Patent ID: 7444087

Claim:
An image forming apparatus comprising: an image forming apparatus body that forms image on a recording medium; and a developer cartridge that is removably mounted on the image forming apparatus body, wherein the developer cartridge comprises: a developer reserving chamber that reserves a developing agent; a developing side electrode that is configured to be applied with a developing bias; a developer carrier that carries a developing agent in the developer reserving chamber to an image carrier when the developing bias applied to the developing side electrode is received; and a power supply shielding mechanism that electrically connects the developing side electrode and the developer carrier and shields the power supply between the developing side electrode and the developer carrier by an irreversible shielding operation, and wherein the image forming apparatus body comprises: a determination unit that determines whether or not a lifetime of the developer cartridge is elapsed; an application unit that applies the developing bias to the developing side electrode; and an execution unit that causes the power supply shielding mechanism to execute the shielding operation when the determination unit determines that the lifetime of the developer cartridge is elapsed.