LSAM > Print Heads
The PH50 Print Head can print at rates up to 500 Lbs/Hr
LSAM machines use new, Thermwood developed, “PH Series” print heads. Advantages of this new design include much tighter control of print bead size, the ability to change bead dimensions while printing, the ability to print at high output rates without surging problems, better fusion between printed layers and a more void free printed structure.
This unique print head design incorporates three servo drives, but unlike the servo drives that operate the machine, they are not programmable machine axes.
Thermwood’s new design uses a servo controlled plastic extruder with a specially designed plasticating screw to heat and soften the composite thermoplastic material. It then uses a servo controlled fixed displacement polymer pump to deliver the softened material at a highly controlled rate to the print nozzle. This dual servo, two-step approach to generating the print bead eliminates a variety of problems encountered when trying to use an extruder alone to print. It allows much faster print rates without extruder surging, a common problem when operating extruders at high output rates.
Once the bead has been applied, a unique servo controlled compression wheel flattens and fuses each new printed layer to existing layers. Orienting this wheel with the print nozzle is the third servo drive in the PH series print head. It automatically tracks machine motion, following directly behind the print nozzle, regardless of what direction it moves.
Since it tends to squeeze out air that might otherwise be trapped between layers, this compression wheel results in superior bonding between printed layers and a better, void free structure.