Patent ID: 6198893
Filing Date: 2001-03-06
Classification: G03G

Abstract:
A plurality of developing units, wherein each of said developing units comprises:a case for accommodating toner;a developing roller rotatably supported by said case through a shaft;a supply roller rotatably supported by said case through a shaft and formed by an elastic member arranged to be pressed against said developing roller in such a manner as to supply toner to the surface of said developing roller; anda conveying fin rotatably supported by said case through a shaft in such a manner as to convey toner to the surface of said supply roller, whereinsaid developing roller, said supply roller, and said conveying fin are sequentially disposed in a horizontal direction, such that an angle .theta. made between a line connecting the center of rotation of said supply roller to the center of rotation of said conveying fin and a horizontal line is in a range from -20 degrees to +75 degrees with respect to said horizontal direction, wherein a clockwise direction of rotation has positive values of said angle .theta., said toner has an apparent density of 0.3 g/cc or higher, and the restoring force of said fin is a function of said angle .theta..