Patent ID: 6918582

Claim:
A sheet feeder for feeding individual sheets, one at a time, into a sheet handling machine, said sheet feeder comprising: a platform having a front edge and a back edge for supporting a stack of said sheets; and a feed head assembly positioned adjacent said front edge of said platform and adapted to acquire an individual sheet from said stack and feed said acquired sheet off said front edge of said platform, said feed head assembly comprising: a vacuum plenum positioned towards said front edge of said platform; a port plate closing said vacuum plenum and positioned substantially parallel to said sheets in said stack on said platform, said port plate having a front edge substantially aligned with said front edge of said platform; a plurality of spaced ports through said port plate through which air can flow into said plenum; means within said plenum for restricting the air flow through some of said plurality of ports in said port plate; and at least one belt having openings therethrough mounted for movement through a closed loop around said vacuum plenum and across said port plate so that when openings in said at least one belt align with any of said plurality of spaced ports in said port plate, air can flow through the aligned holes in said belt and said spaced ports in said port plate to thereby acquire and remove the acquired sheet from said stack on said platform.