| 摘要 |
<p>PURPOSE:To reduce the load of a driving means and to facilitate structure by transmitting driving force to a sensor roller only when an original is inserted between the sensor roller and a read means. CONSTITUTION:A first optical detector 58 detects the original 62, drives a motor 60 and transmits driving force to the sensor roller 55. Since the roller 55 is brought into contact with a direct read sensor 54 at that time and friction resistance exists, the meshing of a torque limiter 1 is slipped 86 only a gear 61 runs idle and the roller 55 does not rotate. When the tip of the original 62 reaches the read position of the sensor 54, reading is started. When the original 62 is fed and it reaches a place between the roller 55 and the sensor 54, friction resistance added to the roller 55 becomes small, torque added to the limitter 1 is reduced, they are meshed, torque is transmitted and the roller 55 rotates. The load of the motor 60 becomes friction resistance between the original 62 and the sensor 54, and it does not become the overload of the motor 60. Since a clutch is automatically switched by the load of the limitter 1, structure can be simplified.</p> |
