| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a development device capable of suppressing fluctuation in density of an image formed on an image carrier body when changing a peak-to-peak voltage value of a pulse voltage; and to provide a process cartridge and an image forming apparatus having the development device. <P>SOLUTION: A first power supply 31 is for crowd pulse output, and primary and secondary sides of a power supply circuit are separation types, namely, the secondary side being floating with respect to GND. A second power supply 32 is for a minus DC bias and the primary and secondary sides have a configuration to be connected to a common GND. Pulse voltage application means includes a pulse output generating circuit 37 as a pulse voltage generating circuit which comprises an A-phase pulse generating circuit 33 generating an A-phase pulse and a B-phase pulse generating circuit 34 generating a B-phase pulse. A crowd pulse control circuit 67, or control means, changes the output level of the first power supply 31 based on the detection result of a humidity sensor 40, or humidity detecting means, to adjust the peak-to-peak voltage value. <P>COPYRIGHT: (C)2012,JPO&INPIT |
