Patent ID: 6234322
Filing Date: 2001-05-22
Classification: B07B,B27N,D21B

Abstract:
A roller device to separate particles of wood or material similar to wood having different gradings from a loose mass in the form of chips, shavings, granules or fibres, the device being able to be employed in separating and screening machines or machines to form layers, and comprising a plurality of rotary rollers disposed with the axes parallel therebetween to define a selection bed, the loose mass being able to advance in a direction substantially at a right angle to the axes of the rollers, each roller having a cylindrical surface shaped to define a plurality of circumferential and sharp peaks disposed side by side to define a plurality of circumferential and V-shaped grooves, said peaks and grooves being arranged substantially parallel to the axis of the selection bed, characterised in that the rollers have at least a working position wherein the peaks of one roller are faced to and deeply penetrated in the V-shaped grooves of the adjacent roller to define a discharge gap for selecting the particles between two adjacent rollers with a substantially zig-zag development, wherein each segment of said discharge gap is inclined with respect to the axes of said rollers, that in at least some of the rollers, the connecting lateral surfaces between the peaks and the grooves are provided with at least protuberances, protrusions, hollows or facets for vibrating the loose mass, so that said zig-zag discharge gap is at least laterally uneven, even if its width is substantially constant.