| abstract |
(57) [Summary] [Objective] To provide a high-density ball head with a highly reliable, long-life, and inexpensive spring pin for a socket. [Structure] The main body 11 is made of a phosphor bronze pipe, and the inner surface of the main body 11 has a tapered end and the contact portion 1 is formed. 2 and the angle of the inner surface of the taper with respect to the axis of the main body θ 1 Is about 30 degrees. Four splits 13 are formed in the contact portion along the axis from the tip end, and elastically contact the ball head 15 by the elasticity of the divided linear portions. Even if the spring pin is pushed in, the contact point 21 with the contact portion 12 of the ball head 15 becomes substantially constant. |