Patent ID: 7708265

Claim:
A sheet feeder comprising: a housing having a cassette housing part, the cassette housing part recessed horizontally from a front surface of the housing toward a depth direction, and having a pick-up roller that is driven rotationally about a horizontal axis perpendicular to the depth direction provided in an upper part at the front surface side within an opening of the housing; a sheet feed cassette that has a holding chamber having an open top for storing stacked sheets, the sheet feed cassette configured to be housed within the cassette housing part and drawn from the cassette housing part; a pressure plate provided pivotably about a pivot in parallel with the horizontal axis so as to be inclined downwardly toward the depth direction of the sheet feed cassette; a pressure mechanism that presses the sheets against the pick-up roller by increasing an angle of inclination of the pressure plate when the sheet feed cassette is pushed into the cassette housing part; and a pressure plate regulation mechanism that inclines the pressure plate downwardly toward the depth direction while separating the sheets on the pressure plate or the pressure plate from the pick-up roller when the sheet feed cassette is drawn from the cassette housing, wherein the pressure plate regulation mechanism has a drive gear provided at the cassette housing part side and a driven gear provided at the sheet feed cassette side, the drive gear meshing with the driven gear when the sheet feed cassette is housed in the cassette housing part, wherein the pressure plate regulation mechanism has at least one spring provided at the sheet feed cassette side and configured to push the pressure plate in an upward direction, wherein when the sheet feed cassette is housed in the cassette housing part, the driven gear is driven by the drive gear and pushes up the pressure plate without the spring pushing the pressure plate, and wherein when the sheet feed cassette is drawn from the cassette housing part, the spring pushes up the pressure plate while the driven gear is separated from the drive gear and without the driven gear pushing up the pressure plate.