| 摘要 |
PROBLEM TO BE SOLVED: To improve performances of a developing device with sufficient balance in terms of fog, black solid uniformity, ghost, hair line uniformity and image edge failure. SOLUTION: A developer quantity regulating means 60c includes: a contact part that is brought into contact with a developer carrier in a direction counter to the direction of the rotation of the developer carrier; a step part formed on the contact part in the direction of separation from the developer carrier 60b2; and a separate part disposed upstream from the step part in the direction of the rotation of the developer carrier. The separate part of the developer quantity regulating means is located in the vicinity of one of the magnetic poles of a fixed magnetic field generating means 60a, and the separation part includes the position satisfying the condition expressed by ¾Br¾/¾B¾≥0.5 established for the density B of a magnetic flux generated at least by the magnetic pole. ¾B¾ represents the magnitude (¾B¾=¾Br<SP>2</SP>+Bθ<SP>2</SP>¾<SP>1/2</SP>) of magnetic flux density B. Br and Bθrepresent the vertical component and horizontal component respectively of the density B of the magnetic flux, formed on the surface of the developer carrier, relative to the surface of the developer carrier. COPYRIGHT: (C)2007,JPO&INPIT |
