Patent ID: 6466760
Filing Date: 2002-10-15
Classification: G03G

Abstract:
A development device comprising:a development roller, a surface of which is made of electrically resistant material; a blade that comes in contact with the development roller so as to form a layer of developing agents, and has a predetermined thickness on the development roller, and possesses electrical conductivity; a development bias power supply that applies a bias to the development roller and the blade; a reset roller that feeds developing agent to the development roller and collects residual developing agents on the development roller by utilizing a potential difference; and a resistor provided between the blade and the development bias supply to establish electric connection therebetween, said resistor having a resistance R determining &tgr;=CT(RD+R) where CT is an equivalent capacitance of the layer of developing agents at a contact region having a nip width between said development roller and said blade, RD is an equivalent resistance of said development roller, and &tgr; is a time constant of a closed circuit including a capacitor corresponding to the layer of developing agents having the equivalent capacitance, said resistor, and a resistor corresponding to said development roller having the equivalent resistance RD, said resistance R being smaller than 100 M&OHgr;, and the time constant &tgr; being larger than a time period for said development roller to run by the nip width between said development roller and said blade.