Sheet supply apparatus.

摘要

The present invention provides a sheet supply apparatus comprising a lifter means for maintaining a height of an upper surface of a sheet stack supported by a sheet supporting means substantially constant by lifting or lowering the sheet supporting means, and a supply means for feeding out an uppermost sheet from the sheet stack maintained in a constant height position by the lifter means, and wherein the lifter means comprises a clutch means for transmitting a predetermined amount of rotation from a drive gear, a rock means for rocking a ratchet pawl by the rotation transmitted by the clutch means, a ratchet gear engageable by the ratchet pawl and rotated by a rocking movement of the ratchet pawl, a lifter member connected to the ratchet gear and adapted to lift the sheet supporting member by rotation of the ratchet gear, and an actuation means shifted in accordance with the height of the upper surface of the sheet stack rested on the sheet supporting means and adapted to actuate the clutch means when the height of the upper surface of the sheet stack is below a predetermined height.