Patent ID: 7715764

Claim:
A developing device provided in an image forming apparatus including a photoreceptor, for supplying a toner onto an electrostatic latent image on the photoreceptor, comprising: a developer bearing member rotatably provided so as to face the photoreceptor, for supplying the toner onto the electrostatic latent image on the photoreceptor; a developer tank including a developing area tank having a length substantially equal to a length in an axis line direction of the developer bearing member, for supplying a developer to the developer bearing member, and an agitating tank provided so as to be connected to the developing area tank in a longitudinal direction of the developing area tank, the agitating tank having a toner replenishing port for receiving toner; a first agitating member rotatably supported by the developer tank so as to face the developer bearing member, the first agitating member having a length longer than a length of the developer bearing member in its axis line direction, and being provided so that a first end thereof reaches a vicinity of an outer side end of the agitating tank in its longitudinal direction and having a second end thereof that reaches a vicinity of an outer side of the developing area tank opposite the agitating tank, the first agitating member agitating and transporting the developer from the first and second ends inwards toward the toner replenishing port; a second agitating member rotatably supported by the developer tank so as to oppose the developer bearing member via the first agitating member, the second agitating member having a length longer than a length in the axis line direction of the developer bearing member, and being provided so that a first end thereof reaches a vicinity of the outer side end of the agitating tank and having a second end thereof that reaches a vicinity of the outer side of the developing area tank opposite the agitating tank, the second agitating member agitating the replenished toner along with the developer in the developer tank and transporting the mixture; and a toner hopper disposed so as to be connected to the developer tank, for supplying the developer tank with toner received from a toner storing container, the toner hopper having a a toner supplying port in communication with the toner replenishing port of the developer tank.