Web tension control apparatus and method

摘要

A web tension control and apparatus uses a lightweight dancer and a control system that detects web tension using the dancer position as well as downstream sensors to maintain a relatively constant web tension. The control system also adjusts the braking force to an unwind roll based on the diameter of the roll, allowing for greater web tension control. A two-phase braking system prevents the unwind roll from spilling excess paper into the production line.