Patent ID: 7121994

Claim:
An interfolding machine, comprising; an upstream roll mounted for rotation with a first shaft; first and second folding rolls configured to create a fold in each of a pair of successively fed overlapping sheets, wherein one of the folding rolls is mounted for rotation with a second shaft, wherein the first and second folding rolls are configured to create an alternating oppositely directed fold in each of the pair of successively fed overlapping sheets; a first helical gear secured to the first shaft; a second helical gear secured to the second shaft; and phase adjustment device configured to cause rotational movement of the first shaft through the first gear and the second shaft through the second gear to adjust the position at which a fold is formed in one of the sheets, wherein the phase adjustment device includes an oppositely oriented helical gear arrangement mounted on an axially movable input shaft, wherein axial movement of the input shaft causes rotational movement of the first and second gears through the helical gear arrangement to change the phasing of the upstream roll relative to the folding rolls during operation of the interfolding machine.