US4110546A
Expired / Lapsed
US
⏱️ 0.0 years remaining
DC arc furnace having a rotating arc
Assignee: ABB Norden Holding AB
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Filing: 1976-11-05
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Granted: 1978-08-29
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Expires: 1996-11-05
Abstract
Abstract A DC electric arc furnace with a furnace enclosure having a hearth containing a melt and with an arcing electrode forming an arc with the melt and made to angularly deflect and rotate by magnetic means forming a rotating magnetic field in the enclosure, is provided with means for sensing areas of the enclosure receiving a maximum intensity of arc radiation because of an asymmetrical charge in the furnace, this sensing means controlling the speed of rotation of the arc so that the arc rotates faster while directing its arc flare at these areas receiving maximum radiation.
Inventors
- 👤 Sven-Einar Stenkvist
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:34
CPC Classifications
H; H05; H05B; H05B7/00; H05B7/02; C; C21; C21C; C21C5/00; C21C5/52; C21C5/5229; F; F27; F27D; F27D11/00; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
122 words
A DC electric arc furnace comprising a furnace enclosure having a hearth for containing a melt, an arcing electrode positioned in the enclosure above the melt and forming an arc therewith when the electrode and melt are placed in circuit with a source of DC, magnetic means for forming a rotating magnetic field in the enclosure causing the arc to rotatively deflect, and means for varying the rotative speed of said arc while the arc rotates through any one complete rotation so as to cause said speed to be relatively fast when said arc is deflected towards relatively hot portions of said enclosure and said speed to be relatively slow when said arc is deflected towards relatively cold portions of the enclosure.
Claim 2
Dependent Claim
122 words
A DC electric arc furnace comprising a furnace enclosure having a hearth for containing a melt, an arcing electrode positioned in the enclosure above the melt and forming an arc therewith when the electrode and melt are placed in circuit with a source of DC, magnetic means for forming a rotating magnetic field in the enclosure causing the arc to rotatively deflect, and means for varying the rotative speed of said arc while the arc rotates through any one complete rotation so as to cause said speed to be relatively fast when said arc is deflected towards relatively hot portions of said enclosure and said speed to be relatively slow when said arc is deflected towards relatively cold portions of the enclosure.
Claim 3
Dependent Claim
28 words
The furnace of claim 1 having means for causing said rotative speed to be responsive to the enclosure's temperature at at least one location of the enclosure's periphery.
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) | 1981-08-28 | 1982-02-27 | 1982-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-08-28 | 1986-02-27 | 1986-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-08-28 | 1990-02-27 | 1990-08-29 | $7700.00 | Window Closed / Lapsed |