| 摘要 |
<p>A method of manufacturing a ball joint and a housing therefor, comprising the steps of forming an intermediate formed body (41), having a cylindrical arm-equivalent part (42) installed projectedly thereon with a formed hole (42a) larger in inner diameter than a connecting projected part (20) of an arm part (15), on the outer peripheral surface of a cylindrical body part (13), inserting a tap (44), having a male thread (43) on the outer peripheral surface thereof, into the formed hole (42a) in the arm-equivalent part (42), forming a female thread (19) on the inner peripheral surface of the formed hole (42a) in the arm-equivalent part (42) by pressing, to reduce a diameter, the formed body between opposed recessed surface parts (49, 49) of an upper mold (47) and a lower mold (48) in a semi-cylindrical recessed shape corresponding to the outer peripheral surface of the connected projected part (20), and forming the arm part (15) by extracting the tap (44) while the tap is rotated, whereby the female thread can be formed more easily, in a shorter time than when the female thread is formed by the male thread (43) of the tap (44).</p> |
