Almost every cordless drill features a fan for forced airflow, so why not also seek the same benefits with off-the-shelf components?
The pictures show fans printed in flexible TPU mounted to the outrunner rotor of the NEO Vortex and NEO 550 motors. The flexible filament doubles as a rubber isolator to protect the motor from impacts when on the field and while assembling.
The forced airflow over the motors prevents the below issues related to overheating the brushless motors:
Demagnetization of the rotor’s permanent magnets
Melting of the stator winding’s wire insulation
Reduced magnetic flux
Torque derates
Overall lower efficiency
STL files and a link to the configurable Onshape document are found here: Printables
Neat idea! Have you done any testing running a motor under the same conditions with and without the fan to see what difference it makes in motor temperature?
We are low on inventory of our most power dense motors (Neo 550 and Vortex) and are worried about running tests that might overheat them before our competitions this year (for the risks listed in the original post). If your team decides to print any, I’d love to see data around how much longer you can maintain peak motor performance and efficiency.
Here’s some test data from REV regarding the NEO 550 performance limitations. Their testing was done at stall, but hopefully real load cases include more time with the motor spinning (so a fan can help cool the motor). If I’m interpreting their data correctly, the NEO 550 can only support approximately 27 seconds of a 40A load before the motor overheats and fails.
