| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device capable of accurately detecting the residual amount of developer in a developing device by appropriately relating output from a developer residual amount detecting means to the residual amount of the developer and capable of informing a user of appropriate cartridge exchanging time (purchasing time) by informing the user of the detected result, and to provide a cartridge attached to/detached from the image forming device and an image forming system. SOLUTION: In this image forming device, the cartridge B having a developer storing part 4, the developer residual amount detecting means 30 capable of successively outputting a signal in accordance with the amount of the developer in the storing part 4, and a storage means 20 can be attached to/detached from a device main body 100. Information corresponding to the output from the detecting means 30 in a state where the storing part 4 is not filled with the developer is stored in the storage means 20. |
