| 摘要 |
PURPOSE:To reduce electric power consumption, by lighting the exposure light source just before the exposure light source is positioned to the end part of manuscripts, and turning off the exposure light source just after the light source completed the exposure of image lights of manuscripts. CONSTITUTION:This electronic copying machine has a mechanism in which a power source lighting circuit 6a is closed when a pulse signal is generated and an exposure light source 6 is turned on. Then, a central controlling circuit 48 gives the output to the electric current supplying circuit of an electricity charging device 19 and operates the electricity charging device 19 after a time ts which is equal to a period from a time point where a manuscript 2 is detected by a manuscript size sensor 10 to another time point where exposure to the manuscript 2 is started by the exposure light source 6, is passed from a time point where the pulse signal of a signal converting circuit 45 is generated. Then, the central controlling circuit 48 stops the working of the electricity charging device 19, etc., and turns off the exposure light source 6 after an appropriate time passed. In this way, the exposure light source is turned on only for necessary time and, therefore, its electric power consumption can be reduced. |
