| 摘要 |
PURPOSE:To keep the peripheral speed of pinch rolls lower than the speed of a steel strip for keeping a back tension constant and to improve the winding of the strip, by providing a strip tail-end detector to a final finishing stand as well as providing a back-tension controlling device and a speed controlling device to the pinch rolls. CONSTITUTION:A detector 30 detects the moment just before the tail end of a steep strip X runs out of a final finishing stand A, to output its signal (alpha) to a back tension controlling circuit 11 and speed controlling devices 20a, 20b. The devices 20a, 20b are provided to upper and lower pinch rolls 3a, 3b respectively and are constituted of speed regulators 21, 21, redctifiers 22, 22, rotary generators 23, 23, and an adder 24, respectively. A strip speed (a) and a slip set value (b) are previously inputted to the adder 24, which outputs them at the speed references. Further, a switch 240 is provided to the inputting side of slip setting. Accordingly, the output of the adder 24 is a strip speed when the output of the detector 30 is OFF. Further, the speed reference of the adder 24 is inputted to the regulator 21 and is compared with a feedback signal of a motor 4 of the generator 23 to output the result to the recitifier 22 as a control signal thereby rotating the motor 4 at the number of revolutions corresponding to the speed reference. |
