Patent ID: 7766325
Filing Date: 2010-08-03
Classification: B65H

Abstract:
1. An apparatus for rotating a sheet moving in a first direction, the apparatus comprising: at least one first roller rotatable against a first side of a sheet, the at least one first roller having a first drive; at least one second roller rotatable against the first side of the sheet, the at least one second roller having a second drive that is capable of rotating the at least one second roller independently of the at least one first roller, the at least one second roller being spaced a distance from the at least one first roller in a direction perpendicular to the first direction; at least one counter roller configured to for contact a second side of the sheet opposite the first roller; a controller configured to control the first and second drives to rotate the sheet around an axis substantially perpendicular to a plane of the sheet; and a trailing edge sensor, the sensor configured to sense a trailing edge of the sheet as it moves in the first direction; wherein the controller is configured to cause the rollers to rotate the sheet 180 degrees in response to said sensing, such that leading and trailing edges of the sheet are interchanged; and wherein the controller is configured to time rotation of the sheet using input from the trailing edge sensor to position a leading edge of the sheet at a same position irrespective of a length of the sheet, so that the first and second rollers position a leading edge of a longer sheet and a leading edge of a shorter sheet at a same location that is independent of sheet length.