The buzz today comes from a new MakerBot patent that claims an ability to change filament on the fly - within a single extruder.
USPTO patent application US 20140034214 A1 is titled, “Build material switching”. That’s exactly what is to happen. The MakerBot team seems to have created a simplified method of connecting two different filament feeds to a single extruder. The concept is to slide a platform of two filament feeds alternately across a hot end, as you can see in the diagram above.
Reading through the lengthy, verbose and vague patent language reveals they are not merely attempting to patent the mechanism in the image, but also much of the activity, including computation of precise filament lengths, evacuation of the hot end during “transitions” and so on. This builds on one of MakerBot’s previous patents that involved evacuation of a hot end for color changing.
Such a component could enable a 3D printer to print in two colors. We do not believe it is primarily intended to print different materials, however, as that would require the hot end to be constantly changing temperature, complicating filament evacuation and could dramatically slow down printing as seems to happen with many dual-extruder machines of today.
You must remember a few things:
- This is a patent application; it has not yet been approved
- Just because a patent appears, it doesn’t mean there is even a prototype in a lab, let alone a product
- There is no certainty whether this approach will practically work
But if it does work. Well. We could expect MakerBot to eventually develop and release a personal 3D printer that includes the magic color-changing extruder. More function with less hardware could mean a lower cost, higher performance option. Or perhaps simply more profitability for MakerBot.
Via Google Patents