System and process for controlling the deceleration and acceleration rates of a sheet material in forming absorbent articles

摘要

A system and process for unwinding materials in forming absorbent articles is described. The system includes an unwind device in association with a festoon. The festoon is for accumulating a determined length of material. The amount of material contained in the festoon is increased or decreased depending upon the rate at which a roll of material is unwound in relation to the rate at which the first material is fed into a downstream process. In order to minimize the capacity of the festoon and in order to minimize tension swings in the festoon, the festoon includes a plurality of drive devices associated with selected guide rolls contained in the festoon. The drive devices can accelerate and/or decelerate the guide rolls in response to rate increases or decreases occurring at the unwind device in relation to the downstream process speed. In one embodiment, each of the guide rolls is controlled independently of the remaining guide rolls in the festoon.