Patent ID: 8659376

Claim:
A method of making a magnetically latched solenoid comprising: providing a housing, the housing comprising a housing first end, the housing at least partially defining a housing cavity through which an axis extends, the housing cavity having an essentially open housing mouth; inserting, into the housing cavity, the following: a moveable magnetically permeable member, the moveable magnetically permeable member comprising an axially extending central portion and an axially extending peripheral portion, and wherein a moveable member cavity is defined between the axially extending central portion and the axially extending peripheral portion; a spring for biasing the moveable magnetically permeable member toward the housing first end; inserting, through the housing mouth and into the housing cavity, the following: a pole member comprising a pole member mating surface; a counter flux generator, the counter flux generator being inserted at least partially into the moveable member cavity; a stationary case member which at least partially defines a case cavity and comprises a first magnetized mating surface, upon insertion of the stationary case member the case cavity being occupied at least partially by the counter flux generator and the pole member; a permanent magnet; a plate configured for inclusion in a magnetic circuit and within the case cavity, the magnetic circuit also comprising the pole member, the stationary case member, and the moveable magnetically permeable member; applying a force which acts on the pole member for driving the pole member mating surface toward the moveable magnetically permeable member and thereby adjusting a central air gap between the pole member mating surface and the moveable magnetically permeable member so that the central air gap occurs where the pole member has axial contact with the central magnetized mating surface of the moveable magnetically permeable member and so that the central air gap is dependent on a location of the moveable magnetically permeable member.