| 摘要 |
PURPOSE:To make horizontal magnifications equal to vertical magnifications to prevent the distortion of a picture, by using an independent driving motor for driving and correct the speed of an original platen driving motor from a preliminarily determined proper value. CONSTITUTION:When magnifications are selected, a variable clock generator 151 generates a clock signal 162 corresponding to them. A rotation speed signal 163 having a frequency proportional to the rotation speed of the original platen driving motor 9 is supplied to a phase comparator 152 and is compared with the clock signal 162. The motor 9 is a DC motor, and its rotation speed is controlled in accordance with the pulse width of a motor driving pulse signal 167, and frequencies of the clock signal 162 and the rotation speed signal 163 are made coincident with each other. Thus, the rotation speed is controlled to a desired rotation speed, and an original platen 2 is moved in a desired speed corresponding to copy magnifications. |
