| 摘要 |
<p>The device comprises a housing having therein a valve chamber, fluid inlet and exhaust ports opening on opposite ends, respectively, of the chamber, and an outlet port for connection to fluid pressure operated apparatus. Two solenoid coils are wound in the housing to surround said chamber and two armatures which are mounted in the chamber to reciprocate independently of each between said inlet and exhaust ports. Two springs normally urge said armatures to first limit positions in which a valve on one armature closes the exhaust port, and a valve on the other armature opens the inlet port to place it in communication with the outlet port. When both solenoid coils are energized the armatures shift in the same direction to close the inlet port and open the exhaust port to exhaust fluid from the outlet port to a sump. One coil alone may be energized to shift one armature to close the inlet port without causing the other armature to shift, thus maintaining the exhaust port closed.</p> |
