| 摘要 |
<P>PROBLEM TO BE SOLVED: To simplify the structure of an apparatus and to reduce the size and cost of the apparatus by performing a plurality of detections with respect to a plurality of developing devices and toner vessels of a development unit using one optical detector. <P>SOLUTION: A plurality of detecting sections KS1-KS4, YS1-YS4, MS1-MS4, CS1-CS4 for performing at least two detections among detection of attachment of each toner cartridge 21, detection of the toner end of each toner cartridge 21, detection of attachment of each developing device 8 to a prescribed home position and detection of replacement timing of each developing device 8 are arranged at different positions on a development unit 7 along a passage trajectory which passes the detecting position of a photo-interrupter 22 by driving of the development unit 7. <P>COPYRIGHT: (C)2004,JPO |
