SHEET FEED DEVICE

PROBLEM TO BE SOLVED: To make it possible to feed a sheet without unreasonably producing many 'double feed' by providing a friction type unitization device between a throat knife gate and a lower stream additional conveyor, in a vacuum shuttle sheet feed device. SOLUTION: A driving belt operates a valve 68 to make vacuum ON before a shuttle plate 52 reaches the rightmost position, and pulls out a frontmost sheet a little on the right side before feeding the frontmost sheet in the sheet separation direction on the left side. Simultaneously, the driving belt drives continuously the conveyor belt 156 of a sheet feed shift tray 14. When a vacuum groove is made vacuum, the frontmost sheet 56 is pulled a little downward to a throat 192 directly under the separation lower end part of a knife gate 112, hence the frontmost sheet is passed under the knife gate 112 by movement of the shuttle plate 52 in the separation direction, and finally enters the feed nip 190 between driven and play feed rollers 94, 96 through a high friction roller 118 and a unitization gap 188.