Patent ID: 9579851
Date: 2017-02-28
CPC Classifications: B29C,B33Y

Claim:
1. A three-dimensional printer for additive manufacturing of a part, the three dimensional printer comprising: a fiber composite filament supply of unmelted fiber reinforced composite filament including one or more inelastic axial fiber strands extending within a matrix material of the filament; a movable build platen for supporting the part; a print head opposing the build platen and including a composite filament ironing tip and a heater that heats the composite filament ironing tip above a melting temperature of the matrix material; a plurality of actuators that move the print head and the build platen relative to one another in three degrees of freedom; a filament drive that drives the unmelted fiber reinforced composite filament, and the inelastic fiber strands embedded within, into the print head at a linear feed rate; a cold feed zone positioned between the filament drive and the ironing tip, maintained below a melting temperature of the matrix material; and a controller operatively connected to the heater, the filament drive and the plurality of actuators, wherein the controller executes instructions which cause the filament drive to hold an unattached terminal end of the composite filament in the cold feed zone between the filament drive and the ironing tip.