Patent ID: 8439343

Claim:
An image forming apparatus configured to form an image on first sheets of a first size and second sheets of a second size, the first size being larger than the second size, each of the sheets including a leading edge and a trailing edge opposite to the leading edge, the image forming apparatus comprising: a housing; a cassette detachably accommodated in the housing and configured to store the sheets; a feeding unit configured to feed the sheets so that the leading edge precedes the trailing edge; and an image forming unit configured to form the image on the sheets fed by the feeding unit, wherein the cassette includes: a first wall along the trailing edge, a second wall along the leading edge, a first bottom plate extending from the first wall toward the second wall, a second bottom plate extending from the second wall toward the first wall, and an intermediate wall configured to rotate up and down between a first position in which the intermediate wall connects the first bottom plate with the second bottom plate and a second position in which the intermediate wall disconnects the first bottom plate and the second bottom plate, the first and second bottom plates are independently withdrawable from the housing when the intermediate wall is in the second position, the first wall, the second wall and the first and second bottom plates form a first storage space configured for storing the first sheets when the intermediate wall is in the first position, and the intermediate wall in the second position partitions the first storage space into two second storage spaces, each of which is configured for storing the second sheets, the feeding unit includes a first lift plate and a second lift plate disposed respectively in the two second storage spaces, an elevating mechanism configured to move the first and second lift plates and first and second pick-up rollers corresponding respectively to the two second storage spaces, the elevating mechanism moves one of the first and second lift plates which support the second sheets into a position where the respective first or second pick-up roller draws out from the cassette one of the second sheets when the intermediate wall is in the second position, and the elevating mechanism simultaneously moves both of the first and second lift plates which together support the first sheets when the intermediate wall is in the first position.