| 摘要 |
PURPOSE:To perform invariably stable transfer by detecting the resistance value of recording paper fed prior to transfer, and then automatically controlling the amount of corona discharge by a corona discharger for transfer to the best value according to the detected resistance value. CONSTITUTION:The potential at a point (a) which corresponds to the resistance value (including the constant resistance value of a resist roller in this case) of recording paper 10 detected in a voltage drop method is classified into (n) stages through the comparison of a window comparator 19 composed of comparators CMP1-CMPn wherein (n) stages of reference voltages Vref1-Vrefn are set respectively, and a driver 20 is driven by the combination of high-level outputs of the comparators CMP1-CMPm (m=1-n) which corresponds to the classified potential at the point (a), thus adequately exercising control over the corona current or grid voltage of a corona discharger for transfer or control for varying its opening area or discharge distance. |
