.
Claim 5
Dependent Claim
16 words
An electric furnace dome as in claim 2, wherein said dome is made of ceramic material.
Claim 6
Dependent Claim
32 words
An electric furnace dome as in claim 2, further comprising a second water-carrying tube system embedded between said surfaces and surrounding said central portion of the dome, for further water-cooling the dome.
Claim 7
Dependent Claim
20 words
An electric furnace dome as in claim 4, wherein said dome and said second water-carrying tube system are substantially circular.
Claim 8
Dependent Claim
63 words
An electric furnace dome as in claim 2, further comprising at least one water seal mounted on said central portion of said dome for sealing and water-cooling said electrode opening, and wherein said means for supplying cooling water are connected to said water seal so as to circulate the same water sequentially through said seal and at least one of said tube systems.
References Cited (Backward Citations)
DE1065540B
Cited
US2222004A
Cited
FR1077734A
Cited
US2718537A
Cited
US2752410A
Cited
US2871278A
Cited
GB898532A
Cited
US3129274A
Cited
US3375317A
Cited
US3429973A
Cited
US4197422A
Cited
US4273949A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-01-01 | 1988-07-02 | 1989-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-01-01 | 1992-07-02 | 1993-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-01-01 | 1996-07-02 | 1997-01-01 | $7700.00 | Window Closed / Lapsed |