摘要 |
Device incorporating rollers to separate particles of different gradings a plurality of adjacent rollers (11) forming a selection bed where each roller (11) has a surface conformation defining a plurality of circumferential peaks (12) alternating with circumferential grooves (13), the rollers (11) including at least a working position where the grooves (13) of one roller are facing and at least partly penetrated by the peaks (12) of the adjacent roller (11), the discharge gap (18) between the two adjacent rollers (11) having a substantially zig-zag development, in at least some rollers (11) the connection surface (26) between the peaks (12) and grooves (13), and/or the peaks (12) and/or the grooves (13) themselves being at least partly worked with protuberances, protrusions, hollows and/or facets (23, 24, 25). |