POWDER FEED OPENING FOR POWDER FLUIDIZING TANK

PROBLEM TO BE SOLVED: To prevent a powder from being violently stirred up and flowing out to the outside, when the fluidized powder in a fluidizing tank is consumed and the make-up powder is supplied to replenish the consumed quantity, so as to retain a pleasant working environment. SOLUTION: The powder feed inlet 2 is a cylindrical body provided with the cover face 21 protruded from the top face 11 of a hermetically sealed tank 1 to detachably fit the upper cover 23, and the bottom face 22 projecting to the inside. And a cone 3 with a conical body contained in the cylindrical body is fitted to form an inclined space E narrowed as it goes down between both cylindrical and conical bodies. A powder suction duct 4 wound up on the outer peripheral face 25 of the feed inlet on the top face 11 of the hermetically sealed tank is connected to the inside of the tank at one end 41 and connected to a duct collector 6 at the other end 42 so as to be freely opened or closed. On feeding the powder P, a large quantity of the powder is stirred up, but as the nearby position of the end 41 is always in a negative pressure through the powdery material-suction duct 4, the entrained air passing through the inclined space narrowed as it goes down is sucked while increasing the speed to prevent the stirring-up dust from flowing out to the outside.