Image forming apparatus having developing device with magnet roller with particular magnetic flux density
US6671484B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 5, 2001 |
| Grant date | Dec 30, 2003 |
| Priority date | — |
| Expiry date | Oct 11, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G2215/0177
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An image forming apparatus of the present invention includes a developing device of the type causing a developer to form a magnet brush on the surface of a developer carrier having a magnet roller in a developing region or nip for development. The magnet brush contacts and thereby develops a latent image formed on an image carrier. The magnet roller has a main magnetic pole for development wherein the flux density in the tangential direction has a maximum variation ratio of 40 T/m or above in absolute value. The apparatus of the present invention increases image density and faithfully reproduces even low-contrast images with a low-cost configuration. Further, the apparatus reduces image defects, including granularity and the omission of the trailing edge of an image, even if the range over which the magnet brush and image carrier contact is reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.