| 摘要 |
PROBLEM TO BE SOLVED: To narrow the range of quantitative change of toner in a developing device due to toner consumption and, therefore, enable satisfactory image formation and to prevent toner deterioration and, therefore, restrict change in image quality with time, by providing a developing part and a toner storage part separately and adding a necessary quantity of toner into the developing part from the toner storage part as necessary based on the result of detection by a toner quantitative detection means. SOLUTION: A developing part 9 and a toner storage part 6 for storing one-component developer used for development are accommodated in a housing by being formed as units and are disposed independently of each other. When a developing operation is carried out, a quantity of toner in a toner pool is detected by a toner quantitative detection means 5 set on the side of a toner intake port. When the quantity of toner is small from the result of the detection, the toner is properly supplied from the toner storage part 6 and the quantity of toner in the developing part 9 is restricted. Thus, even in a developing device in which an image carrier and a toner carrier are abutted against each other by means of a spring, the abutted state is maintained and steady satisfactory image formation can be performed. |
