Friction-disk transmissions had been used in quite a few vehicles and tiny locomotives inbuilt the early 20th century, including the Lambert and Metz automobiles. Used today in snow blowers, these transmissions consist of an output disk which is moved across the area in the input disk on which it rolls. https://gearboxcvt75476.get-blogging.com/33216552/the-basic-principles-of-gearbox-cvt