Developing device for an image forming apparatus

Details Developing device for an image forming apparatus Developing device for an image forming apparatus

1995-04-28

1996-02-06

Pendegrass, Joan H.

Coating apparatus

With means to apply electrical and/or radiant energy to work...

With electromagnetic and/or electrostatic removal of...

355259, G03G 1508

Patent

active

054897475

ABSTRACT:
A developing device for an image forming apparatus and having a relatively hard first developing roller formed with fine N-S magnetic poles on the periphery thereof, and a relatively soft second developing roller for conveying toner electrostatically transferred thereto from the first roller toward a photoconductive drum. The toner is charged by friction while being passed through between the first roller and a blade, and then magnetically deposited on the first roller. At a position where the first and second rollers contact each other, only the adequately charged toner is electrostatically transferred from the first roller to the second roller. The second roller conveys the toner toward the drum. As a result, the toner is brought to a developing position in an amount corresponding to a saturation or maximum image density. The second roller is made up of a metallic conductive core, a semiconductive foam layer, and an insulative surface layer implemented by resin. The real resistance between the core and the surface is selected to be higher than 10.sup.3 .OMEGA. but lower than 10.sup.13 .OMEGA.. The ratio of the real resistance associated with the maximum temperature change to the real resistance at normal temperature is selected to be less than or equal to 4 in absolute value.

REFERENCES:
patent: 4537491 (1985-08-01), Komada et al.
patent: 5126799 (1992-06-01), Matsuura et al.
patent: 5212521 (1993-05-01), Ogawa et al.
patent: 5223668 (1993-06-01), Takaya et al.
patent: 5235387 (1993-08-01), Sato et al.
patent: 5287151 (1994-02-01), Sugiyama
patent: 5289241 (1994-02-01), Sugiyama et al.
patent: 5315357 (1994-05-01), Kamijo et al.

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