Adjustable indexing roller mechanism

A sheet feeding mechanism comprising a singulating assembly means for accumulating sheets in a stack adjacent the singulating assembly, said singulating assembly comprising a retard roller, said retard roller having a first bearing surface at a lower position, means for feeding single sheets from the stack past and beneath the bearing surface of the retard roller, said retard roller being adjustable to move the said first bearing surface away from its lower position and replacing it with a second bearing surface at said lower position, a singulating roller is mounted beneath the said bearing surface of said retard roller, said sheet feeding means adapted to move said sheets between said bearing surface and said singulating roller, said sheets being fed from the bottom of the stack, said sheet feeding means comprises at least one belt on which said sheets are stacked, said singulating assembly comprises a guide brake in front of said retard roller, said sheets being stacked against said guide brake height adjusting means are provided to adjust the height of the singulating assembly relative to said belt and singulating roller, said singulating roller comprises a plurality of resilient splines extended therefrom means for holding the retard roller in a predetermined position with its bearing surface in its lower position opposite the singulating roller, said guide brake is located above the belt, an adjustment dial is mounted adjacent the roller, said dial being rotated in order to rotate the roller to present said second bearing surface to its lower position opposite said singulating roller.