| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device with which the quantity of recycling toner can precisely be grasped, the reliable transportation of recovered toner can be performed, and the service life of a screw pump can be prolonged. SOLUTION: The image forming device which adopts a electrophotography method and is provided with a toner recycling mechanism (a gas flow transport means 4, a gas feeding means 5) for recovering toner remaining on a photoreceptor after passing through a transfer step, returning the recovered toner to a developing means as a gaseous mixture with a gas flow, and reusing the mixture, is provided with a transfer means 2 for transferring a toner image formed on the photoreceptor to a body to be transferred (transfer paper, transfer belt or the like), a reflection type optical density sensor for detecting the optical density of toner image pattern formed on an image carrier before and after transferring the toner image pattern on the body to be transferred, respectively, and a control part for calculating a toner transfer rate on the basis of the optical density before and after transferring the toner image pattern detected by the reflection type optical density sensor to the body to be transferred, and using the toner transfer rate as a controlling factor of the toner recycling mechanism. |
