| 摘要 |
An electrically operable actuator capable of being secured to a valve body to control the flow of fluid therethrough by the movement of a spring-loaded valve member supporting armature. The spring-loaded armature, at all times, tends to move to a first position where the valve member is in sealing engagement with a valve seat and flow of fluid through the valve body is obstructed. The actuator includes a permanent magnet and solenoid, each of which provides a separate source of magnetic flux. The armature is formed from magnetic stainless steel or other material having substantial permeability and low magnetic retentivity. When the magnetic flux from the permanent magnet and solenoid flow in the same direction relative to the armature, the armature is moved from a first fluid flow obstructing position to a second non-fluid flow obstructing position, and thereafter removably held in the second position by magnetic flux from the permanent magnet. When the magnetic flux from the permanent magnet is nullified, the spring moves the armature from the second to the first position.
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