Patent ID: 7458927
Filing Date: 2008-12-02
Classification: B65H

Abstract:
1. An interfolding apparatus for interfolding first sheets of a first web of sheet material moving in a downstream direction along a first web path with second sheets from a second web of sheet material moving in a downstream direction along a second web path, with each of the first sheets having a leading edge and a trailing edge substantially spaced an unfolded length of the first sheets from one another along the web path and a middle portion disposed along the web path substantially halfway along the unfolded length of the first sheets between the leading and trailing edges of the first sheets, the apparatus comprising: a knife roll for cutting the first sheets from the first web of sheet material, first and second interfolding rolls for interfolding the first and second sheets with one another, and a transfer roll for transferring the first sheets from the knife roll to the first interfolding roll and forming a pre-bend in the middle portion of the first sheets in cooperation with the knife roll; the knife roll being rotatable about a first axis in a first direction, the transfer roll being operatively connected to be rotatable in a second direction opposite the first direction about a second axis extending substantially parallel to the first axis, the first interfolding roll being operatively connected to be rotatable in the first direction about a third axis extending substantially parallel to the first and second axes, and the second interfolding roll being operatively connected to be rotatable in the second direction about a fourth axis extending substantially parallel to the first, second and third axes; the knife roll and transfer roll having respective peripheries thereof with portions of their respective peripheries defining respectively a knife-roll-portion of the web path and a transfer-roll-portion of the web path cooperatively disposed and rotationally timed such that the first sheets travel sequentially from the knife-roll-portion to the transfer-roll-portion of the web path with their respective leading edges disposed downstream from their respective trailing edges at substantially the unfolded length from their respective trailing edges along the knife roll; the periphery of the knife roll having a pre-forming groove therein and the transfer roll having a corresponding pre-forming blade thereof configured and operatively connected to the knife roll in timed rotation therewith for pressing the middle portion of each first sheet into the pre-forming groove in the knife roll, to thereby pre-form a bend into the middle portion of each sheet; the first interfolding roll including a gripper therein for grasping each first sheet along the pre-formed bend and forming an interfold along the pre-formed bend in each first sheet, whereby the pre-formed bend facilitates interfolding of the first and second sheets.