Patent ID: 6880773

Claim:
A shut device for a discharge outlet in a grinder located on a bottom of the grinder comprising: a stationary part having first and second curved walls located on opposing sides thereof and each of the first and second curved walls has a tenon protruding inwardly on an interior surface; and a rotary part being a step-shaped cap with an abrupt fitting ring corresponding to the first and second curved walls so as to fit with the first and second curve walls such that a top of the fitting ring contacts with a discharge outlet at a circumference thereof, having an annular surface with two L-shaped guide grooves corresponding to the two tenons so that the tenons are inserted into the guide grooves to form an engagement respectively, having a plurality of hollow openings and stop plates being alternately positioned at a center thereof to correspond with three locating points of opening, shutting and detaching from the discharge outlets and three positioning projections being provided on the guide grooves in accordance with the three locating points; whereby, once the rotary part is turned, the tenons move along the guide grooves and engage with the locating points one at a time respectively such that the hollow openings align with the discharge outlet for ground powder falling down or the stop plates close the discharge outlet preventing the powder from falling down.