Patent ID: 8106734

Claim:
A solenoid comprising: a housing comprising a housing first end, the housing at least partially defining a housing cavity, the housing cavity having an essentially open housing mouth; a moveable magnetically permeable member which translates at least partially within the housing from a latched position to a stroked position along an axis, the moveable magnetically permeable member comprising a moveable mating surface at least partially lying in a plane transverse to the axis when in the latched position; a stationary magnetic assembly situated at least partially in the housing and in the cavity inserted through the housing mouth, the stationary magnetic assembly comprising: a stationary case member which at least partially defines a case cavity and comprises a first magnetized mating surface; a pole member comprising a second magnetized mating surface; a permanent magnet, the permanent magnet generating a permanent magnetic flux field in the pole member, in the moveable magnetically permeable member, and in the stationary case member sufficient to retain the moveable magnetically permeable member essentially in contact with the stationary magnetically permeable assembly at an air gap interface between the stationary magnetically permeable assembly and the moveable magnetically permeable member when in the latched position; the pole member being selective positioned through the housing mouth and within the case cavity along the axis and whereby the second magnetized mating surface is positionable along the axis in a direction toward the moveable mating surface in a manner that is dependent only on the location of the movable magnetic mating surface; a plate for conducting the permanent magnetic flux field and completing a magnetic circuit comprising the stationary magnetically permeable member, the permanent magnet, the plate, and the moveable magnetically permeable member; a counter flux generator; a spring which biases the moveable magnetically permeable member away from the stationary magnetically permeable assembly when a counter flux generated by the counter flux generator overcomes the permanent magnetic flux.