Some cone CVT types use two rollers.[23][24] In 1903, William Evans and Paul Knauf utilized for a patent on the consistently variable transmission making use of two parallel conical rollers pointing in reverse Instructions and related by belts that could be slid alongside the cones to range the transmission ratio. https://johnnyaludj.thelateblog.com/33237511/5-simple-techniques-for-gearbox-cvt