Patent ID: 7510344

Claim:
A joint structure comprising: an arm having upper and lower surfaces; a ball joint including a ball stud having a spherical ball part and a shank part extending from the spherical ball part; a bearing cupping the spherical ball part of the ball stud; a housing holding the bearing therein; and press-fitting means for weakening a load by the arm after the housing is pressed into a hole of the arm; and wherein the press-fitting means is defined by two circumferential grooves in an outer-circumference surface of the housing of the ball joint and an outer diameter of the housing extending between the two grooves formed to be smaller than an inner diameter of the hole of the arm in such a manner that a gap is formed therebetween; the housing of the ball joint is adapted to be pressed into the hole of the arm; and the grooves and gap are located in a region between the upper and lower surfaces of the arm to inhibit pressure to the spherical ball part of the ball stud by reducing the sliding friction force on the ball stud.