Dust cover for ball joint

A dust cover for a ball joint comprising:

• a spherical head portion formed in one end of a ball stud, the spherical head portion being retained within a socket;
• a shaft in the other end of said ball stud, the shaft being fastened and fixed to a knuckle;
• a one end large-diameter opening portion being fixed and retained to an outer peripheral surface of said socket;
• the other end small-diameter opening portion constructed by a tube portion which is fitted and fixed onto an outer peripheral surface of said shaft, and an outward flange portion which extends outward in a diametrical direction from an end portion in said socket side of said tube portion, the other end small-diameter opening portion in which a reinforcing ring made of a hard material is integrally formed;
• and
• the dust cover being retained onto a retainer which is formed into an L-shaped cross section and is made of a hard material,
• wherein said reinforcing ring is constructed by a cylindrical portion and an inward flange portion which extends toward an outer peripheral surface of said retainer from an end portion in said knuckle side of said cylindrical portion, and an end portion in said socket side of said cylindrical portion in said reinforcing ring comes into contact with the outward flange portion of said retainer and diametrically inner end portion Of said inward flange portion comes into contact with an outer peripheral surface of said tube portion.