Feed Roll Self-Energization Eliminator
Original Publication Date: 1985-Nov-01
Included in the Prior Art Database: 2005-Feb-19
In a web drive system, the installation on the feed roll shaft, adjacent to each feed roll segment, of non-driven, freely rotating disks slightly larger in diameter than the feed roll, eliminates the self- energizing effect caused by wrapping the web around the feed roll, and minimizes the variability in web drive tension. Fig. 1 shows a typical printer web drive system in which the paper 1, a continuous form with pin-feed holes at the edges, is metered incrementally by pin-feed tractor 2 to feed roll 3 and pressure roller 4, which are continuously applying torque to the web. The output web tension, T1, must be closely controlled to prevent it from becoming much greater than input web tension, T2, causing the web to over-ride the pin-feed, with resulting damage to the pin-feed holes and/or mis- feeding or jamming.