Patent ID: 6189883
Filing Date: 2001-02-20
Classification: B65H

Abstract:
A pneumatic sheet feeder for feeding individual sheets from a sheet stack, comprising:a feed deck for supporting the sheet stack;a pair of spaced apart parallel guide rails on the feed deck for receiving the sheet stack between the guide rails; anda pneumatic assembly mounted in proximity to a sheet feeding end of the feed deck operative to feed individual sheets from the sheet stack, the pneumatic assembly including:an outer rotatably mounted feed drum having an outer and inner circumference and a plurality of suction openings extending between the inner and outer circumferences wherein at least a portion of the outer circumference extends above a planar surface of the feed deck;an inner vane cylinder having an outer and inner circumference with a vane cutout portion extending between its outer and inner circumference wherein the inner vane cylinder is received within the inner circumference of the feed drum such that the vane cutout portion is in communication with the suction openings extending above the planar surface of the feed deck; anda rotating inner valve cylinder having an outer and inner circumference with a valve cutout portion extending between its outer and inner circumference rotatably received within the inner vane drum, whereby when the valve cylinder is rotated such that its valve cutout portion is in communication with the vane cutout portion, and a vacuum is applied to the inner circumference of the valve cylinder, air is caused to be suctioned downward through the suction openings of the feed drum so as to cause a sheet on the bottom of the paper stack to adhere against the rotating feed drum and convey away from the sheet stack.