Patent ID: 7694951

Claim:
A sheet feeder comprising: a first cassette comprising an accommodating section that is capable of accommodating a stack of first recording medium; a feed roller that feeds the first recording medium one sheet at a time in a feeding direction; and a second cassette disposed on the first cassette above the accommodating section, the second cassette configured to move with respect to the first cassette between a first position and a second position downstream of the first position with respect to the feeding direction, the second cassette comprising a mounting section capable of holding a stack of second recording medium having a size different from a size of the first recording medium, wherein the feed roller contacts the second recording medium held by the second cassette when the second cassette is located at the second position; the mounting section of the second cassette comprises a first portion and a second portion, the second portion being displaceable relative to the first portion between a closed position and an open position, wherein the second portion exposes the accommodating section wider in the open position than in the closed position and both the first portion and the second portion move with respect to the first cassette between the first position and the second position; and the first portion is capable of engaging with and disengaging from the first cassette.