Abstract: A permanent magnet latching solenoid with a central passage carrying a reciprocative armature has a magnetically permeable bushing press-fit in each end of the bobbin. The outer ends of the bushings define the outer ends of the bore. A separate preformed magnetically permeable frame surrounds the bobbin and includes end wall portions that abut the outer ends of the bushings. The bobbin assembly is inserted laterally into the frame, with the ends of the bushings against the ends of the frame. Openings in the end walls of the frame accommodate free passage of an operator rod element which is affixed to the armature.

Abstract: An emergency manual actuation mechanism for a conventional solenoid having a plunger with one end connected to an external apparatus, such as a diesel engine fuel pump, in which energization of the solenoid coil retracts the plunger axially; the mechanism comprises a non-magnetic retraction rod that extends into the solenoid housing in alignment with the solenoid plunger and is axially movable from a normal position disengaged from the plunger to an intermediate position at which a mechanical connection is completed between the rod and the plunger. Further axial or rotary movement of the retraction rod to a retraction position drives the plunger to its retracted position, simulating energization of the solenoid coil. Retainer means hold the retraction rod and the solenoid plunger at their retracted positions.

Abstract: An internal latching mechanism for a solenoid comprises a cylindrical ball race on the main solenoid plunger with a plurality of balls disposed in aligned apertures in the ball race. First and second axially displaced fixed retainers, interconnected by a shoulder, define the limits of ball movement in one radial direction for the unactuated and actuated positions of the main plunger, and third and fourth axially displaced retainers perform the same function for the opposite radial direction; the fourth retainer is a movable retainer connected to a latch release plunger. When the main solenoid coil is energized to drive the main plunger to its actuated position, the balls displace the fourth retainer enough to allow the balls to move into engagement with the second and fourth retainers; when the main coil is de-energized the balls engage the shoulder between the first and second retainers to latch the main plunger in actuated position.

Abstract: An internal latching mechanism for a solenoid comprises a cylindrical ball race on the main solenoid plunger with a plurality of balls disposed in aligned apertures in the ball race. First and second axially displaced fixed retainers, interconnected by a shoulder, define the limits of ball movement in one radial direction for the unactuated and actuated positions of the main plunger, and third and fourth axially displaced retainers perform the same function for the opposite radial direction; the fourth retainer is a movable retainer connected to a latch release plunger. When the main solenoid coil is energized to drive the main plunger to its actuated position, the balls displace the fourth retainer enough to allow the balls to move into engagement with the second and fourth retainers; when the main coil is de-energized the balls engage the shoulder between the first and second retainers to latch the main plunger in actuated position.