Editing Constant-velocity joint (section)

=== Rzeppa joints ===
[[File:Cv joint large.png|right|thumb|Rzeppa joint]]
[[File:Gelenk-welle.jpg|thumb|left|Rzeppa joint (compared to a [[1 euro coin]])]]

A Rzeppa joint (invented by [[Alfred H. Rzeppa]] in 1926) consists of a spherical inner shell with 6 grooves in it and a similar enveloping outer shell. Each groove guides one [[Ball bearing|ball]]. The input shaft fits in the centre of a large, steel, star-shaped "gear" that nests inside a circular cage. The cage is spherical but with ends open, and it typically has six openings around the perimeter. This cage and gear fit into a grooved cup that has a splined and threaded shaft attached to it. Six large steel balls sit inside the cup grooves and fit into the cage openings, nestled in the grooves of the star gear. The output shaft on the cup then runs through the wheel bearing and is secured by the axle nut.

This joint can accommodate the large changes of angle when the front wheels are turned by the steering system; typical Rzeppa joints allow 45°–48° of articulation, while some can give 54°.<ref>{{cite web |last1=Hoshino |first1=Manabu |last2=Funahashi |first2=Masashi |title=NTN Technical Review No.75 (2007): Fixed Constant Velocity Joint with a Super High Operating Angle of 54 Degrees (TUJ) |url=http://www.ntn.co.jp/english/products/review/pdf/NTN_TR75_en_P016.pdf |website=www.ntnglobal.com |access-date=11 April 2021 |archive-url=https://web.archive.org/web/20190730143903/https://www.ntnglobal.com/en/products/review/pdf/NTN_TR75_en_P016.pdf |archive-date=2019-07-30}} (Also found in {{cite web |title=Automotive Environmental Technologies |url=https://www.ntnglobal.com/en/products/review/pdf/NTN_TR75_en.pdf |publisher=NTN |access-date=11 April 2021 |date=2007}})</ref> At the "outboard" end of the driveshaft a slightly different unit is used. The end of the driveshaft is [[Rotating spline|splined]] and fits into the outer "joint". It is typically held in place by a [[circlip]].