3D printer having dual stage structure

A 3D printer having a dual stage structure, the 3D printer comprising:

• an extrusion unit comprising a nozzle configured to extrude a raw material;
• a stacking base unit positioned under the extrusion unit and comprising a bed configured to receive the raw material on an upper surface thereof so that an object is formed in a layer-by-layer manner on the upper surface of the bed;
• and
• a cutting unit between the stacking base unit and the extrusion unit and comprising a cutting tool configured to grind or cut the object formed on the upper surface of the bed, and
• a frame positioned outside the extrusion unit, the cutting unit, and the stacking base unit,
• wherein a distance between the extrusion unit and the cutting unit and a distance between the cutting unit and the bed are variable relative to each other
• wherein the frame extends vertically and is configured to be connected to one or more of the extrusion unit, the cutting unit, and the bed, and
• the one or more of the extrusion unit, the cutting unit, and the stacking base unit are configured to be vertically movable along the frame,
• wherein the frame comprises:
• an outer frame comprising a plurality of outer guide beams arranged in a circular shape;
• and
• a rotatable frame comprising one or more rotatable guide beams arranged inside a circle formed by the outer guide beams,
• wherein the cutting unit is configured to be connected to an inner side of the rotatable frame,
• the rotatable guide beams are configured to extend vertically such that the cutting unit is vertically movable along the rotatable frame, and
• the rotatable frame is configured to be rotatable inside the outer frame around a center of the circle formed by the outer guide beams such that the cutting unit is rotatable about the center,
• wherein the rotatable frame further comprises a ring-shaped connection part configured to be connected to lower portions of the rotatable guide beams and to be concentric with the circle formed by the outer guide beams,
• the outer frame further comprises a cylindrical connection part configured to connect lower portions of the outer guide beams and to be inserted into the ring-shaped connection part, and
• the ring-shaped connection part is configured to be rotatable on the cylindrical connection part to rotate the rotatable frame.