Abstract: A ball joint having a cylindrical housing containing a plurality of projections. A cylindrical ball seat is inserted within the housing and secured to the housing by the plurality of projections. A ball stud having a spherical head portion is rotatably disposed within the ball seat, and a cap is disposed at and secured to the lower, outside portion of the ball seat.

Abstract: A ball joint used for a steering arrangement or a suspension system of automobiles, comprises a housing having an inner side formed into a polygonal shape; a ball seat having an outer body surface formed as the same polygonal shape as formed in the housing; vertical flanges being formed at a closing portion of the ball seat and spaced apart at intervals corresponding to sides of the polygonal shape, each vertical flange having first and second fixing protrusions formed at an opening portion of the ball seat, and a hook protrusion having a groove formed at an inner surface of a lower portion of each vertical flange; and, a cap having a convex portion at a side and inserted in the vertical flanges so as to be fixed to the vertical flanges.