| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve the reproducibility of valve opening and closing by opening and closing the valve actively. SOLUTION: For a valve opening operation, a coil 52 is energized to induce a magnetic field wherein a permanent magnet 44a, or resultantly an operating part 44, is repulsed away from an iron core 50, as a result of which the operating part 44 is moved toward a ball 28 and a pin 44b pushes the ball 28, together with a deadweight 32, away from a valve seat 30 to thus separate the ball 28 from the valve seat 30 for valve opening. For a valve closing operation, the coil 52 is energized to induce a magnetic field wherein the permanent magnet 44a and the iron core 50 attract each other, as a result of which the operating part 44 is moved toward the iron core 50 and the pin 44b is separated from the ball 28 to thus cause the ball 28 to be seated for valve closing on the valve seat 30 by the gravity of the weight 32 and fluid pressure.</p> |
