Patent ID: 8478140
Filing Date: 2013-07-02
Classification: G03G

Abstract:
1. An image forming apparatus comprising: an image bearing member on which an electrostatic latent image is to be formed; a developing device for developing the electrostatic latent image by supplying a developer to said image bearing member, said developing device including: a developer container for containing the developer; a rotatable developer carrying member, including a first electrode member, for carrying and supplying the developer to said image bearing member; and a developer supplying member, which is provided in contact with said developer carrying member and includes a surface foam layer and a second electrode member for rotatably supporting said developer supplying member, for supplying the developer to said developer carrying member; a measuring device capable of measuring a remaining developer amount in said developer container by detecting electrostatic capacity between the first electrode member and the second electrode member; and a replenishing device for performing a replenishing operation for replenishing said developer supplying member with the developer by rotating said developer supplying member while applying a DC bias between the first electrode member and the second electrode member so that a value obtained by subtracting an electric potential of the second electrode member from an electric potential of the first electrode member has an identical polarity to a normal charge polarity of the developer, wherein when the remaining developer amount measured by said measuring device is not more than a threshold, the replenishing operation is performed by said replenishing device and thereafter the remaining developer amount is measured again by said measuring device.