| 摘要 |
PROBLEM TO BE SOLVED: To classify residual toner amounts into plural stages and to precisely discriminate the residual toner amounts. SOLUTION: A toner sensor 21 detects a change in permeability changed by the rotation of an agitator 37 stirring magnetic toner. A permeability change pattern is previously stored for various residual toner amounts and the pattern of the detected change in the permeability is collated with the stored pattern, to classify the residual toner amounts into the plural stages and recognize the residual toner amounts. Since the pattern of the change in the permeability by the rotation of the agitator 37 is different according to the residual toner amount, it can be discriminated by the collation of the pattern. Further, the residual amount is discriminated by the permeability actually measured by the sensor, so that detecting accuracy is made high. |
