| 摘要 |
PURPOSE:To raise properly a scanning speed for redunction copy without reducing the copy speed for unmagnification copy and magnification copy by providing a means which changes the length of auxiliary run in accordance with a set power. CONSTITUTION:A CPU 18 gives instructions to an input/output control part 21 through an address and data bus 20 in accordance with a program stored in an ROM 19 and gives a turn-on/off signal 23 and forward/backward movement signal 24 to a motor 22 which moves, namely, scans an optical system such as a lamp 4 or the like. The CPU 18 gives commands to a counter 25 to change the frequency of a clock signal 26, which is inputted to the counter 25, in accordance with various powers of a copying machine and gives clock pulses having a prescribed frequency to the motor 22 through a line 27, and the frequency of pulses for reduction copy is higher than that for unmagnification copy and is lower for magnification copy. Since the moving speed, namely, the scanning speed of the optical system is changed in accordance with powers in this manner, the time required for the rise of the motor 22 to a certain speed is changed in accordance with powers. |
