Patent ID: 7371041

Claim:
An apparatus for forming stacks of articles, comprising: a first article feeder station presenting a plurality of first articles at a first loading position; a second article feeder station presenting a plurality of second articles of a characteristic different size than the first articles at a second loading position; and a bidirectionally rotatable turret assembly comprising: a first stacker arm supported by the turret assembly and selectively movable in either a clockwise direction or a counterclockwise direction to a selected one of the first and second loading positions; and a second stacker arm supported by the turret assembly and responsively movable, by the selected movement of the first stacker arm, to another loading position; and end effectors independently operable on each of the stacker arms, each end effector having a mandrel sized to simultaneously support a plurality of the first and second articles from the respective feeder stations to form alternating stacks of the first and second articles on both stacker arms.