| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a developing device, wherein a successful image is stably obtained over a long period by detecting retention of developer and clogging of a foaming cell of a developer supply member around the developer supply member to return the developing device to a normal state even when the retention and the clogging are about to happen or happen. <P>SOLUTION: The developing device 100 comprised of a developer carrier 106, a regulation member 102 and the supply member 105 and which performs development by impressing bias to the developer carrier 106, is constituted so that a means for measuring minute current flowing to a nip part where the developer carrier 106 contacts with the developer supply member 105 is included, and predetermined bias is impressed between the developer carrier 106 and the developer supply member 105 when drive is stopped, and when a value of the minute current to be measured when reaching a certain threshold or more, the developer supply member 105 is driven so as to be rotated at least one rotation or more at normal rotation speed or faster for a fixed time before the next image formation. <P>COPYRIGHT: (C)2007,JPO&INPIT |
