CUTTER UNIT

FIELD: mining machinery and equipment. SUBSTANCE: cutter unit is used in operating members primarily of mining machines intended for crushing of hard mineral matter and artificial materials. Cutter unit has following components: cutter holder with through-hole, cutter with working head and holder, insert made of hard-alloy material secured on working head, bush, device for fixing bush in hole of cutter holder, and device for preventing falling of cutter out from bush. Cutter is installed for possible rotation around its longitudinal axis of symmetry. Working head is made with thrust surface of circular configuration located on base of working head. Holder is of cylindrical configuration and is provided with two steps which are made conjugated by adapter section. Diameter of steps is successively increased in direction towards working head. Bush is made with circular protrusion in its end-face and with hole of stepped configuration. Bush is located in hole of cutter holder. Circular protrusion creates supporting surface of circular form. Maximal diameter of thrust surface is not less than 1.2 and not larger than 1.8 of diameter of largest step of holder. Diameter of smallest step of holder is not less than 0.6 and not larger than 0.9 of diameter of largest step of holder. Length of largest step of holder is not less than 0.25 and not larger than 0.50 of bush length. Application of aforesaid embodiment of cutter unit improves condition of cutter rotation and reduces non-uniformity of wear of components and parts of cutter unit. EFFECT: higher efficiency. 12 cl, 5 dwg