GADGET TO FIX ROTARY CUTTING TOOL IN DUCT OF CUTTING TOOL HOLDER

FIELD: mining industry. SUBSTANCE: invention is meant for fixing rotary cutting tools in ducts of cutting tool holders of actuating elements of mining machines predominantly. Proposed gadget has split cylindrical bushing made from elastic material. End face surfaces of split bushing form duct for passage of culm. Each end face surface of bushing has shape of helical surface. Projection of rib formed by crossing of one of bases of bushing with one of its end face surfaces on one of bases of bushing is displaced relative to projection of rib formed by crossing of another base of bushing with same end face surface on same base of bushing by not less than distance between end face surfaces of bushing in its working position. EFFECT: improved rotation conditions of rotary cutting tool in cutting tool holder and decreased irregularity of wear out of units and parts of cutting tool unit. 7 cl, 8 dwg