Patent ID: 7883037
Filing Date: 2011-02-08
Classification: D21D

Abstract:
1. A method of refining celluosic fiber material between opposing discs in a refiner, wherein each disc has concentric rows of teeth, the method comprising: rotating at least one of the discs with respect to the other disc and about an axis concentric to the discs; feeding the fiber material to between the discs; propelling the fiber material fed between the discs radially outward through a gap formed by the concentric rows of teeth and wherein the rows on the opposing discs intermesh; refining the refining material by passing the material through the gap and rows of the intermeshing teeth; and deflecting the refining material as the material flows through an outer row of teeth on one of discs, wherein the at least one of the disc has an outer row in which each tooth has a leading sidewall angled to deflect pulp material moving radially through the gap and an inner row of teeth radially inward of and adjacent to the outer row, wherein each tooth in the inner row has a leading sidewall parallel to a radius of the at least one disc.