| 摘要 |
A controlled orifice for a hydraulic pressure control valve has a plunger and a conic orifice seat. The plunger has a head which forms a stagnation zone, and a rim with surfaces that define a sharp edge, these surfaces making an angle of at least 30 degrees with the conic bore orifice seat. A conic back surface extends to the plunger stem. The sharp edge of the rim forms a small annular vena contracta so that the regions where rapid flow is experienced are kept as small as possible. This reduces undesirable Bernoulli forces. |
