| 摘要 |
PROBLEM TO BE SOLVED: To accurately detect information by being hardly affected from soiling by a developer and toner in the case of detecting the state information of an attaching member attachable/detachable. SOLUTION: A hard copying device is provided with a primary side coil 28 and a primary side core 29. A developing cartridge 23 is provided with a secondary side coil 30 and a secondary side core 31. Relating to the secondary side coil 30 and the secondary side core 31, magnetic induction (mutual induction) is generated between the primary side coil 28 and the primary side core 29 provided on the side of the hard copying device, so that the information on an attaching state is detected from a frequency characteristic by the hard copy device. |
