Editing Coupling (section)

=== Oldham ===
{{Unreferenced section|date=July 2022}}
[[Image:Oldham coupler animated small.gif|thumb|Animated Oldham coupler]]
An ''Oldham coupling'' has three discs, one coupled to the input, one coupled to the output, and a middle disc that is joined to the first two by [[tongue and groove]].  The tongue and groove on one side is perpendicular to the tongue and groove on the other. The middle disc rotates around its center at the same speed as the input and output shafts.  Its center traces a circular orbit, twice per rotation, around the midpoint between input and output shafts. Often [[Spring (device)|spring]]s are used to reduce [[Backlash (engineering)|backlash]] of the mechanism. An advantage to this type of coupling, as compared to two universal joints, is its compact size. The coupler is named for [[John Oldham (engineer)|John Oldham]] who invented it in [[Ireland]], in 1821, to solve a problem in a [[paddle steamer]] design.

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Image:Klauenkupplung 1.jpg|Oldham coupler, assembled
Image:Klauenkupplung 3.jpg|Oldham coupler, disassembled
</gallery>