Powered Metal Variator Components

A variator having at least one roller which runs upon at least one race to transfer drive from one to the other at variable ratio, the variator further comprising a fluid supply for supplying fluid to the race and roller thereby to provide a fluid film by which the roller and the race are separated in use, the roller having a running surface with roughness Rq(roller) and the race having a roughness Rq(race), composite roughness being defined as

• √{square root over (Rq(race)2+Rq(roller)2)}{square root over (Rq(race)2+Rq(roller)2)}
• and the variator's specific film thickness being defined as the minimum thickness of the fluid film in normal operation divided by the composite roughness, the variator being characterised in that its specific film thickness is less than 1.0.