Patent ID: 9488931
Filing Date: 2016-11-08
CPC Classification: G03G

Claim Text:
1. An image forming apparatus comprising: at least one latent image bearer; at least one developing device to contain developer including toner and carrier, each of the at least one developing device including: a toner supply device to supply the toner to the at least one developing device; a transfer device to transfer the toner image onto a recording medium; a controller to cause, based on a detected toner concentration detected by the toner concentration detector, the toner supply device to keep the concentration of toner in the developer in the at least one developing device at a target toner concentration during image formation, wherein the controller executes forced toner consumption in which the at least one developing device supplies the toner to the at least one latent image bearer to forcibly consume the toner at a predetermined forced toner consumption timing, the controller starts the forced toner consumption while inhibiting the toner supply device from supplying the toner and completes the forced toner consumption when the detected toner concentration falls to a prescribed toner concentration lower than the target toner concentration, and subsequent to the forced toner consumption, the controller executes a post-consumption toner supply operation in which the toner supply device supplies toner to the at least one developing device; and a memory device to store consumption ongoing data indicating that the forced toner consumption is ongoing, wherein the controller stores the consumption ongoing data in the memory device at the predetermined forced toner consumption timing, when the forced toner consumption completes, the controller deletes the consumption ongoing data from the memory device, and when either the forced toner consumption or the post-consumption toner supply operation is interrupted while the memory device stores the consumption ongoing data, the controller executes the forced toner consumption and the post-consumption toner supply operation before starting image formation.