Suction belt separator for flat items

Claim 1

A suction belt separator for separating flat items from a stack and for moving them along a conveying path, comprising, in combination: means defining a region in which the stack is placed; a first suction chamber disposed opposite the stack region, said chamber having a suction opening communicating with the stack region, a control opening spaced along the conveying path from said suction opening by a distance not greater than the length of the shortest item to be conveyed, and a throttle opening communicating with the atmosphere; a second suction chamber disposed on the opposite side of the conveying path from said first chamber, said second chamber being urged resiliently toward said first chamber and having a suction opening disposed opposite said control opening and forming therewith a control channel extending across the conveying path; a vacuum source connected to said second chamber; and a moving belt moving along the conveying path and across said suction and control openings at the same side of the conveying path as said first chamber, said belt having a series of suction perforations in line with said openings; whereby: said suction opening of said first chamber is in communication with said vacuum source only through said control channel; an item can be taken from the stack and conveyed by said belt only when a suction exists at said suction opening of said first chamber; and the suction at said suction opening of said first chamber is interrupted when an item intersects said channel so as to block communication between said control opening and said second chamber suction opening.