US3683653A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Motor drive system for rolling mill
Assignee: General Electric Co
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Filing: 1971-02-22
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Granted: 1972-08-15
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Expires: 1991-02-22
Abstract
Abstract In a four high rolling mill having two powered working rolls and a pair of backup rolls, the backup rolls are synchronized by controlling the drive motors to force differential slippage between the working rolls and the strip being processed through the mill. Angular position comparison means senses and lack of synchronism of the backup rolls and produces a control signal which differentially adjusts the torques produced by the drive motors. Synchronization of the backup rolls reduces roll force variations caused by eccentricity of rolls.
Inventors
- 👤 Howard Nesbit Cox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 01:54
CPC Classifications
B; B21; B21B; B21B37/00; B21B37/58; B21B37/66; B21B37/46
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
197 words
A drive system for a rolling mill comprising a pair of engaging working rolls having an interface through which a strip to be rolled passes, and a pair of backup rolls, each backup roll engaging its associated working roll on opposite sides of said interface and being rotatably driven with the working roll, said system comprising: a. a pair of motors for driving the working and backup rolls, each motor being separately connected to drive its associated working and backup rolls, b. control means for differentially adjusting the torques applied to the working rolls by the drive motors, c. comparator means arranged continuously to compare the instantaneous angular positions of the backup rolls and produce an output signal variable in accordance with deviation of the relative angular positions of the backup rolls from a predetermined position, and d. coupling means activating said control means in accordance with the output signal from said comparator means whereby the relative magnitudes of the torques applied to the working rolls are adjusted to cause differential slip to occur between the working rolls at said interface to maintain the backup rolls in said predetermined relative angular position during operation of the mill.
Claim 2
Dependent Claim
197 words
A drive system for a rolling mill comprising a pair of engaging working rolls having an interface through which a strip to be rolled passes, and a pair of backup rolls, each backup roll engaging its associated working roll on opposite sides of said interface and being rotatably driven with the working roll, said system comprising: a. a pair of motors for driving the working and backup rolls, each motor being separately connected to drive its associated working and backup rolls, b. control means for differentially adjusting the torques applied to the working rolls by the drive motors, c. comparator means arranged continuously to compare the instantaneous angular positions of the backup rolls and produce an output signal variable in accordance with deviation of the relative angular positions of the backup rolls from a predetermined position, and d. coupling means activating said control means in accordance with the output signal from said comparator means whereby the relative magnitudes of the torques applied to the working rolls are adjusted to cause differential slip to occur between the working rolls at said interface to maintain the backup rolls in said predetermined relative angular position during operation of the mill.
Claim 3
Dependent Claim
35 words
A drive system as set forth in claim 1 wherein the motors have fields supplied with adjustable current and the control means comprises means for differentially adjusting the field currents supplied to the drive motors.
Claim 4
Dependent Claim
47 words
A drive system as set forth in claim 1 wherein the comparator means is a selsyn system comprising a differential selsyn having stator and rotor windings energized by selsyn generators coupled to the backup rolls, the mechanical deflection of the differential selsyn rotor constituting the output signal.
Claim 5
Dependent Claim
34 words
A drive system as set forth in claim 1 including disconnect means for disabling the control means until the backup rolls acquire said predetermined relative angular position during rotation thereof by the drive motors.
Claim 6
Dependent Claim
25 words
A drive system as set forth in claim 3 including a clutch interposed between the mechanical output of the differential selsyn and the control means.
Claim 7
Dependent Claim
35 words
A drive system as set forth in claim 1 wherein each drive motor has a separate field current regulator and the control means comprises means for differentially adjusting the outputs of the field current regulators.
Claim 8
Dependent Claim
38 words
A drive system as set forth in claim 6 wherein the means for differentially adjusting the output of the field current regulators includes a circuit energized from the output of an integrating amplifier controlled by said comparator means.
Claim 9
Dependent Claim
43 words
A drive system as set forth in claim 7 including means for supplying the integrating amplifier with an input signal the magnitude and polarity of which is varied in accordance with the direction and magnitude of the output signal from the comparator means.
Claim 10
Dependent Claim
48 words
A drive system as set forth in claim 8 wherein the comparator means is a selsyn system comprising a differential selsyn having rotor and stator windings energized by selsyn generators coupled to the backup rolls, the mechanical deflection of the differential selsyn rotor constituting the comparator output signal.
Claim 11
Dependent Claim
21 words
A drive system as set forth in claim 9 including a clutch interposed between the differential selsyn and the control means.
References Cited (Backward Citations)
US3331229A
Cited
US3298212A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-15 | 1976-02-14 | 1976-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-15 | 1980-02-14 | 1980-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-15 | 1984-02-14 | 1984-08-15 | $7700.00 | Window Closed / Lapsed |