| 摘要 |
PURPOSE:To reduce the shift pitch of a head with high accuracy despite a large minimum step angle of a stepping motor, by combining the large and small pulleys. CONSTITUTION:A large pulley 13 is fixed to the rotary shaft of a drive pulley 9, and the both ends of a wire 10 are fixed at the outer circumferential part of the pulley 13 by means of screws 11. While a small pulley 12 is fixed to the rotary shaft of a stepping motor 5, and the middle part of the wire 10 is wound around the pulley 12 by >=1 turn and then fixed to the pulley 12 at a prescribed part to prevent the slip. The revolving center axes of both pulleys 12 and 13 are set approximately parallel to each other. Then the distance be tween both center axes is set at about (R1+R2+d), where R1, R2 and (d) show the radius of the pulley 12, the radius of the pulley 13 and the diameter of the wire 10 respectively. |
