Rolling mill including gauge control

Claim 2

The combination of: a. a rolling mill, including a pair of roller elements operative with a moving product for reducing the thickness of said product; b. control means operative with at least one of said roller elements, in response to a control signal, for controlling the spacing between said roller elements; and c. a system for producing a first signal, which is generally indicative of the variation between a preselected value corresponding to the desired spacing between said roller elements and the actual spacing therebetween, and which includes a fundamental component which varies cyclically with the rotation of said elements, said system including tunable electrical means for acting on said first signal and producing a component signal corresponding to said fundamental component, and means for combining said first signal and said component signal and for producing an output signal free of said component for said control means.

Claim 3

means for producing a second signal, indicative of but in inverted polarity of said component; and

Claim 4

means for producing a second signal, indicative of but in inverted polarity of said component; and

Claim 5

In the combination of: a. a strip rolling mill, including a pair of roller elements operative with a moving strip for reducing the thickness of said strip; b. control means operative with at least one of said roller elements for controlling the spacing between said roller elements in response to a control signal; and c. a system for producing a control signal generally indicative of the variation between a preselected value, corresponding to the desired spacing between said roller elements and the actual spacing therebetween; the improvement wherein said system comprises:

Claim 6

In the combination of: a. a strip rolling mill, including a pair of roller elements operative with a moving strip for reducing the thickness of said strip; b. control means operative with at least one of said roller elements for controlling the spacing between said roller elements in response to a control signal; and c. a system for producing a control signal generally indicative of the variation between a preselected value, corresponding to the desired spacing between said roller elements and the actual spacing therebetween; the improvement wherein said system comprises:

Claim 7

means for summarizing said first and second signals to produce a control signal free of said component.

Claim 8

means for summarizing said first and second signals to produce a control signal free of said component.

Claim 9

In rolling mill apparatus, the combination comprising: a. a screwdown motor for selectively adjusting the spacing between the faces of a pair of work rolls of the mill; b. a drive motor for driving said work rolls; c. a tachometer device for producing a tachometer electrical signal indicative of the rotation frequency of said work rolls; d. a load cell device for sensing the load force between said work rolls and providing a load force electrical signal indicative of said force; e. a filter circuit for receiving said tachometer electrical signal and said load force electrical signal, and for selecting and inverting, as a function of said tachometer electrical signal, the component of said load force electrical signal which has a fundamental frequency corresponding to said rotation frequency and thereby provide an inverted component signal; f. first summarizing means, for receiving and summarizing a load force electrical signal from said load cell device and said inverted component signal, and for providing a summarized signal, which may be designated as a first summarized signal; g. set point circuit means for receiving said first summarized signal, comparing it with a selected value, and providing a differential signal which is indicative of the difference between said selected value and the value of said first summarized signal; h. means for providing a screwdown position signal indicative of the relative spacing between said faces of said work rolls; and i. second summarizing means, for receiving and summarizing said differential signal and said screwdown position signal, and providing a control signal for said screwdown motor in accordance with the roll spacing necessary to provide the desired thickness of the product being processed.

Claim 10

In rolling mill apparatus, the combination comprising: a. a screwdown motor for selectively adjusting the spacing between the faces of a pair of work rolls of the mill; b. a drive motor for driving said work rolls; c. a tachometer device for producing a tachometer electrical signal indicative of the rotation frequency of said work rolls; d. a load cell device for sensing the load force between said work rolls and providing a load force electrical signal indicative of said force; e. a filter circuit for receiving said tachometer electrical signal and said load force electrical signal, and for selecting and inverting, as a function of said tachometer electrical signal, the component of said load force electrical signal which has a fundamental frequency corresponding to said rotation frequency and thereby provide an inverted component signal; f. first summarizing means, for receiving and summarizing a load force electrical signal from said load cell device and said inverted component signal, and for providing a summarized signal, which may be designated as a first summarized signal; g. set point circuit means for receiving said first summarized signal, comparing it with a selected value, and providing a differential signal which is indicative of the difference between said selected value and the value of said first summarized signal; h. means for providing a screwdown position signal indicative of the relative spacing between said faces of said work rolls; and i. second summarizing means, for receiving and summarizing said differential signal and said screwdown position signal, and providing a control signal for said screwdown motor in accordance with the roll spacing necessary to provide the desired thickness of the product being processed.

