The Motion of a Sheet of Paper (3)

Abstract

The motion of sheet paper inside the printing machine is analyzed by using mechanical and fluid dynamic equations under gravity. In this analysis the paper is divided into small elements, each of which is affected by two kind of dynamic forces. The momentum transfer force from air to paper element is only considered as the effect of air motion for simplicity. Two cases of the motion are investigated, one of those is on a delivery chain and the other is on a transfer cylinder. For each case, two types of fluid conditions are considered. One is under natural air flow condition caused by paper motion and the other is under a forced air flow generated by fans or air nozzles. The dynamic behaviour of sheet paper in printing machine can be approximately simulated by this analysis. The result of simulated movement of sheet paper clearly shows how the air flow from the fan controls the fluctuation of the motion on a free sheet edge.