On Wednesday, February 22, 2017 at 12:50:18 AM UTC-5, Steve Kraus wrote:
I'm not familiar with the term "cartridge motor."

http://image2.cccme.org.cn/i_supply/...0000920290.jpg

This is a cartridge motor with the gear-train included. They come in many variation, including a double-layer device for additional torque. They are usually about 40mm across, but can be smaller/larger.

Peter Wieck
Melrose Park, PA