Patent ID: 8061636

Claim:
A jet mill in which material introduced into a crushing chamber is comminuted by a swirl flow produced by gas sprayed from a plurality of spraying nozzles disposed along an internal perimeter wall of the crushing chamber, said jet mill comprising: a plurality of spraying nozzles; a movable bearing for pivotally supporting the plurality of spraying nozzles so as to allow movement of the direction in which gas is sprayed from each; an annular movable member that is disposed above or below a row of the nozzles, and is movably supported to swivel in a direction orthogonal to an axial direction of the nozzles; an electromotive actuator for swivelably driving the annular movable member; and a link arm for linking a distal side of each spraying nozzle to a corresponding circumferential position on the annular movable member in an angularly displaceable manner, wherein the spraying direction of each nozzle is displaced simultaneously by the electromotive actuator.