Innovation and design

School of Engineering project engineer patents design for 3-D printer extruder heater

Project Engineer Ralph Stirling of the Walla Walla University School of Engineering, had a patent issued on one of his prototypes this last spring. The newly patented product is an inductively heated extruder heater, which is a heated nozzle for hot melt glue dispensers and desktop 3-D printers. The nozzle heats up 10 times faster than what most models are operating at now, with a quarter of the power normally needed.

Aside from the low-power features, Stirling was also able to include a safety feature to prevent the heater from getting too hot, since some 3-D printers have been known to overheat and catch fire. With his design, Stirling will automatically limit the temperature under a few common fault conditions. He applied for the patent in March 2013, and it was issued this spring.

They say necessity is the mother of invention, and that does not ring false for this story. In 2012, two WWU engineering students, Luke Chilson and Alex English, contacted the School of Engineering for help on a project. The two had started a business manufacturing and selling plastic filament for desktop 3-D printers, and they had a new idea for a compact folding 3-D printer. This hypothetical 3-D printer would fold up into the size of a laptop battery and be powered from a USB port. A group of WWU engineering and product design faculty met to brainstorm with Chilson and English on the idea. For Stirling, it became evident that to create a compact 3-D printer, they would have to reduce the size of the extruder assembly that melts the plastic. Stirling focused on developing a plan for a small, low-power heater, which eventually led to his patent.

Stirling is currently working with Chilson and English’s company, ProtoParadigm, to create a version of the product that will be ready for manufacture by the end of the year. He enjoyed designing, analyzing, fabricating prototypes, and programming controllers for this project and has also appreciated getting students involved in various aspects of the project.

While the process of seeing the patent application through the United States Patent and Trademark Office was at times cumbersome and slow, Stirling found it educational to go through all the steps himself, rather than turning the process over to a patent attorney. Stirling hopes his patent, “will lead to better desktop 3-D printers, higher quality prints, lower power consumption, and greater safety.” He also envisions his patent leading to more practical models of quick-heating, battery-powered hot melt glue guns.

Posted July 18, 2017

Professional portrait of Ralph Stirling.
Ralph Stirling, project engineer for the WWU School of Engineering, designed and patented an improved part for desktop 3-D printers.