The rotary crusher is composed of transmission, base, eccentric sleeve, crushing cone, middle frame, cross beam, prime mover, oil cylinder, hydraulic pressure, pulley, electrical and dry and thin oil lubrication. The motor drives the eccentric sleeve to rotate through the belt pulley and bevel gear. When the eccentric sleeve rotates, it drives the crushing cone to swing around the center of the crusher. Thus, the crushing conical surface sometimes approaches and sometimes leaves the fixed conical surface, so that the materials fed into the crushing cavity are continuously crushed by extrusion and bending. The crushed material is discharged from the bottom of the crushing chamber by its own weight.