MILL Russian patent published in 1998 - IPC

FIELD: mechanical treatment of loose materials; civil engineering; metallurgy, chemical and other industries. SUBSTANCE: mill includes housing with working member made in the form of toroidal helical spirals inserted one in other; one spiral is sectional; it consists of at least two turns having rectangular section which are mutually shifted in radial direction; each of them is engageable with turns of other toroidal helical spiral. Surface of each turn of sectional spiral may be made with identical curvature at zone of engagement with surfaces of turns of other spiral. EFFECT: increased productivity and intensification of grinding process. 2 cl, 4 dwg