Patent ID: 6985265

Claim:
An image forming device for forming images on sheets, the image forming device comprising: a main body and a sheet-supply cassette attachable to and detachable from the main body, the sheet-supply cassette including: a guide that guides edges of sheets housed in the sheet-supply cassette, the guide being movable to change position in accordance with size of housed sheets; a cam abutment portion that moves to a position that corresponds to the position of the guide; a cam with a cam surface, the cam movable so that the cam surface selectively moves toward and away from the cam abutment portion, the cam moving to a separated position, wherein the cam surface is separated from the cam abutment portion, when the sheet-supply cassette is detached from the main body; and a detected portion that moves in a linked manner with the cam; and the main body including: a cam mover that, when the sheet-supply cassette is attached to the main body, moves the cam until the cam surface of the cam abuts the cam abutment portion; and a detection portion that detects the detected portion moved in a linked manner with the cam; wherein the cam surface has a shape that varies movement amount of the cam into abutment with the abutment portion by the cam mover in accordance with the position of the guide.