| 摘要 |
PURPOSE:To prevent step-out of a pulse motor due to mechanical loosening of components during line feed of a medium, by rotating a motor forward with a larger rotary angle theta2 than a rotary angle theta1 corresponding to the feeding amount of the medium then rotating the motor rearward by a differential rotary angle such that the rotary angle of the motor will be Q1. CONSTITUTION:At fist, a pulse motor is rotated by an angle theta2. During rotation, a load torque T1 is produced through friction during traveling of a medium irrespective of the rotary angle of the pulse motor. Consequently, when the pulse motor is stopped, a torque tm1 caused by the recovery force is applied in the opposite direction from the rotary direction of the pulse motor. Since the pulse motor is rotating excessively by the amount of (theta2-theta1), if the pulse motor is rotated reversely by an angle (theta2-theta1) its rotation is promoted by the recovery force so as to stop the pulse motor with the rotary angle of exactly theta1. Consequently, the rotary angle is changed from thetam1 to (thetam1-theta2) by the recovery force so as to reduce the torque caused by the recovery force from Tm1 to Tm2. Consequently, step-out of motor can be prevented. |
