Patent ID: 8348259

Claim:
A sheet feed apparatus for a document reproduction machine, comprising: a feed device constructed to receive a sheet; a feedbox having an upper portion and a lower portion, a bottom located in the lower portion, and the feed device located at the upper portion of the feedbox; a plurality of plungers located at the lower portion; a vertically adjustable elevator, positioned within the feedbox, and constructed to carry the sheet; a plurality of sensors situated at an upper portion of the feedbox wherein the sensors are activated by a portion of the sheet; a data processing device that receives information from the plurality of sensors; and a single actuating device located below the plurality of plungers, and connected to the plurality of plungers, constructed to receive information from the data processing device, wherein: the plurality of sensors comprises at least four sensors located at positions corresponding to at least four different edges of the sheet; the four sensors are configured to measure a height of the sheet at the corresponding edge of the sheet; each one of the plurality of plungers contacts a different portion of the sheet; the plurality of plungers are constructed to independently adjust the height of the sheet where the plurality of plungers contacts the portion of the sheet; and each plunger of the plurality of plungers adjusts the height of the corresponding portion of the sheet until the four sensors measure the height of the sheet to be the same at each sensor.