US4403328A
Expired / Lapsed
US
⏱️ 0.0 years remaining
DC Arc furnace power connection system
Assignee: ABB Norden Holding AB
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Filing: 1982-02-17
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Granted: 1983-09-06
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Expires: 2002-02-17
Abstract
Abstract A DC arc furnace has power lines arranged completely symmetrically with respect to the arc so as to prevent the arc from bending angularly.
Inventors
- 👤 Erik Lassander
- 👤 Sven-Einar Stenkvist
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:58
CPC Classifications
C; C21; C21C; C21C5/00; C21C5/52; C21C5/5229; H; H05; H05B; H05B7/00; H05B7/02; H05B7/11; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
199 words
A DC arc furnace having a removable roof through which an arcing electrode depends via a horizontal electrode arm extending over the roof from a location offset from the roof, roof-removing equipment including a horizontal frame having an end at said location and extending over the roof to an end beyond the opposite side of the roof via frame sides spaced on either side of said electrode, and a melt connection having terminals extending from the bottom of the furnace below the frame's ends; wherein the improvement comprises positive and negative DC power lines extending together to said location, the negative line connecting with a first conductor extending from said location straight to connection with said electrode via said electrode arm, and the positive line connecting with a second conductor extending downwardly from said location to connection with the one of said terminals therebelow and with a third conductor forming a closed loop around said electrode via the ends and sides of said frame, the loop having one end with which the positive line directly connects at said location and an opposite end from which a fourth conductor extends downwardly to connection with the one of said terminals therebelow.
Claim 2
Dependent Claim
199 words
A DC arc furnace having a removable roof through which an arcing electrode depends via a horizontal electrode arm extending over the roof from a location offset from the roof, roof-removing equipment including a horizontal frame having an end at said location and extending over the roof to an end beyond the opposite side of the roof via frame sides spaced on either side of said electrode, and a melt connection having terminals extending from the bottom of the furnace below the frame's ends; wherein the improvement comprises positive and negative DC power lines extending together to said location, the negative line connecting with a first conductor extending from said location straight to connection with said electrode via said electrode arm, and the positive line connecting with a second conductor extending downwardly from said location to connection with the one of said terminals therebelow and with a third conductor forming a closed loop around said electrode via the ends and sides of said frame, the loop having one end with which the positive line directly connects at said location and an opposite end from which a fourth conductor extends downwardly to connection with the one of said terminals therebelow.
Claim 3
Dependent Claim
24 words
The furnace of claim 1 in which said terminals and said second, third and fourth conductors are symmetrically disposed with respect to said electrode.
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) | 1986-09-05 | 1987-03-07 | 1987-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-05 | 1991-03-07 | 1991-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-05 | 1995-03-07 | 1995-09-06 | $7700.00 | Window Closed / Lapsed |