| 摘要 |
PURPOSE:To accurately detect toner concn. by providing a toner concn. detecting means at the bottom part of a developing casing in an area formed with plural stirring/mixing/carrying means and a dash-board between the means. CONSTITUTION:A developing brush roll 6 is arranged rotatably freely at the developing casing 1. Stirring/mixing/carrying rollers 4, 3a are provided extensively so as to be driven rotatably in parallel with the roll 6 keeping a constant interval (d) at the rearward of the roll, and a developer housed in the casing 1 is stirred and mixed. A part between those carrying rollers 4, 3a is partitioned with the dashboard 5 of short length being extended in parallel between the rollers. And the toner concn. detecting part 2a is provided at the bottom part of the casing 1 in the area enclosed with the rollers 4, 3a, and the dashboard 5. Thereby, since no influence of a magnetic force of a magnetic field is applied, the detecting part 2a can accurately detect the toner concn. Also, a toner refilling part is provided at position neighboring to the roll 6, which supplies toner to the roll 6. |
