Constant velocity universal joint

摘要

A constant velocity universal unit includes an outer joint member whose inner peripheral face is formed with three guide grooves, an inner joint member including three tripod shafts each formed with a tripod spherical face, three roller units each including an outer peripheral face and an inner peripheral face coaxially formed with each other. The guide groove includes a pair of strip-shaped inner side faces formed with a pair of guide projections having a substantially half arc shape in cross section whose diameter is smaller than a height of the inner side face of the guide groove. The constant velocity universal joint further includes an annular recess formed on a substantially center portion in a height direction of the outer peripheral face of the roller unit and engaging with the pair of guide projections in a rolling manner and rotatable relative to a central axis of the guide projection.