| 摘要 |
PURPOSE:To appropriately evade an excessive state of a toner replenishment and to surely prevent ground contamination and toner scattering by maximizing the toner replenishment rate and setting a reference pattern detection mode shorter than usual, when an output of an image density sensor exceeds a control reference value. CONSTITUTION:After a main switch of an image forming device is turned ON, a reference pattern detection mode is executed once each per an exposure of 10 times, and a toner replenishment control by an image density sensor is executed. In such a case, when a sensor output VSP exceeds a second control reference value K2, it is under the toner concentration which can obtain correct density, therefore, the replenishing operation is executed by raising the toner replenishment rate to a state corresponding to 60% the maximum black solid part area rate. In such a case, after the toner replenishing operation is executed five times, the next reference pattern detection mode is executed, and the detection interval is shortened. In such a way, an excessive state of the toner replenishment is evaded appropriately, and ground contamination and toner scattering can be prevented surely. |
