US3385920A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system for consumable electrode furnace
Assignee: Allegheny Ludlum Steel Corp
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Filing: 1965-10-01
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Granted: 1968-05-28
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Expires: 1985-10-01
Abstract
No abstract record available.
Inventors
- 👤 Samuel S Harbaugh
- 👤 Donald C Mccarter
- 👤 Peter A Lajoie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:41
CPC Classifications
H; H05; H05B; H05B7/00; H05B7/005; C; C22; C22B; C22B9/00; C22B9/16; C22B9/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
149 words
IN A CONSUMABLE ELECTRODE FURNACE OF THE TYPE IN WHICH AN ARC IS STRUCK BETWEEN A CONSUMABLE ELECTRODE AND A MOLTEN POOL OF METAL BENEATH IT AND IN WHICH AN ELECTRICALLY-CONTROLLED MOTOR DEVICE IS EMPLOYED TO MOVE THE ELECTRODE DOWNWARDLY TOWARD THE MOLTEN POOL AS IT IS CONSUMED; THE COMBINATION OF MEANS FOR PRODUCING AN ELECTRICAL SIGNAL WHICH VARIES NON-LINEARLY AS A FUNCTION OF THE SPACING BETWEEN THE ELECTRODE AND SAID MOLTEN POOL, MEANS FOR CONTROLLING SAID MOTOR DEVICE IN RESPONSE TO CHANGES IN SAID ELECTRICAL SIGNAL IN A SERVO-LOOP ARRANGEMENT, THE ELECTRICAL SIGNAL HAVING A HIGH GAIN FACTOR AS ITS MAGNITUDE INCREASES DUE TO SAID NON-LINEARITY, AND MEANS FOR SUPERIMPOSING ON SAID ELECTRICAL SIGNAL AN AUXILIARY SIGNAL OF MAGNITUDE SUFFICIENT TO PERMIT THE SERVO LOOP TO OPERATE AT A LOWER GAIN FACTOR FOR A GIVEN RATE OF MOVEMENT OF THE ELECTRODE THAN IT WOULD WITHOUT THE AUXILIARY SIGNAL.
Claim 2
Dependent Claim
149 words
IN A CONSUMABLE ELECTRODE FURNACE OF THE TYPE IN WHICH AN ARC IS STRUCK BETWEEN A CONSUMABLE ELECTRODE AND A MOLTEN POOL OF METAL BENEATH IT AND IN WHICH AN ELECTRICALLY-CONTROLLED MOTOR DEVICE IS EMPLOYED TO MOVE THE ELECTRODE DOWNWARDLY TOWARD THE MOLTEN POOL AS IT IS CONSUMED; THE COMBINATION OF MEANS FOR PRODUCING AN ELECTRICAL SIGNAL WHICH VARIES NON-LINEARLY AS A FUNCTION OF THE SPACING BETWEEN THE ELECTRODE AND SAID MOLTEN POOL, MEANS FOR CONTROLLING SAID MOTOR DEVICE IN RESPONSE TO CHANGES IN SAID ELECTRICAL SIGNAL IN A SERVO-LOOP ARRANGEMENT, THE ELECTRICAL SIGNAL HAVING A HIGH GAIN FACTOR AS ITS MAGNITUDE INCREASES DUE TO SAID NON-LINEARITY, AND MEANS FOR SUPERIMPOSING ON SAID ELECTRICAL SIGNAL AN AUXILIARY SIGNAL OF MAGNITUDE SUFFICIENT TO PERMIT THE SERVO LOOP TO OPERATE AT A LOWER GAIN FACTOR FOR A GIVEN RATE OF MOVEMENT OF THE ELECTRODE THAN IT WOULD WITHOUT THE AUXILIARY SIGNAL.
References Cited (Backward Citations)
US3187077A
Cited
US3187078A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-05-28 | 1971-11-27 | 1972-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-05-28 | 1975-11-27 | 1976-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-05-28 | 1979-11-27 | 1980-05-28 | $7700.00 | Window Closed / Lapsed |