Patent ID: 7300008

Claim:
A refiner plate comprising: concentric rows of teeth, wherein each tooth in the rows is a pyramidal projection on the plate having sloped front and rear surfaces form a tooth top surface, the top surface having a width extending generally perpendicular to a radius of the plate extending through the tooth; a feed angle formed on teeth in a plurality of rows, wherein the feed angle is formed by a leading edge of the tooth; and a feed angle for a first row of teeth differs from a second feed angle for a second row of teeth, wherein the second row of teeth are one of an outer four rows of teeth on the plate, the second row of teeth have a feed angle of at least 5 degrees, and the difference between feed angles is at least 20 degrees, wherein the concentric rows of teeth on the refiner plate interleave with concentric rows of teeth on an opposing refiner plate in a refiner.