| 摘要 |
PURPOSE:To eliminate the fluctuations in line tension during shearing by detecting the main circuit current of the motor for a driving roll, and flowing the current corrsponding to the line tension operated value during shearing operation of a shear as compensating current to the main circuit. CONSTITUTION:A tension operation device 37 stores momentary tension values with the main circuit current I1 driving a bridle roll 18 and the main circuit current I2 of the motor on the take-up side selected with a coiler selector 38 and converted to the value on the bridle roll 18 side as a synthesized value. On the other hand, blade position detector 34 determines the cutting angle of the blade position of a shear 19 from a prescribed equation. The pulse signal from a pulse oscillator 24 are measured, and shearing timings are detected. A compensating current applying device 36 applies the storage value of the operation device 37 to the current control system 30 of the roll 18 at the shearing timing signal, thereby compensating the fluctuations in the tension on the upper stream side than the roll 18. |
