Sheet feeding device

Claim 1

A sheet feeding device for removing and transporting individual sheets from the bottom of a stack comprising a base, spaced upstanding side plates on said base, a first conduit secured to one of the side plates, a second conduit secured to the other side plate, a suction roller assembly rockably carried between the first and second conduits to form a continuous passage therebetween, said roller assembly comprising a hollow cylindrical member having a plurality of elongated spaced openings therein, spaced end plates disposed at each end of the cylindrical member, spaced openings in each of the end plates, said cylindrical member being positioned against the bottom sheet of the stack, a first and second valve plate having openings therein carried by the first and second conduits in frictional contact with the end plate adjacent thereto, said valve plate openings being of a size and disposition such that the combined valve plates and end plates form cut-off valves at each end of the roller assembly, a source of air under pressure connected to the first conduit, a source of vacuum connected to the second conduit, spaced rollers freely carried by the conduits beneath the stack, a driven roller in tangential contact with the spaced rollers, means to rock the roller assembly to alternately open and close the cut-off valves to draw down the leading edge of the bottom sheet of the stack by suction, carry the sheet into the nip of the spaced and driven rollers, and free the trailing edge of the sheet after the sheet has entered the nip, and means to transport the sheet after it leaves said nip.