Recoating device and 3D printer including the same

A powder-based 3D printer including;

• a build plate movable in a vertical direction and on which metal or non-metal powder is solidified and stacked;
• a recoating device applying powder on the build plate;
• a transfer device transferring the recoating device;
• a powder supply device supplying powder to the recoating device;
• and
• a laser scanning unit or a binder jetting unit to bond the applied powder,
• wherein
• the recoating device includes an ejector ejecting powder and a leveler leveling the ejected powder,
• the leveler includes a leveling blade formed to be adjacent to an ejection port of the ejector and leveling the ejected powder,
• where a direction parallel to a proceed direction of the recoating device is referred to as a front-to-rear direction, with the proceed direction being the front and the opposite direction being the rear;
• a direction in which the leveling blade extends is referred to as a left-to-right direction;
• and a height direction perpendicular to the front-to-rear and left-to-right directions is referred to as a up-to-down direction,
• the leveling blade,
• when connecting outermost corners of the leveling blade, a three-dimensional shape with a front and a back is formed, wherein a portion of the front of said three-dimensional shape is recessed toward the back to form an indentation space, and an inclined surface is formed at a front lower end of the leveling blade by said indentation space,
• the indentation space is defined by an indentation depth (d), which is the depth of the indentation space from the front in the front-to-rear direction;
• a space height (h), which is a distance in the up-to-down direction from a bottom surface of the leveling blade to an upper edge of a front opening of the indentation space;
• and an entry angle (φ), which is the angle of inclination between the inclined surface and the bottom surface of the leveling blade;
• wherein at least one of the indentation depth (d), the space height (h), and the entry angle (φ) is configured to vary depending on a position of the leveling blade in the left-to-right direction, and
• wherein the leveling blade generates a flow of powder in a direction perpendicular to a movement direction of the recoating device.