Patent ID: 7435181

Claim:
A constant velocity ratio universal joint of the tripot type comprising: an outer joint member having a rotational axis and three guide grooves extending parallel to its rotational axis and equally circumferentially spaced thereabout, each guide groove having opposed side portions; an inner joint member disposed inside the outer member, having a rotational axis and three arms equally spaced about this rotational axis and extending radially into the guide grooves of the outer joint member; and each arm carrying a roller having a thickness and an external surface which engages said opposed side portions of the guide groove into which the aim extends so that the roller is constrained to roll therealong; wherein the cross-sectional shape of said external surface of each roller is of an arcuate shape, and the cross-sectional shape of each guide groove side portion is different from said arcuate shape of the roller external surface, said roller external surface and each guide groove side portion having angular contact engagement with one another at two spaced points which lie in said roller external surface and guide groove side portion, and wherein a radius of said arcuate shape of said external surface is equal to or less than one half of said thickness of said roller.