JPS5758164A - Synchronous control system of copying machine - Google Patents

Abstract

PURPOSE:To speed up copying operation by stortening a stand-by time by providing an exposure-start-readiness sensor, which detects the passage of transfer paper, at the position equivalent to the distance from the exposure position of a photosensitive drum to a resist position, on a carriage path for the transfer paper. CONSTITUTION:On a carriage path for transfer paper 2, an exposure-start-readiness sensor 20 which detects the passage of the transfer paper 2 is provided at a position D equivalent to the distance from the exposure positin C of a photosnsitive drum 10 to a resist positin A and in front of the position E of a resist roller 5, a resist sensor 21 is also provided; and the output ES of the sensor 20 is passed through an amplifier 30 and a differentiating circuit 31 to obtain an exposure start signal ESA, which is sent to an exposrue part to perform exposure. Simultaneously, an optical picture signal PS is inputted to a timer 33 through a differentiating circuit 32 on the basis of the detection signal ES of the exposure, and the output RS of the resist sensor 21 is inputted to a timer 35 through a differentiating circuit 34 to perform timer operation.