| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus employing a piezoelectric transformer type high-voltage power source apparatus capable of performing polarity changeover of an output voltage in a short time with a simple method. <P>SOLUTION: The piezoelectric transformer type high-voltage power source apparatus is provided with a positive output voltage generating circuit and a negative output voltage generating circuit. In this apparatus, the output voltage generating circuits each have a piezoelectric transformer; a piezoelectric transformer driving circuit; an output voltage detecting circuit; and a driving control circuit for outputting a control signal for controlling the piezoelectric transformer driving circuit on the basis of a signal from the output voltage detecting circuit, and an output voltage setting signal for setting an output voltage. The circuit has a time for simultaneously turning ON the positive and negative output voltage generating circuits in switching the output polarity of the piezoelectric transformer type high-voltage power source apparatus. <P>COPYRIGHT: (C)2007,JPO&INPIT |
