Patent ID: 7758040

Claim:
A sheet feed cassette comprising: a main container on which sheets are mounted; a sub container slidably attached to the main container; first slidable portions that are disposed on sidewalls of each of the main container and the sub container, and that are formed in a U-shape; a rear end guide that is disposed on the sub container, that regulates a rear end of the sheets, and that is slidable in a direction of an extraction and a retraction of the sub container from the main container; and a size detector that is coupled with the rear end guide, and that detects a size of the sheets, the size detector comprising: a hole for allowing a rotary motion; a continuous groove formed in a zigzag; a pin disposed on the rear end guide; a sensor; and an uneven part for detecting a radial position of said size detector, wherein the hole mates with the main container, and wherein the pin is disposed in the continuous groove.