Patent US4707451A successfully refreshed from Google Patents.
Patent US3670801A successfully refreshed from Google Patents.
US3670801A
Expired / Lapsed
US
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Continuous casting mold level control
Assignee: GLENFED CAPITAL CORP
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Filing: 1970-01-16
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Granted: 1972-06-20
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Expires: 1990-01-16
Abstract
Abstract A molten metal continuous casting mold level control system is disclosed employing an inductance detector positioned within a water cooled continuous casting mold. The detector is mounted in the jacket of the mold about the generally hollow cylindrical mold core which core includes an electrically conductive form having a billet shaping surface. The output voltage from the detector is bucked against a signal that is related to an input signal, filtered and amplified to derive a signal whose polarity from a reference level and magnitude are proportionate to the direction and magnitude of change in the steel level. This signal is used to control the billet drive to correct changes from the desired level.
Inventors
- 👤 Jack R Crowell
- 👤 James R Tomashek
- 👤 Donald H Ward
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:00
CPC Classifications
B; B22; B22D; B22D11/00; B22D11/16; B22D11/20; B22D11/201; B22D11/205; G; G01; G01F; G01F23/00; G01F23/22; G01F23/26; G05; G05D; G05D9/00; G05D9/12
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
308 words
In a mold level control system for controlling the level of molten metal in a continuous casting mold of the type that has a core defining a shaping surface, which core includes a layer of highly conductive material and which mold receives molten metal from a source and from which a continuous billet of at least partly hardened metal is extracted by a variable speed drive system, the improvement of having: an inductance mold level detector, including at least one inductance coil, which detector is positioned adjacent to but without the mold core, for detecting variations in the level of molten metal therein; means coupled to said mold level detector and to the billet drive system for controlling the speed of the billet drive system in response to said detector so as to vary the speed thereof to maintain, during normal operation, the level of the molten metal within a desired predetermined range; said inductance mold level detector comprising two coils, said one coil and a second coil; and said controlling means including: a signal source coupled to said one coil for exciting it with an ac input signal, means coupled to said second coil for deriving an output signal therefrom which is related to the input signal and to the level of molten metal in the mold; a source of a second signal related to the input signal but phase shifted therefrom, and means coupled to said output signal deriving means and said second signal source for deriving a dc mold level control signal whose amplitude varies in proportion with changes in the level of molten metal in the mold core from a predetermined level therein; whereby the mold level control signal may be employed to govern the operation of motors in the billet drive system to counter changes in the molten metal from the predetermined level.
Claim 2
Dependent Claim
308 words
In a mold level control system for controlling the level of molten metal in a continuous casting mold of the type that has a core defining a shaping surface, which core includes a layer of highly conductive material and which mold receives molten metal from a source and from which a continuous billet of at least partly hardened metal is extracted by a variable speed drive system, the improvement of having: an inductance mold level detector, including at least one inductance coil, which detector is positioned adjacent to but without the mold core, for detecting variations in the level of molten metal therein; means coupled to said mold level detector and to the billet drive system for controlling the speed of the billet drive system in response to said detector so as to vary the speed thereof to maintain, during normal operation, the level of the molten metal within a desired predetermined range; said inductance mold level detector comprising two coils, said one coil and a second coil; and said controlling means including: a signal source coupled to said one coil for exciting it with an ac input signal, means coupled to said second coil for deriving an output signal therefrom which is related to the input signal and to the level of molten metal in the mold; a source of a second signal related to the input signal but phase shifted therefrom, and means coupled to said output signal deriving means and said second signal source for deriving a dc mold level control signal whose amplitude varies in proportion with changes in the level of molten metal in the mold core from a predetermined level therein; whereby the mold level control signal may be employed to govern the operation of motors in the billet drive system to counter changes in the molten metal from the predetermined level.
