Nozzle module and three-dimensional printer

A three-dimensional printer, comprising the nozzle module which comprises:

• a heat dissipation assembly;
• a locking assembly, comprising a clamping ring fixed to the heat dissipation assembly and a rotary member connected to the clamping ring, wherein the clamping ring is provided with a clamping hole and an opening which penetrate through the clamping ring in a first direction, and the opening communicates with the clamping hole;
• and
• a nozzle assembly, passing through the clamping hole and the heat dissipation assembly in turn along the first direction, wherein
• the rotary member is able to rotate relative to the clamping ring, a width of the opening is selectively reduced or increased when the rotary member rotates relative to the clamping ring, thereby enabling the clamping ring to clamp or release the nozzle assembly.