Patent ID: 7458574

Claim:
A leveling device for a stacking tray that compensates for end-to-end thickness variations in a stack of non-uniform thickness media and reduces a valley in the stack, comprising: a pivoting stack tray that receives the stack of non-uniform thickness media thereon, one end of the tray configured to receive and contact a thicker end of the stack and being pivoted relative to an opposite end thereof between full tray and empty tray positions to provide level top ends of the stack; and a valley removal mechanism mounted to the pivoting stack tray, the valley removal mechanism including: a media support surface positioned above the pivoting stack tray intermediate ends of the pivoting stack tray and below the stack, the media support surface supporting at least a portion of an intermediate section of the stack and being pivotally movable relative to the pivoting stack tray; a ramp surface having a predefined profile; and at least one lever arm operably connected between the media support surface and at least one ramp follower to move the media support surface relative to the pivoting stack tray in accordance with the ramp surface profile and in proportion to the height of the stack to offset a valley formed intermediate ends of the stack and provide a top media in the stack with a substantially flat top surface profile, wherein the pivoting stack tray moves with a combination of pivoting and translatory movement between the full tray and empty tray positions and the ramp profile guides the media support surface to compensate for the combination movement of the pivoting stack tray.