US3769440A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Current monitoring system for electric arc furnace conductors
Assignee: Individual
•
Filing: 1972-09-27
•
Granted: 1973-10-30
•
Expires: 1992-09-27
Abstract
Abstract Each conductor cable of the set of conductor cables for each phase, extending from the furnace transformer to the electric arc furnace, is encircled by an annular close-wound current transformer coil, the terminals of which are connected to a lowvoltage voltmeter. All of the voltmeters for each phase are interconnected and in turn are connected to an integrating network, the output of which is connected to a terminal strip or block for further connection to a suitable recording instrument. Each voltmeter may, if desired, be provided with an additional audible or visual signal device. If any furnace conductor, cable is for any reason carrying less than its proportion of the current, thereby reflecting a deterioration of that particular cable, that condition is immediately indicated by a lowered voltage reading on its particular voltmeter, so that the operator can take immediate corrective action.
Inventors
- 👤 D Goodman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 16:04
CPC Classifications
G; G01; G01R; G01R15/00; G01R15/14; G01R15/18; G01R15/181; F; F27; F27D; F27D11/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
136 words
A monitoring system for indicating the current-carrying condition of each of the individual furnace conductor cables connecting a multi-phase electric arc furnace transformer to an electric arc furnace, said system comprising a monitoring current transformer coil encircling each furnace current conductor cable of each phase, said coil being responsive to the flow of furnace transformer current through its respective furnace current conductor cable to effect flow of induced current through said coil, each coil including a winding wound on a core encircling its respective furnace current conductor cable, and a voltmeter so connected to each coil as to indicate the voltage of said induced current flowing through said coil, whereby to immediately detect any adverse current flow condition in any conductor cable at any desired time and thereby to enable remedying said adverse condition at once.
Claim 2
Dependent Claim
136 words
A monitoring system for indicating the current-carrying condition of each of the individual furnace conductor cables connecting a multi-phase electric arc furnace transformer to an electric arc furnace, said system comprising a monitoring current transformer coil encircling each furnace current conductor cable of each phase, said coil being responsive to the flow of furnace transformer current through its respective furnace current conductor cable to effect flow of induced current through said coil, each coil including a winding wound on a core encircling its respective furnace current conductor cable, and a voltmeter so connected to each coil as to indicate the voltage of said induced current flowing through said coil, whereby to immediately detect any adverse current flow condition in any conductor cable at any desired time and thereby to enable remedying said adverse condition at once.
Claim 3
Dependent Claim
14 words
A monitoring system, according to claim 1, wherein said core is of non-magnetic material.
Claim 4
Dependent Claim
14 words
A monitoring system, according to claim 1, wherein said core is of toroidal configuration.
Claim 5
Dependent Claim
24 words
A monitoring system, according to claim 3, wherein said winding is also of toroidal configuration and has its convolutions closely wound upon said core.
Claim 6
Dependent Claim
15 words
A monitoring system, according to claim 1, wherein said voltmeter is an alternating current voltmeter.
Claim 7
Dependent Claim
16 words
A monitoring system, according to claim 1, wherein an integrating network is connected to said voltmeter.
Claim 8
Dependent Claim
51 words
A monitoring system, according to claim 1, wherein all of the voltmeters for the monitoring current transformer coils encircling the furnace current conductor cables of each phase are connected to one another in a circuit, and wherein the output of said circuit is connected to the input of an integrating network.
Claim 9
Dependent Claim
22 words
A monitoring system, according to claim 7 wherein a current characteristics indicating instrument is connected to the output of said integrating network.
Claim 10
Dependent Claim
30 words
A monitoring system, according to claim 8, wherein the current characteristics indicating instrument is a dual channel recorder indicating the variation of volts and amperes in the current passing therethrough.
References Cited (Backward Citations)
US1214763A
Cited
US1532599A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-29 | 1977-04-30 | 1977-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-29 | 1981-04-30 | 1981-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-29 | 1985-04-30 | 1985-10-30 | $7700.00 | Window Closed / Lapsed |