| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device equipped with a developing device where next image formation is not affected adversely by the high consumption of developer by detecting the consumed developer immediately even when much developer is consumed by the image formation. SOLUTION: By providing a sensor (18) for detecting the quantity of the developer or the concentration of the developer near the 2nd aperture (13) of a partitioning member (11) by which the flow of the developer is turned back toward a 2nd carrying means (10) located at a position separate from a developing roller (2) or a supply roller (3) while putting the member (11) in between from a 1st carrying means (9) carried along from one end to the other end of the roller (2) or the roller (3), quantity of the consumed developer is detected in a short time and the next image forming operation is stopped based on the detection signal. |
