CONSTANT VELOCITY JOINT

PROBLEM TO BE SOLVED: To provide a constant velocity joint capable of improving an assembly workability of a resin boot to an outer circumferential surface of an outer ring and also improving sealability.SOLUTION: This invention comprises an outer ring 20 in which three raceway grooves 21 extending in an axial direction are formed at an inner circumferential surface and three outer circumferential grooves 22 extending in a circumferential direction at an outer circumferential surface are provided; a boot 5 having a large diameter fixing part 6 fitted to an end part outer circumferential surface 29 at one side in the axial direction of the outer ring 20 and molded by resin material; and a large diameter clamp member 41 for fastening the outer circumferential surface 62 of the large diameter fixing part 6. The large diameter fixing part 6 is constituted in such a way that its outer circumferential surface 62 is formed into a circular outer circumferential shape, thick parts 7 and thin parts 8 are alternately arranged in the circumferential direction in compliance with an outer circumferential shape of the outer ring 20, its diameter is gradually expanded toward an axial outward direction, the central part of the outer circumferential surface 62 of each of the thick parts 7 is provided with one V-groove 71 in which a radial sectional shape is substantially V and both two end locations of the inner circumferential surface 61 are provided with V-grooves 71 in which a radial sectional shape is substantially V, and the V-grooves 71 are formed to have a groove depth in which it is gradually shallow from the axial end part to the inside part. 【課題】外輪外周面への樹脂製ブーツの組み付け作業性を向上させるとともに、シール性を向上させることができる等速ジョイントを提供する。【解決手段】内周面に軸方向に延びる３本の軌道溝２１を形成し、外周面の周方向に３本の外周溝２２を有する外輪２０と、外輪２０の軸方向の一方側の端部外周面２９に嵌合する大径取付部６を有し、樹脂材料により成形されるブーツ５と、大径取付部６の外周面６２を締め付ける大径クランプ部材４１と、を備え、大径取付部６は、外周面６２が円形の外周形状に形成され、外輪２０の外周形状に合わせて周方向に厚肉部７と薄肉部８とが交互に配置され、軸方向外方へ向かって漸次拡径してなり、各厚肉部７の外周面６２の中央に１箇所、内周面６１の両端の２箇所に、径方向断面形状が略Ｖ字形のＶ溝７１を設け、Ｖ溝７１は溝の深さを軸方向の端部から内方へ向かって漸次浅くして形成されている。【選択図】図３