| 摘要 |
<p>A valve actuator for use in a pressure regulator. It comprises an electromagnet (10) having a plurality of pole pieces (10a, 10b, 10c). A valve actuating permanent magnet (12) is moveably secured to one (10c) of the pole pieces. The pole pieces are so disposed relative to each other that four distinct magnetic forces combine to urge the permanent magnet in a first or second direction depending on the polarity of current applied to a coil disposed about one of said pole pieces.</p> |
