Multiplexed Extrusion System Development

Invention Reference Number

202305411

As additive manufacturing technologies advance and 3D-printers get larger, there is a constant need for larger extruders with higher throughput to construct larger objects at reasonable time. Extruders can continually be made larger, but their weight requires stiffer and more expensive gantry systems or robots to carry and control them. Larger extruders also suffer from unreliable flow control at low speeds (<10% of maximum throughput) which can be an issue for small builds and low speed printing operations. This technology uses multiple smaller extruders combined to multiplex the output into a single stream of molten polymer. While multiplexing helps improve the throughput without causing huge weight penalties, the use of smaller and less expensive extruders allows for easier flow rate control on small print jobs, as well as multi-material printability.

Description

Multiplexed extrusion combines more than one extruder to achieve combined throughput with minimal weight penalty, but without the unreliability of larger extruders at relatively low speeds in additive manufacturing. This technology uses multiple extruders combined to multiplex the output into a single stream of molten polymer. Using a single nozzle for two identical extruders can double output. If the desired print is too small, one extruder can be turned off so that only one of the extruders is used for printing more reliably at lower speeds compared to a larger extruder. This can be extended to more than just two extrusion systems, as well. Additionally, multiplexing can enable the use of multiple materials at once, by using each extruder for a different material. This can enable much more complicated bead designs such as “ribbon” and “core and sheath” and microstructure control. Multi-material extrusion in the same bead opens up new window of opportunities and application areas for additive manufacturing.

Benefits

Better flow rate control at a wider range of speeds
Increased throughput without additional weight penalties, even with weight savings
Improved microstructure, porosity
Multi-material extrusion capability in a single bead with unique properties and process benefits