Tripod type constant velocity universal joint

A tripod type constant velocity universal joint comprising:

• an outer joint member in which track grooves extending in an axial direction are formed at three locations in a circumferential direction;
• a tripod member which has three leg shafts projecting in a radial direction;
• and
• a roller unit rotatably supported by each of the leg shafts and accommodated in each of the track grooves,
• the roller unit including
• a roller, and
• an inner ring that is externally fitted to the leg shaft and rotatably supports the roller,
• the inner ring having an inner peripheral surface formed as a convex curved surface in which an intermediate portion in an axial line direction of the inner ring projects toward an inner diameter side,
• the inner peripheral surface of the inner ring coming into contact with an outer peripheral surface of the leg shaft in a direction orthogonal to a joint axial line and forming a gap against the outer peripheral surface of the leg shaft in a direction of the joint axial line,
• wherein
• a projection is provided in regions including both end portions in a direction orthogonal to the joint axial line on a shaft end side with respect to the inner ring on the outer peripheral surface of the leg shaft, and
• a ratio T/ag1 between a dimension T of the projection in the direction of the joint axial line and a dimension ag1 of the outer peripheral surface of the leg shaft in the direction orthogonal to the joint axial line is 0.3 or more.