PURPOSE: To adequately perform copying of various magnifications with the simple apparatus by controlling the electromagnetic joint between an original-scanning motor and a pulley by the use of memory circuits, logic circuit etc.

CONSTITUTION: A counter circuit 22, 1/10 divider 24 and amplifier 25 are provided between a crystal oscillator 21 and an aperture-card-support-table-driving synchronous motor 4, and counter circuits 26, 30, 32, dividers 27, 31, timing circuit 28, memory circuits 29, 33, logic circuit 34 and output circuits 35 are provided between the crystal oscillator 21 and electromagnetic joint 5. As a result of this, the synchronous motor 4 is driven by the signal from the crystal oscillator 21, and the memory circuit 33 which has been written with the original picture scanning start timings and original scanning end timings suited for copying paper of various sizes and the copying paper sizes receives the pulses which the counter circuit 32 generates when the drum of a photosensitive plate passes the reference position during copying cycle and counts and is inputted with the input pulses from the counter circuit 30. The output circuit 35 drives the joint 5 to revolve the pulley 6 at the timing suited for the copying paper of the specified size.