Micro Gear Motor Eccentric Shaft Adapter

thingiverse

If you need to add some wobble to a micro gear motor, this is the part for you! Use it as a button-pusher, switch-flipper, trigger-puller, belt tensioner, or whatever other small lateral motions you might need to create with a rotary motor. The STL file is set for a 12mm cam with a 5mm (+/- 2.5mm) stroke, but this can be easily changed in the SCAD file to whatever you want. If you don't already have motors, my favorite version is the Pololu Micro Gear Motors (https://www.pololu.com/category/60/micro-metal-gearmotors), which come with carbon brushes and a range of gear ratio options from 5:1 up to 1000:1. Pololu makes a double-shaft version that is perfect for adding an encoder on the back. For most applications where you use a cam, you will probably also want an encoder, but if not, here are a few single-shaft Pololu motors available on Amazon: 6V, 75:1 - http://amzn.to/1VOzb0w; 6V, 100:1 - http://amzn.to/1NnaXrn; 6V, 298:1 - http://amzn.to/1UIH7PB; 6V 1000:1- http://amzn.to/1Oixkt7. Alternatively, if you don't want to spend $15-$20 per motor, here are a few other manufacturers making similar motors at a lower cost, but I can't vouch for the reliability or quality. If you use these (or have other recommendations), please let me know how they work out for you: 6V, 300RPM - http://amzn.to/1Zs7NUe; 12V, 100RPM - http://amzn.to/1VOyZhM; 6V, 30RPM - http://amzn.to/1Oix8dn