| 摘要 |
PROBLEM TO BE SOLVED: To provide a reduced-size development device with an image quality deterioration suppressed.SOLUTION: A development device includes: a developer retainer (R0y) that includes a rotary member (12) rotating around an outer circumference of a magnetic member (11); and a transport member (16), with its half or more disposed within a projection range (A1) of the developer retainer (R0y), for transporting a developer contained in a developer housing (V) while agitating the developer. Further, an attraction magnetic pole (S3) is disposed upstream of a virtual line segment (L0) in a rotational direction of the rotary member (12), the line segment connecting a rotary center of the rotary member (12) to that of the transport member (16). Magnetic force of a separation magnetic pole (S2) is set between 35 mT and 45 mT, both ends inclusive, while that of the attraction magnetic pole (S3) is set between 38 mT and 54 mT, both ends inclusive. An angle formed by the separation magnetic pole (S2) and attraction magnetic pole (S3) is set between 98 and 117 degrees, both ends inclusive, in relation to the rotational center of the rotary member (12). |
