Patent ID: 8360416

Claim:
A sheet remaining amount detection device, comprising: sheet storage unit which stores sheets and in which a sheet pickup position where the sheets are picked up is set beforehand; a tray on which the sheets are to be placed and which is provided in the sheet storage unit in such a manner as to be vertically movable between the sheet pickup position and a lowest position lower than the sheet pickup position; a rope connected to the tray; a pulley which includes a shaft and on which the rope is taken up with the winds of the rope aligned in an axial direction of the shaft; a motor for moving the tray upward by rotating the pulley about the shaft in a direction to take up the rope to locate the uppermost one of the sheets placed on the tray to the sheet pickup position; a position detector for detecting a present position of the rope on the pulley in the axial direction; and a remaining amount detecting section for detecting the remaining amount of the sheets placed on the tray based on the present position of the rope detected by the position detector.