| 摘要 |
PURPOSE:To make a carriage run stably, by coupling a screw pulley to an output shaft of a speed reducer freely slidably in the axial direction and also so as to be fitted into the rotational direction, winding a wire around the screw pulley, and making tension of the wire constant. CONSTITUTION:A wire 3 is led to the outside of a wound part 8 of a screw pulley 7, and its end part on the left from a carriage 1 loaded with a read and store head is stretched to a wire guide large pulley 10. The screw pulley 7 is constituted so that a rotation of a motor shaft 52 is transferred to the screw pulley 7 when a motor 5 is rotated. When a difference between a large pulley 101 and a small pulley 102 is made equal to length of the wire wound part 8 and the pulley 7 is made freely movable in the axial direction against the motor shaft 52, a wire of the carriage 1 side and a wire of the pulley 7 side are held in parallel with each other. |
