Some cone CVT styles use two rollers.[23][24] In 1903, William Evans and Paul Knauf applied to get a patent on a continually variable transmission working with two parallel conical rollers pointing in reverse Instructions and connected by belts which could be slid along the cones to fluctuate the transmission ratio. https://gearboxcvt93680.blogolize.com/not-known-factual-statements-about-gearbox-cvt-71825020