Back to results
US 2001/0036376 A1Published application
Toner supply roller and developing apparatus
AssigneeBridgestone Corporation
InventorsHirotaka Yamazaki, Junji Sakata
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeBridgestone Corporation
InventorsHirotaka Yamazaki, Junji Sakata
Estimating the term…
There are disclosed a toner supply roller which is composed of a foamed elastic body, and has a compression spring constant of 0.25 to 5.0 N/mm, and preferably has the number of cells per a length of 25 mm being 50 to 1200 in the foamed elastic layer; a developing apparatus which is equipped with the above toner supply roller and capable of affording images free from defect such as unevenness in pitch, density, etc.; another developing apparatus which is equipped with a toner supply roller and a developing roller, each being electroconductive, and which satisfies the requirement that the electric resistance of the toner supply roller is always lower than that of the developing roller at an impressed voltage of 100V to 500V, thereby enabling formation of satisfactory images by favorable electrification with the toner supply roller due to favorable adsorption of a toner onto the developing roller; and an image formation apparatus equipped with any of the above developing apparatuses.
A toner supply roller that is composed of a foamed elastic body and is mounted on a developing apparatus which has a toner cartridge housing a toner as a developer, a toner supply roller and a developing roller, and which forms a toner image by supplying an electrostatic latent image on the surface of a photosensitive body with the toner, characterized in that said toner supply roller has a compression spring constant in the range of 0.25 to 5.0 N/mm.
A developing apparatus which has a toner cartridge housing a toner as a developer, a toner supply roller and a developing roller, and which forms a toner image by supplying an electrostatic latent image on the surface of a photosensitive body with the toner, characterized in that the toner supply roller that is composed of a foamed elastic body has a compression spring constant ranging from 0.25 to 5.0 N/mm and smaller than that of the developing roller, that when the developing roller is in butt contact with the toner supply roller, the deformation of the developing roller is substantially due to the deformation of the toner supply roller, that the cutting amount in the toner supply roller by the developing roller is in the range of 0.5 to 2 mm, and that the pressing force against the developing roller is at most 6.0N.
A developing apparatus which has a toner cartridge housing a toner as a developer, a toner supply roller and a developing roller, and which forms a toner image by supplying an electrostatic latent image on the surface of a photosensitive body with the toner, characterized in that both the toner supply roller and the developing roller are electroconductive, and that the electric resistance of the toner supply roller is always lower than the electric resistance of the developing roller at an impressed voltage in the range of 100V to 500V.
Dependencies are inferred from the claim text.