Active Cooling & Heating - A Brain-trust Engineering Project

The idea has been brought to attention to attempt to design a system wherein we would have the ability for active heating of the build chamber and active cooling for PLA.

The system as currently discussed would be comprised of an outside chamber containing a small bank of peltier chips. The main chamber would be divided in two by the chips to provide a cooling chamber and a heating chamber.

From there we would have fans to pull air in and across finned heat sinks, for both hot and cold air, and exit fans to push the air where it needed to go.

Some of the purposes and ideas for this have been:

• Remove the fan from the X-Carriage all together and run a vent tube to the nozzle in its place to provide chilled air for PLA setting or heated air for ABS temperature assistance.

• Running a cold air vent tube to the heat sink of all metal hot ends.

• Run heated/chilled air lines into the system for use with the enclosure system to provide ambient temperature regulation & assistance.

• Active stepper cooling.

• Lines to assist with heating the bed to remove load from the heating element.

Optimally, air intake fans would be reversible to vent the unneeded air depending on if hot/cold air is desired for the print or a separate vent fan that can be opened and activated.

We could also design the intended exit nozzles to funnel and evenly disperse the air through a number of tubes to reach the necessary areas.

The chamber and funnel could likely all be 3D printed as the peltier chips wouldn't need to be run at a temp high/low enough to damage the plastic.


If anyone else involved in the discussion remembers anything I've missed, please add it to the thread.

Everyone else, feel free to chime in with ideas and/or designs and lets see if we can make this happen.

**If you're thinking peltier chips are too expensive. . . Think again, they've come down in price substantially.

 

http://www.adafruit.com/products/1330

What sort of efficiency are you looking to achieve?

 

I'm believe they have improved since then. Last time I was really working with them was back in 2001 or so.

I'm pretty sure the efficiency has improved since then, but if nothing else it's also a matter of the efficiency curve on them. At higher currents (more drastic temp change) they become less efficient than at a lower difference. If we were to go with a 12V 6A(Max) chip and only run it at 1A or 2A for a lower temp change we should be able to maintain efficiency relatively well.

We wouldn't need a huge change in air temp for this, just an offset of the ambient temp to assist in processes.

 

And the one Mike linked has a temp difference from Ambient of 66C at the max 5A.

So even 2A would still stay in the relatively efficient range and still provide a good temp adjustment.