| 摘要 |
<p>[PROBLEMS] A method of producing a ball joint, in which, in reducing of the diameter of a wall of a socket in production of the ball joint, parting lines and wrinkles are not produced on the outer surface of the socket and which appropriately controls a clearance between the socket and a ball section. [MEANS FOR SOLVING PROBLEMS] A first member (12) having a ball section (14) of a ball joint (10) and a second member (15) having a socket (16) are supported with the ball section (14) received in the socket (16). A pair of dies (20, 30) holds, from the radially outside, the wall (18) surrounding an opening (17) of the socket (16) and intermittently presses the wall (18) radially inward by gradually approaching the wall while performing quick vibration of repeated approach and retract motions. At each interval of the intermittent pressing operation, a support and rotation device (40) rotates the socket (16)(second member (15)) by a small distance about the center axis (C2) of the socket (16). Thus, the dies (20, 30) sequentially press a large number of points on the entire circumference on the outer surface of the wall (18) of the socket (16), and as a result, the wall (18) is bent inward to reduce its diameter.</p> |
