| 摘要 |
A hydraulic valve includes a valve body having first and second ends, a bore extending therebetween, and first and second drain passages opening to the bore; a spool disposed in the bore and biased in a neutral position, the spool having first and second ends and first and second annuli axially spaced from the first and second ends respectively, whereby when the spool is in the neutral position, the first and second drain passages are connected to first and second bores respectively via the respective annulus, and wherein the spool is axially movable relative to the body by fluid acting on one of the ends to block fluid flow from the first and second bores to the first and second drain passages. |
