Material filling apparatus for 3D printing

A material filling apparatus for 3D printing, capable of filling a material into a material tank through a feeding part of a feeding machine, and the material tank having a front end and a rear end, and the material filling apparatus comprising:

• a fixed sleeve, having a fixed end connected to the feeding part and a first open end opposite to the fixed end;
• a moving sleeve, movably inserted and tightly fitted into and interfered with the fixed sleeve, and having a second open end corresponsive to the fixed end and a blocking end corresponsive to the first open end;
• and a material output pipe, inserted into the moving sleeve, and having a connecting end connected to the feeding part and a material output end opposite to the connecting end, and the material tank being movable sheathed on the exterior of the material output pipe, and the rear end of the material tank and the material output end being movably situated opposite to one another, and the blocking end of the moving sleeve blocking the rear end of the material tank;
• wherein, the material tank is squeezed by the filling material of the feeding machine to move in a direction from the connecting end towards the material output end, and the rear end of the material tank moves away from the material output end of the material output pipe and pushes the blocking end of the moving sleeve, so that the moving sleeve moves together with the material tank with respect to the fixed sleeve.