US3777524A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for cold rolling mill gauge deviation correction
Assignee: AEG Westinghouse Industrial Automation Corp
•
Filing: 1972-07-21
•
Granted: 1973-12-11
•
Expires: 1992-07-21
Abstract
Abstract Mill spring constant change signals are produced after each of a series of screwdown regulation cycles where each change signal is produced as a function of the ratio of the gauge deviation remaining after the regulation cycle, to the change in rolling force which occurred during the regulation cycle. The series of ratio change signals are then averaged to produce a mill spring constant correction signal which is used to correct the previously established mill spring constant. The corrected mill spring constant is then used to generate a new screwdown reference signal for the next series of regulation cycles. Provision is made to limit check and average gauge deviation so that the mill spring corrections are only made when certain predetermined gauge deviation limits are exceeded.
Inventors
- 👤 A Silva
- 👤 R Danehy
- 👤 B Kitchell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:43
CPC Classifications
B; B21; B21B; B21B37/00; B21B37/58; B21B37/64; B21B37/16; B21B2271/00; B21B2271/02
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
93 words
The method of rolling a strip of ductile material to produce a predetermined output gauge comprising measuring gauge deviations remaining after each of a series of screwdown regulation cycles; producing a corresponding series of ratio signals after each occurrence of a zero error signal in a preceding regulation cycle, where each ratio signal is produced by dividing the remaining gauge deviation by the change of roll force which occurred during the preceding regulation cycle; and averaging the ratio signals to produce a mill spring correction signal for the next series of regulation cycles.
Claim 2
Independent Claim
93 words
The method of rolling a strip of ductile material to produce a predetermined output gauge comprising measuring gauge deviations remaining after each of a series of screwdown regulation cycles; producing a corresponding series of ratio signals after each occurrence of a zero error signal in a preceding regulation cycle, where each ratio signal is produced by dividing the remaining gauge deviation by the change of roll force which occurred during the preceding regulation cycle; and averaging the ratio signals to produce a mill spring correction signal for the next series of regulation cycles.
Claim 3
Dependent Claim
38 words
The method of claim 1 wherein each ratio signal is generated after the strip has moved from the point of rolling to the point of deviation measurement spaced from said point of rolling by a predetermined transport distance.
Claim 4
Dependent Claim
63 words
The method of claim 1 wherein the regulation cycle is controlled according to a reference signal produced as a function of the initial screwdown position at the start of a regulation cycle, the gauge deviation existing at the beginning of the cycle, and the product of mill spring constant times the change of roll force necessary to reduce the error signal to zero.
Claim 5
Dependent Claim
60 words
The method of claim 3 wherein said reference signal is defined as REF SO + XAVG + KM(FA - FO) where SO is the initial screwdown position; XAVG is an averaged XRAY deviation signal; KM is the last corrected mill spring constant; FO is tHe initial rolling force and FA is the measured rolling force during the screwdown regulation cycle.
Claim 6
Dependent Claim
57 words
The method of claim 4 wherein said ratio signal is represented by the function DKM XO/DF where DKM represents a change in mill spring constant that is to be electrically averaged, XO is the gauge deviation remaining after the last regulation cycle and DF represents the change of roll force which occurred during the last regulation cycle.
Claim 7
Dependent Claim
23 words
The method of claim 3 wherein each regulation cycle is continued until REF - SA 0, where SA represents the actual screwdown position.
Claim 8
Dependent Claim
40 words
The method of claim 5 wherein said averaging step is performed by performing the summation of signal DKM a number of times and then by dividing the final summation by the number to produce said mill spring constant correction signal.
Claim 9
Dependent Claim
133 words
In a system for automatically controlling the gauge of a strip of material rolled through a mill stand, where a position regulator receives a screwdown reference signal and a signal representing the actual screwdown position and responds thereto to adjust the rolling force until the error between the reference signal and the position signal is substantially zero, a gauge deviation correction control comprising: first means for measuring the gauge deviation at a predetermined transport distance from the rolling stand; second means operative each time after said position regulator has produced a substantially zero error signal and after the strip element then has moved through said predetermined transport distance to said second means for producing a mill spring constant correction signal proportional to the average summation of gauge deviation divided by roll force change.
