Patent ID: 9708765
Date: 2017-07-18
CPC Classifications: D21D

Claim:
1. A refining plate segment for a mechanical refiner of lignocellulosic material comprising: a refining surface on a first substrate, wherein the refining surface is adapted to face a second refining surface on a second substrate of an opposing refiner plate, the refining surface including bars and grooves between the bars, wherein an angle of each bar with respect to a radial line corresponding to the bar increases at least 15 degrees along a radially outward direction, and the angle is a holdback angle in a range of 10 to 45 degrees at the periphery of the refining surface, wherein the bars each include a trailing sidewall extending from an upper surface of the bar to the first substrate, wherein a smooth surface extends the length of the trailing sidewall; wherein the bars each include a leading sidewall having an irregular surface, wherein the irregular surface includes teeth extending outwardly from the sidewall towards a sidewall on an adjacent bar and the irregular surface extends radially inwardly along the bar, wherein the teeth each include a first surface extending from the first substrate towards a top of the bar with the teeth and a second surface extending from the first surface to the top of the bar, wherein a slope of the first surface with respect to the first substrate is smaller than a slope of the second surface, wherein each of the teeth includes a corner formed at an interface of the first surface, the first substrate, a third surface extending from an edge of the first surface to the first substrate, and wherein the third surface forms an oblique angle with respect to the trailing sidewall of the bar such that the third surface and the corner associated with the third surface project obliquely from the leading sidewall into the groove.