Patent ID: 8573584

Claim:
An image forming apparatus comprising: a sheet container at least partially withdrawable from the image forming apparatus to a sheet supply position and including a platform member on which a sheet is placed, the platform member being hinged between a sheet feed position in which the sheet placed on the platform member contacts a sheet feed unit provided to the image forming apparatus and a lower position lowered from the sheet feed position, the platform member being located at the lower position upon withdrawal of the sheet container from the image forming apparatus by a predetermined distance; a sheet stacking member on which a sheet discharged from the image forming apparatus is stacked, the sheet stacking member hinged to the image forming apparatus to closably open the sheet container; a restriction unit to restrict a swinging movement of the sheet stacking member in a state in which the platform member is located at the sheet feed position and allow the swinging movement of the sheet stacking member in a state in which the platform member is located at the lower position; and a stopper mechanism to restrict insertion of the sheet container into the image forming apparatus in a state in which the sheet stacking member swings open from the sheet container, the stopper mechanism comprising: a stopped member provided to the sheet container, the stopped member being movable vertically along the swinging movement of the sheet stacking member and being lifted from the sheet container toward the sheet stacking member in the state in which the sheet stacking member swings open from the sheet container; and a stopper member provided to the image forming apparatus, the stopper member being contactable with the stopped member at a portion inside the sheet container in a width direction perpendicular to a direction of withdrawal of the sheet container, the stopped member comprising: a stopped surface contacted by the stopper member in a state in which the stopped member is lifted; and a switching surface adjacent to the stopped surface, the switching surface vertically moving the stopped member by contact against the stopper member.