| 摘要 |
<P>PROBLEM TO BE SOLVED: To minimize the need for external circuits even when PWM drive is performed as a countermeasure to the excessive temperature rise caused when electromagnetic equipment, such as the electromagnetic clutch, electromagnetic solenoid, etc., is energized for a long time and, at the same time, to obtain the initial torque required by the electromagnetic equipment, eliminate the need of a fan, and suppress noise to a lower level when the equipment is energized. <P>SOLUTION: When the CPU 1 of the main body of an image forming device sets energization and the electromagnet equipment, such as the electromagnetic clutch 31, electromagnetic solenoid 32, etc., receives an energization starting instruction, continuous 'on' signals are supplied to the transistors 21 and 22 of a driving circuit by operating a first drive control means by the period of first set time set by means of a control circuit 10. After the first set time ends, PWM signals are immediately supplied to the transistors 21 and 22 by operating a second drive control means at a second set time ratio set by means of the control circuit 10. When an energization terminating instruction is issued from the CPU 1 thereafter, the energization is stopped by stopping the second drive control means. <P>COPYRIGHT: (C)2003,JPO |
