| 摘要 |
<p>The present invention effectively reduces the influence of backlash and enables precise position control even when a drive mechanism uses rotary drive of gears. Therefore, in moving a subject to be moved by rotation of the gears, an original point for position control is positioned by a sensor flag before the position is controlled. At the time of this positioning, bias means so generates bias in the direction of movement of the subject to be moved that backlash of gear drive is removed. This sets the backlash to substantial "zero" in positioning of the original point and stabilizes an original point reset position.</p> |
