CONSTANT-VELOCITY UNIVERSAL JOINT

PROBLEM TO BE SOLVED: To provide a constant-velocity universal joint optimum for a drive axle to be used under an environment, under which neither a resin boot nor a rubber boot can be used.SOLUTION: In a constant-velocity universal joint, the opening of an outside joint member is hermetically sealed with a metal spherical surface seal structure. The metal spherical surface seal structure comprises: a spherical surface seal inner ring having a convex spherical seal face; and a spherical surface seal outer ring having a concave spherical seal face for relatively coming into slide contact with the seal face of the spherical surface seal inner ring. The seal face of the spherical surface seal inner ring is constituted of the external diameter face of the open end side of the outer joint member. On the spherical surface seal inner ring, there is mounted a seal member to have a slide contact with the seal face of the spherical surface seal outer ring. There is provided angle regulation means for preventing dropout of a seal.SELECTED DRAWING: Figure 1 【課題】樹脂ブーツやゴムブーツを用いることができない環境下で使用されるドライブアクスルに最適な等速自在継手を提供する。【解決手段】外側継手部材の開口部が金属球面シール構造にて密封される等速自在継手である。金属球面シール構造は、凸球面状のシール面を有する球面シール内環と、この球面シール内環のシール面と相対的に摺接する凹球面状のシール面を有する球面シール外環とを備える。球面シール内環のシール面が外側継手部材の開口端側の外径面にて構成される。球面シール内環に、球面シール外環のシール面に摺接するシール部材を装着した。シール脱落防止のための角度規制手段を設けた。【選択図】図１