Claim 10
Dependent Claim
133 words
In a system for automatically controlling the gauge of a strip of material rolled through a mill stand, where a position regulator receives a screwdown reference signal and a signal representing the actual screwdown position and responds thereto to adjust the rolling force until the error between the reference signal and the position signal is substantially zero, a gauge deviation correction control comprising: first means for measuring the gauge deviation at a predetermined transport distance from the rolling stand; second means operative each time after said position regulator has produced a substantially zero error signal and after the strip element then has moved through said predetermined transport distance to said second means for producing a mill spring constant correction signal proportional to the average summation of gauge deviation divided by roll force change.
Claim 11
Dependent Claim
49 words
The gauge deviation correction control of claim 8 wherein said position regulator is controlled by a reference signal produced as a function of initial screwdown position, average XRAY deviation exceeding a predetermined limit and the product of the last set of mill spring constant times change in roll force.
Claim 12
Dependent Claim
26 words
The gauge deviation correction control defined in claim 9 wherein said reference signal is defined by the function REF SO + XAVG + KM(FA - FO).
Claim 13
Dependent Claim
40 words
The correction control of claim 10 wherein each change signal is defined as DKM XO/DF where XO represents gauge deviation remaining after zero error regulation and DF is the change of rolling force which occurred during the zero regulation cycle.
Claim 14
Dependent Claim
31 words
The gauge deviation control of claim 11 wherein said second means produced an average correction signal DKMAVG SUMDKM/N where SUMDKM represents the summation of a series of N change signals DKM.
Claim 15
Dependent Claim
118 words
In combination: a screwdown position regulator responsive to a reference signal and a screwdown position signal for adjusting the rolling force until the error between the reference signal and the position signal is substantially zero; deviation limit testing and averaging means for producing a gauge deviation signal representing average gauge exceeding predetermined limits; a mill spring averaging processor for producing an averaged mill spring correction signal as a function of a number of gauge deviations remaining after the operation of said position regulator and as an inverse function of the corresponding rolling force changes occurring therein; and a screwdown reference signal processor for periodically updating the reference signal as a function of said averaged mill spring correction signal.
Claim 16
Dependent Claim
118 words
In combination: a screwdown position regulator responsive to a reference signal and a screwdown position signal for adjusting the rolling force until the error between the reference signal and the position signal is substantially zero; deviation limit testing and averaging means for producing a gauge deviation signal representing average gauge exceeding predetermined limits; a mill spring averaging processor for producing an averaged mill spring correction signal as a function of a number of gauge deviations remaining after the operation of said position regulator and as an inverse function of the corresponding rolling force changes occurring therein; and a screwdown reference signal processor for periodically updating the reference signal as a function of said averaged mill spring correction signal.
Claim 17
Dependent Claim
38 words
The combination of claim 13 wherein a transport distance processor is included for precisely determining when an element of rolled strip corresponding to zero regulation error has moved from the rolling position to the position of deviation measurement.
Claim 18
Dependent Claim
43 words
The combination of claim 13 wherein a sequence control is provided to cause operation of said deviation limit test and averaging such that two successive deviations must be detected to exceed a predetermined limit before the next regulation control is caused to begin.
Claim 19
Dependent Claim
15 words
The combination of claim 15 wherein said predetermined limits are + and - 1 percent.
Claim 20
Dependent Claim
27 words
The combination of claim 13 wherein said screwdown reference signal processor produces said reference signal according to the function REF SO + XAVG + KM(FA - FO).
Claim 21
Dependent Claim
34 words
The combination of claim 13 wherein said mill spring averaging processor produces said averaged correction signal as the function DKMAVG SUMDKM/N where SUMDKM represents the summation of a series of N mill spring changes.
References Cited (Backward Citations)
US3253438A
Cited
US3625037A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-10 | 1977-06-11 | 1977-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-10 | 1981-06-11 | 1981-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-10 | 1985-06-11 | 1985-12-11 | $7700.00 | Window Closed / Lapsed |