| 摘要 |
PURPOSE:To shorten a selecting time of reducing magnification by constituting so that an optical system is not brought to a position control when the reducing magnification is being changed, and when the reducing magnification is selected finally, the optical system is brought to the position control in accordance with it. CONSTITUTION:In a copying machine which is capable of selecting many kinds of reducing magnifications, for instance, in case when the reducing magnification is changed to 140% from 100%, when a push-button 5 is pushed continuously, a timer 31 and 33 start, also a differentiating circuit shifts a shift register by outputting a positive signal, and display of a display part 6 is changed to 120% from 100%. When a constant interval of time elapses, if on of the push-button 5 is continued, the timer 31 is operated and the timer 33 is reset and starts again. Subsequently, the display part 6 displays 140%. In this case, when the push-button is turned off, the timer 31 suspends its operation, but the timer 33 continues its operation, count-up is executed after a constant interval of time elapses, and a signal of operating an optical system moving motor is outputted. |
