The central screw and the outer ribbon are connected to the cycloidal needle wheel reducer, and they rotate at an identical revolution. In operation, the central screw lifts the material from bottom to top; meanwhile, the ribbon with a higher linear velocity spirals to lift the material from bottom to top along the cone wall. The two kinds of motions make the material be thrown into the space tangentially. And the material effects strong convection, shearing and diffusion, thus a quick mixing effect is achieved. (The screw can also be made to a reverse one).