| 摘要 |
PROBLEM TO BE SOLVED: To provide a speed controller for a straightening machine by which deformation in the axial direction of a rolled stock is prevented. SOLUTION: At the time of control the current of a straightening roll driving motor according to a load torque current reference IR calculated based on a speed reference NR, by calculating acceleration and deceleration torque current IA based on the detected value of speed of the straightening roll driving motor and subtracting the calculated acceleration and deceleration torque current IA from the load torque current reference, a load torque current ILO is determined and expressed in terms of a load torque GLO. Further, this load torque GLO is compared with a preset reference value GS and, when the load torque GLO is over the reference value GS, the load torque current reference IR at this point of time is stored and held, and the magnitude of the load torque current reference IR hereafter is limited by the storing held value. In this way, the load torque of the straightening roll driving motor is always suppressed to the reference value or less. |
