Patent ID: 7428393

Claim:
A developing device, detachably arranged in a main body of an image forming apparatus having a toner conveyance portion formed with a hole portion and equipped with a hole portion shutter for opening and closing the hole portion, the developing device comprising: a developer container for containing a developer; a toner replenishing portion configured to detachably connect with the toner conveyance portion and to communicate with the developer container via an opening portion to supply the developer container with toner; wherein the toner replenishing portion is provided above the developer container and is equipped with an opening portion shutter for opening and closing the opening portion, such that the opening portion shutter opens or closes the opening portion and, at the same time, the hole portion shutter opens or closes the hole portion of the toner conveyance portion, respectively; a removable sealing member for sealing the opening portion until the developing device is used on the main body; and a removable second sealing member for isolating a space where the developer is contained from an adjacent space where a developing roller is installed, until use of the developing device on the main body is started.