摘要 |
A control plate for effecting superior shut-off in a proportional control valve comprises a moveable disk-shaped element that has a flat surface, generally perpendicular to the valve axis of symmetry when closed, and translates toward or away from an orifice surrounded by a narrow lip or orifice ridge. Enhanced leak tightness in the valve shut-off condition is achieved by selectively incorporating into the control plate materials that are softer than the material comprising the orifice ridge. |