Consider two "friction" wheels - a Pinion driving a Gear through contact of their outer diameters. The speed ratio is
Consider two "friction" wheels - a Pinion driving a Gear through contact of their outer diameters. The speed ratio is
![Development of knowledge based parametric CAD modeling system for spur gear: An approach - ScienceDirect Development of knowledge based parametric CAD modeling system for spur gear: An approach - ScienceDirect](https://ars.els-cdn.com/content/image/1-s2.0-S1110016818301108-gr1.jpg)
Development of knowledge based parametric CAD modeling system for spur gear: An approach - ScienceDirect
![design - Involute gear curve when root diameter falls below base diameter - Engineering Stack Exchange design - Involute gear curve when root diameter falls below base diameter - Engineering Stack Exchange](https://i.stack.imgur.com/ueewg.png)