Spool valve and method for manufacturing the same

摘要

The present invention relates to a spool valve (5) having a plurality of small-diameter portions (8) formed at predetermined spacings on a peripheral surface of a shaft, and pairs of annular ridges (9) on peripheral surfaces of the small-diameter portions to have a larger diameter than an inner diameter of collars, the collars (4) being closely fitted between the annular ridges to make valve bodies, wherein the collars comprise an inner wall (4iw), an outer wall (4ow) and at least one connection (4c) therebetween, and an annular gap (3) is provided between the inner wall and the outer wall.