Claim 11

Electrical control means, adapted for use in controlling the spacing between the work rolls of rolling mill apparatus, which includes a screwdown motor comprising: a. a filter circuit for receiving a first signal, indicative of the rotation frequency of the work rolls of a rolling mill, and a second signal, indicative of the spacing between said work rolls, said filter circuit including means for selecting and inverting a compoNent of said second signal, which component has a fundamental frequency corresponding to the frequency of said first signal; and b. means for summarizing said second signal and said inverted component and providing a summarized signal free of said component for controlling the operation of said screwdown motor.

Claim 12

Electrical control means, adapted for use in controlling the spacing between the work rolls of rolling mill apparatus, which includes a screwdown motor comprising: a. a filter circuit for receiving a first signal, indicative of the rotation frequency of the work rolls of a rolling mill, and a second signal, indicative of the spacing between said work rolls, said filter circuit including means for selecting and inverting a compoNent of said second signal, which component has a fundamental frequency corresponding to the frequency of said first signal; and b. means for summarizing said second signal and said inverted component and providing a summarized signal free of said component for controlling the operation of said screwdown motor.

Claim 15

A method as described in claim 5, which comprises the step of: imparting an initial condition signal, indicative of the force between the work rolls immediately after the work product is initially threaded therebetween, for minimizing oscillation of said second signal, which oscillation is due to step changes in said first signal.

Claim 16

The method as described in claim 5, wherein: said load force signal is a ramp-type signal and is tracked with an output signal in an electrical filter circuit.

Claim 17

The method as described in claim 7, wherein: said ramp-type signal is tracked with an error of less than 0.025 units after 0.75 T seconds, where T equals the period of said fundamental frequency.

Claim 18

Control means, adapted for use in controlling the operation of the work rolls of rolling mill apparatus, comprising: a. a tunable electric filter circuit for receiving a first signal, indicative of the rotation frequency of said work rolls, and a second signal, indicative of the load force between said rolls, said filter circuit including means for selecting a component of said signal, which component has a fundamental frequency corresponding to the frequency of said first signal and providing a third signal corresponding to said component; and b. summarizing means for receiving a signal corresponding to said second signal and for receiving said third signal, and providing a summarized signal, free of said fundamental component for controlling said operation.

Claim 19

Control means, adapted for use in controlling the operation of the work rolls of rolling mill apparatus, comprising: a. a tunable electric filter circuit for receiving a first signal, indicative of the rotation frequency of said work rolls, and a second signal, indicative of the load force between said rolls, said filter circuit including means for selecting a component of said signal, which component has a fundamental frequency corresponding to the frequency of said first signal and providing a third signal corresponding to said component; and b. summarizing means for receiving a signal corresponding to said second signal and for receiving said third signal, and providing a summarized signal, free of said fundamental component for controlling said operation.

Claim 20

Control means, adapted for use in controlling the spacing between the work rolls of rolling mill apparatus, comprising: a. load force means for sensing the load force between said rolls and providing a load force signal indicative of said force, which load force signal includes a component which has a fundamental frequency corresponding to the rotation frequency of said rolls; b. tunable electrical filter signal means for receiving said load force signal and providing a tuned filtered signal corresponding to said component; and c. means for simultaneously receiving said load force signal and said filter signal and for providing a summarized signal free of said component.

Claim 21

Control means, adapted for use in controlling the spacing between the work rolls of rolling mill apparatus, comprising: a. load force means for sensing the load force between said rolls and providing a load force signal indicative of said force, which load force signal includes a component which has a fundamental frequency corresponding to the rotation frequency of said rolls; b. tunable electrical filter signal means for receiving said load force signal and providing a tuned filtered signal corresponding to said component; and c. means for simultaneously receiving said load force signal and said filter signal and for providing a summarized signal free of said component.