| 摘要 |
PROBLEM TO BE SOLVED: To suppress clogging of toner accompanying supply of toner into a developing unit.SOLUTION: A developing device acquires temperature information obtained by measuring or estimating an environmental temperature of a developing unit and printing rate information representing the area ratio of an area to which a toner of an electrostatic latent image formed on an image carrier is adhered; and when continuation of a predetermined high-temperature and continuation of a predetermined low-printing rate are determined on the basis of the temperature information and printing rate information, makes a transition to a moderate supply mode where the amount of supply of a toner from a toner cartridge to a developer per unit time by a supply member supplying the toner inside the toner cartridge to the developing unit is relatively reduced.SELECTED DRAWING: Figure 5 |
