Editing Continuously variable transmission (section)

=== Cone ===
[[File:Evans friction cone - Hagley Aug 2009.jpg|thumb|Evans Variable Speed Countershaft]]

A cone CVT varies the drive ratio by moving a wheel or belt along the axis of one or more conical rollers. The simplest type of cone CVT, the single-cone version, uses a wheel that moves along the slope of the cone, creating variation between the narrow and wide diameters of the cone.

Some cone CVT designs use two rollers.<ref>{{cite web|url=https://www.youtube.com/watch?v=MhFK5gfAGpM| archive-url=https://ghostarchive.org/varchive/youtube/20211107/MhFK5gfAGpM| archive-date=2021-11-07 | url-status=live|title=CVT Explained | date=February 2008|via=YouTube |access-date=27 August 2011}}{{cbignore}}</ref><ref>{{cite web|url=https://www.youtube.com/watch?v=pyYNvwKPAKA| archive-url=https://ghostarchive.org/varchive/youtube/20211107/pyYNvwKPAKA| archive-date=2021-11-07 | url-status=live|title=CVT transmission | date=23 November 2007|via=YouTube |access-date=27 August 2011}}{{cbignore}}</ref> In 1903, William Evans and Paul Knauf applied for a patent on a continuously variable transmission using two parallel conical rollers pointing in opposite directions and connected by belts that could be slid along the cones to vary the transmission ratio.<ref>William Evans and Paul Knauf, Variable-Speed-Transmission Device, {{US Patent|759872|U.S. Patent 759872}}, granted 17 May 1904.</ref><ref>William Evans and Paul Knauf, Power-Transmission Device, {{US Patent|759873|U.S. Patent 759873}}, granted 17 May 1904.</ref> The Evans Variable Speed Countershaft, produced in the 1920s, is simpler—the two rollers are arranged with a small constant-width gap between them, and the position of a leather cord that runs between the rollers determines the transmission ratio.<ref>{{cite journal |title=Evans Friction Cone Co. advertisement |journal=Machinery Magazine |date=19 January 1922 |url=http://antiquemachinery.com/yahoo_site_admin/assets/docs/000-Machinery-Magizine-January-19-1922-Gorton-Panagrph-600dpi--top-.361154958.jpg |access-date=18 July 2020}}</ref>