Extruder thermal management

Abstract

A variety of techniques are used to manage temperature in and around an extruder for a three-dimensional printer.

What is claimed is: 
     
         1 . A method of thermal management of an extruder of a three-dimensional printer, the method comprising:
 heating a chamber defined by a nozzle assembly of the extruder, the chamber extending from a first orifice to a second orifice;   moving a first fluid across the first orifice to form a thermal break mitigating an upward heat flow from the chamber toward the first orifice; and   directing ambient air from an ambient environment at an angle radially away from the second orifice via a manifold defining a plurality of exit holes positioned and oriented to provide an omnidirectional fluid flow outward about the second orifice, and to cool a region of deposited build material around a perimeter of the second orifice.   
     
     
         2 . The method of  claim 1 , wherein a first thermal conductivity between a heating element and the chamber is greater than a second thermal conductivity between the heating element and the plurality of exit holes defined by the manifold. 
     
     
         3 . The method of  claim 1 , wherein heating the chamber includes maintaining a build material in the chamber at a target temperature above a liquefaction temperature of the build material, wherein the first fluid moves across the first orifice at a first temperature below the target temperature of the build material in the chamber, and wherein the omnidirectional fluid flow of ambient air from the manifold moves about the perimeter of the second orifice at a second temperature below the target temperature of the build material. 
     
     
         4 . The method of  claim 1 , further comprising adjusting a volumetric flow rate of the first fluid across the first orifice based on a temperature of the nozzle assembly. 
     
     
         5 . The method of  claim 1 , further comprising adjusting a volumetric flow rate of ambient air from the manifold based on movement of the extruder. 
     
     
         6 . The method of  claim 1 , wherein providing the omnidirectional fluid flow about the second orifice includes directing multiple streams of ambient air about the perimeter of the second orifice. 
     
     
         7 . The method of  claim 1 , wherein movement of the first fluid across the first orifice is independently controllable relative to movement of ambient air about the perimeter of the second orifice. 
     
     
         8 . The method of  claim 1 , wherein the first fluid is provided via a first fluid source. 
     
     
         9 . The method of  claim 8 , wherein the ambient air is provided by a second fluid source independent from the first fluid source. 
     
     
         10 . The method of  claim 9 , wherein one or more of the first fluid source and the second fluid source include a variable-speed fan. 
     
     
         11 . The method of  claim 1 , wherein the first fluid and the ambient air are provided via a single fluid source. 
     
     
         12 . The method of  claim 11 , wherein the single fluid source includes a variable-speed fan. 
     
     
         13 . The method of  claim 1 , wherein the manifold is fluidically isolated from the chamber defined by the nozzle assembly. 
     
     
         14 . The method of  claim 1 , wherein exit holes of the plurality of exit holes are spaced equidistant from one another about the perimeter of the second orifice. 
     
     
         15 . The method of  claim 1 , wherein a surface of the nozzle assembly is tapered between a position of the plurality of exit holes and the second orifice. 
     
     
         16 . The method of  claim 1 , wherein the ambient environment includes a build volume of the three-dimensional printer. 
     
     
         17 . The method of  claim 1 , wherein the ambient environment includes a source external to a build volume of the three-dimensional printer. 
     
     
         18 . The method of  claim 1 , wherein the ambient environment includes a tank of air. 
     
     
         19 . The method of  claim 1 , further comprising adjusting an exit hole of the plurality of exit holes. 
     
     
         20 . The method of  claim 19 , wherein adjusting the exit hole includes at least one of: opening the exit hole, closing the exit hole, and adjusting a direction of fluid flow from the exit hole.