Patent ID: 8855526

Claim:
A developing device comprising: a casing including a restricting wall and a bottom wall; a developing roller mounted on the casing, and having a rotational axis extending in an axial direction and a peripheral surface configured to carry developer, the developing roller being configured to rotate in a rotational direction about the rotational axis; a seal provided between the casing and the developing roller to prevent the developer from leaking between the peripheral surface and the casing, the seal being placed on the bottom wall, the seal including: a film member opposed to the peripheral surface of the developing roller, and an elastic member provided between the film member and the casing, the elastic member configured to press the film member against the peripheral surface of the developing roller; and a pair of side seal members, each side seal member provided outside of a respective end of the seal in the axial direction, and the pair of side seal members provided between the casing and the peripheral surface of the developing roller to prevent the developer from leaking from between the peripheral surface of the developing roller and the seal, wherein each of the pair of side seal members presses a respective end of the elastic member in the axial direction, wherein the restricting wall protrudes from the bottom wall toward the developing roller and is provided downstream of the seal in the rotational direction, the restricting wall configured to restrict the seal from moving in the rotational direction, and wherein the film member has a length in the axial direction greater than a distance between the pair of side seal members, each end portion of the film member in the axial direction being provided on a respective seal member of the pair of side seal members.