| 摘要 |
PURPOSE:To drive an image reader with less speed variance by adding an external additional element like a mechanical damper to the scanner only in a specific area of the speed range corresponding to a read magnification and disconnecting the external additional element in the other speed area. CONSTITUTION:When the output of a speed setter 75 rises, a drive circuit 76 turns on or off a clutch 23 in accordance with the set speed of a speed set signal supplied from the speed setter 75. When the moving speed of an optical system is low, a mechanical damper 24 is connected to a stepping motor 12 to increase the moment of load inertia of the optical system, namely, the stepping motor 12, and the optical system is smoothly driven to considerably reduce the peak of a high frequency component. When the moving speed of the optical system is high, the mechanical damper 24 can reduce the moment of load inertia of the stepping motor 12, and a bad influence upon the rise characteristic is prevented. |
