Powder feeding apparatus and method thereof

A powder feeding apparatus comprising;

• a tank which stores powder;
• a bottom board disposed on a bottom of the tank
• provided with through holes into which the powder passes through;
• an oblique section formed on a lower side of the through holes of a bottom board, such that an outer radius directed towards a lower side from a bottom plate-side gradually increases;
• a plate having a flat surface portion extending along an outer periphery of a lower-end portion of the oblique portion, and a groove portion inverted to a lower part from the flat surface portion, the plate receiving powder which drops along an outer wall of the oblique portion;
• a scraper relatively movable in relation to the plate, moving powder which has accumulated on top of the flat portion and the groove to a higher level than a constant level, the scraper moving the powder to an outer side of the flat surface portion, and uniformly smoothing a height of the powder accumulated on the flat surface portion and the groove portion to a constant height;
• and
• an ejector provided with a suction opening positioned at a front-side of the scraper, in a relative moving direction of the plate, in relation to the scraper, and a discharge opening discharging powder taken in from the suction opening, wherein the suction opening takes in powder which has accumulated on the groove portion of the plate;
• and the ejector is moveable relative to the scraper and the plate.