| 摘要 |
PURPOSE:To detect the residual amts. of toners in respective axial positions and to improve the reliability of the detection by providing a toner sensor movably in the axial direction of a photosensitive body within a toner container. CONSTITUTION:A moving window 45 parallel with the axial direction of the photosensitive drum is bored on the rear surface of the toner container 44 in a developing section and the toner sensor 38 is mounted on the inner side thereof. A moving knob 46 mounted to the sensor 38 is exposed to the outside of a window 45. The sensor 38 moves in the axial direction of the photosensitive drum when this knob is moved laterally. Position detecting sensors 48a, 48b, 48c are mounted near both right and left ends and central part of the window 45. The position at the top end of toners does not uniformly fall when the residual amt. of the toners decreases on increasing of the number of printed sheets and, therefore, the knob 46 is moved to the positions of the sensors 48a to 48c and the lighting condition of a toner absence lamp is investigated. Judgment is made that the toners remain unequally when the lamp is lighted or put out. Oscillation is then applied to be container 44 from the outside to uniformly distribute the toners. The toners are replenished when the number of lighting times of the lamp 47 increases. The residual amt. of the toners in the container 44 is detected in this way. |
