| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device constituted in such a way that an image with excellent quality can be always formed without lowering image density even with respect to such printing that an image area ratio is high by always keeping toner concentration in a developing device constant. SOLUTION: This device is provided with a toner supply control means. The toner supply control means is constituted so that a toner supply device is controlled based on the detected value of a reference image density detection means 5 when the number of continuous image forming sheets is under the prescribed number of sheets and controlled based on a compared result between the detected value of a toner density detection means 14 and the target value of the toner density when the number of continuous image forming sheets is equal to or over the prescribed number of sheets. In the case that the detected value of the detection means 14 is detected to be lower than the target value of the toner density when toner is controlled to be supplied based on the detected value of the detection means 5, the toner is controlled to be supplied according to the detected value of the detection means 14. |
