| 摘要 |
PROBLEM TO BE SOLVED: To obtain a method and a device to control toner density for an electronicphotographying image generating system in which image density fluctuation caused by the fluctuation of toner concentration is appropriately compensated for by utilizing a software modeling. SOLUTION: A time delay model of the behavior of a developer housing is maintained as mechanical software of a controller which approximates the delay between the toner concentration detection and the image developing, the delay caused by toner carrier mixing and the delay caused by the carrying of the toner carrier to a developing roll from the developing housing. These approximations are adjusted based on the actually measured values of the operations over very recent few minutes. A controller 132 compares the sensor signals representing toner concentration predicting values with the sensor signals representing an average of toner concentration measured values and detects a long term drift and a short term drift. The controller computes and transmits feedforward correction signals based on the approximations and the detected drifts to compensate for the fluctuation of the toner and adjusts the electrostatic set point of an electrostatic controller 144 for every printing paper. |