Claim 3
Dependent Claim
217 words
A continuous steel casting system comprising: a source (12) of molten steel; a mold unit (20) having a generally vertical core including an integral electrically conductive form defining a shaping surface (20A) into which form said source pours molten steel at an approximately constant and continuous rate, and a jacket about said form in which an electrically conducting coolant is circulated and from which mold unit a continuous steel billet is produced; an inductance level detector (30) positioned in said jacket adjacent to but outside of said core substantially surrounded by said circulating electrically conducting coolant to detect the level of molten steel in the form; a billet drive system (16) that is responsive to a drive control signal to vary the rate of removal of the billet from the mold unit; a source (41) of excitation signals coupled to said inductance detector; and means (40, 47, 24, 22) coupled to said inductance level detector for extracting therefrom a signal indicative of the level of molten steel and for determining therefrom a variable drive control signal therefrom, and for coupling that control signal to said billet drive system; whereby a change in the level of molten steel results in a change in the rate of billet extraction so as to restore the level to a predetermined level.
Claim 4
Dependent Claim
217 words
A continuous steel casting system comprising: a source (12) of molten steel; a mold unit (20) having a generally vertical core including an integral electrically conductive form defining a shaping surface (20A) into which form said source pours molten steel at an approximately constant and continuous rate, and a jacket about said form in which an electrically conducting coolant is circulated and from which mold unit a continuous steel billet is produced; an inductance level detector (30) positioned in said jacket adjacent to but outside of said core substantially surrounded by said circulating electrically conducting coolant to detect the level of molten steel in the form; a billet drive system (16) that is responsive to a drive control signal to vary the rate of removal of the billet from the mold unit; a source (41) of excitation signals coupled to said inductance detector; and means (40, 47, 24, 22) coupled to said inductance level detector for extracting therefrom a signal indicative of the level of molten steel and for determining therefrom a variable drive control signal therefrom, and for coupling that control signal to said billet drive system; whereby a change in the level of molten steel results in a change in the rate of billet extraction so as to restore the level to a predetermined level.
Claim 5
Dependent Claim
95 words
The invention of claim 2, wherein: said inductance level detector within said mold unit includes two coils, a primary coil and a secondary coil; said source of excitation signals are coupled to said primary coil; said means for extracting a signal from said inductance level detector and for determining a control signal therefrom is coupled to said secondary coil and includes means for producing a second signal related to but altered from said excitation signal and means for combining the extracted signal from said secondary coil and said second signal to produce the control signal.
Claim 6
Dependent Claim
212 words
A continuous metal casting system comprising: a source (12) of molten metal; a mold unit (20) having a generally vertical, integral and electrically conductive form, which form defines a shaping Surface (20A) and into which form said source pours molten metal and from which form a continuous steel billet is produced, and a jacket about said form in which an electrically conducting coolant is circulated; an inductance level detector (30), positioned in said jacket adjacent to but outside of said form and substantially surrounded by said circulating coolant, to detect the level of molten metal in the form; a billet drive system (16) that is responsive to a drive control signal to vary the rate of removal of the billet from said form; a source (41) of excitation signals coupled to said inductance detector; and means (40, 47, 24, 22) coupled to said inductance level detector for extracting therefrom a signal indicative of the level of molten metal and for determining therefrom a variable drive control signal, and for coupling that control signal to said billet drive system; whereby a change in the level of molten metal from a predetermined level results in a change in the rate of billet extraction so as to restore the molten metal to that predetermined level.
Claim 7
Dependent Claim
212 words
A continuous metal casting system comprising: a source (12) of molten metal; a mold unit (20) having a generally vertical, integral and electrically conductive form, which form defines a shaping Surface (20A) and into which form said source pours molten metal and from which form a continuous steel billet is produced, and a jacket about said form in which an electrically conducting coolant is circulated; an inductance level detector (30), positioned in said jacket adjacent to but outside of said form and substantially surrounded by said circulating coolant, to detect the level of molten metal in the form; a billet drive system (16) that is responsive to a drive control signal to vary the rate of removal of the billet from said form; a source (41) of excitation signals coupled to said inductance detector; and means (40, 47, 24, 22) coupled to said inductance level detector for extracting therefrom a signal indicative of the level of molten metal and for determining therefrom a variable drive control signal, and for coupling that control signal to said billet drive system; whereby a change in the level of molten metal from a predetermined level results in a change in the rate of billet extraction so as to restore the molten metal to that predetermined level.
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) | 1975-06-20 | 1975-12-20 | 1976-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-20 | 1979-12-20 | 1980-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-20 | 1983-12-20 | 1984-06-20 | $7700.00 | Window Closed / Lapsed |