| 摘要 |
PURPOSE:To prevent the distortion of an image by inputting a pulse signal whose pulse occupation ratio is gradually made high for a prescribed time just after starting into the control circuit of an electromagnetic clutch and gradually increasing driving/transmitting force, when the electromagnetic clutch is started. CONSTITUTION:For instance, when the starting of a forward electromagnetic clutch 42 is started, the pulse signal whose pulse occupation ratio is gradually increased is inputted for the prescribed time just after the starting, and a current with respect to the clutch 42 is spuriously turned on/off, so that prescribed driving/transmitting force is completely turned on, after the prescribed time lapses. Thus, the turning on action at the time of the starting of the clutch 42 is gently and smoothly carried out. Even if a gap exits between a carriage supporting rod 27 and carriages 21 and 24, the carriages 21 and 24 are not rattled, so that the reading of an original is surely carried out, and the image without having the distortion can be formed. |
