Fremgangsmåde til fremstilling af en spoleventil

摘要

Disclosed are a spool valve which comprises: a shaft (1) having plural small diameter portions (2) formed at required intervals on the circumferential surface of the shaft; a pair of circular convex portions (3) having a diameter larger than the inner diameter of a collar (4), provided on the outer circumferential faces of each small diameter portion; and the collar (4) subjected to quenching processing, arranged between the circular convex portions (3) so that the side faces of the circular convex portions are in close contact with circular concave portions (6) formed at both ends of a center hole of the collar (4) or both side faces themselves of the collar (4), and a process for manufacturing the same.