METHOD AND APPARATUS FOR FORMATION OF TONER PATTERN AS WELL AS TONER REPLENISHMENT DEVICE

摘要

PROBLEM TO BE SOLVED: To perform a developing ability control which enables the widening of the range of effectivity (At ) of a toner material when it is charged on a usable prescribed carrier. SOLUTION: This toner pattern forming method comprises a step of temporarily stopping the toner supply until the toner density is reduced to predetermined quantity; a step of sensing a test patch on a charge holding surface and generating a signal for showing the toner density; a step of determining the inclination of run-down by use of the signal and the predetermined quantity; a step of comparing the inclination of run-down with a target value; and a step of increasing or reducing the toner supplying ratio according to whether the inclination of run-down is larger than the target value or smaller than it.