Patent ID: 7641563
Filing Date: 2010-01-05
Classification: F16D

Abstract:
1. A boot for constant-velocity universal joint, the boot comprising: a major-diameter fastener to be fitted around a major-diameter retainer; a minor-diameter fastener disposed separately away from the major-diameter fastener and coaxially therewith, having a minor diameter, which is smaller than that of the major-diameter fastener, and to be fitted around a minor-diameter retainer; and a bellows connecting the major-diameter fastener with the minor-diameter fastener integrally, and formed as a truncated cone shape substantially; the boot further exhibiting a dimension between the major-diameter fastener and the minor-diameter fastener, wherein the dimension is a distance between a major-diameter side fastening position for the major-diameter retainer and a minor-diameter side fastening position for the minor-diameter retainer; wherein: the bellows comprises a first root, a first crest, a second root, a second crest, a third root, a third crest, a fourth root, a fourth crest, a fifth root and a fifth crest, which are disposed in this order in the direction away from the major-diameter fastener to the minor-diameter fastener, and the first crest, the second crest, the third crest, the fourth crest and the fifth crest have a top, respectively, the tops of the second crest, third crest and fourth crest are disposed on an outer peripheral side with respect to a first line (L the bellows is reduced in size diametrically from large to small in the direction away from the first crest to the fifth crest sequentially; the first root, the second root, the third root, the fourth root and the fifth root of the bellows have a bottom, respectively; the bellows comprises the second root and third root whose bottoms are disposed on an inner peripheral side with respect to a second line (L the bellows is reduced in size diametrically from large to small in the direction away from the first root to the fifth root sequentially; and the bellows comprises the fourth root whose bottom is disposed on an outer peripheral side with respect to the second line (L