Thermal melting three-dimensional printer and method for producing molded object

A thermal melting three-dimensional printer comprising:

• an extruder;
• and
• a push-in mechanism, wherein the extruder includes a hopper, a cylinder, and a nozzle,
• the hopper is configured to feed pellets into the cylinder through a raw material feed port provided in the cylinder,
• the extruder is configured to melt and knead, in the cylinder, the pellets fed into the cylinder to form a molten resin and to extrude the molten resin through the nozzle to form a strand,
• the push-in mechanism is configured to push pellets loaded on a loading surface of the hopper into the cylinder through the raw material feed port,
• the push-in mechanism includes a rod in contact with the pellet, and a driving mechanism that drives the rod,
• the rod is driven such that a tip of the rod presses the pellets in a direction of the raw material feed port,
• the rod includes a soft portion,
• the rod is driven such that the tip of the rod moves in the direction of the raw material feed port in a state where the rod is pressed against the loading surface to be curved at the soft portion, and
• a motion in a vertical direction of a root of the rod is converted into a motion of the tip of the rod approaching or moving away from the raw material feed port.