Patent ID: 6814907
Filing Date: 2004-11-09
Classification: B29C,B33Y,G05B

Abstract:
In an extrusion apparatus having an extrusion head including a liquifier which receives a solid element of a modeling material, heats the modeling material, and outputs a flow of the modeling material at an output flow rate while the extrusion head moves along a predetermined tool path at an extrusion head velocity, the apparatus using a material advance mechanism to supply the solid element of modeling material to the liquifier at an input rate which controls the output flow rate, a method for controlling the output flow rate comprising:determining an extrusion head velocity profile based on the tool path; and controlling the input rate of modeling material to the liquifier to produce an output flow rate of modeling material from the liquifier that is proportional to a current extrusion head velocity corresponding to the extrusion head velocity profile.