Patent ID: 8528364

Claim:
A method of making a glass ribbon comprising: producing a glass ribbon in a down draw glass making process, the glass ribbon comprising a visco-elastic region; contacting the visco-elastic region of the glass ribbon with opposing rollers, the opposing rollers applying a pinch force in a thickness direction of the glass ribbon and a tension force in an across-the-ribbon direction of the glass ribbon; measuring a magnitude of the pinch force in the thickness direction of the glass ribbon or a magnitude of the tension force in the across-the-ribbon direction of the glass ribbon and producing a force signal representative of the measured magnitude of the pinch force or the tension force; comparing the force signal with a set point, and producing a corrective signal representative of a difference between the force signal and the set point; and using the corrective signal to drive an actuator that actively repositions at least one of the opposing rollers relative to the glass ribbon to vary the pinch force or the tension force applied to the glass ribbon by the opposing rollers so that the applied pinch force or tension force is substantially equal to the set point.