Adjustable solenoid

A method for adjusting the stroke and force of a plunger of a solenoid actuator, comprising:

• providing a solenoid actuator comprising a solenoid defining a plunger bore and a plunger, the plunger including a stem and an armature, the armature including an axial armature bore, the stem engaged with the armature bore and adapted for advancement of the armature along at least a portion of the stem, the plunger comprising a plunger first end and a plunger second end, the stem comprising a head, a tail opposite the head, and a body therebetween, the body comprising an elongated member having a stem threaded portion, the tail including a tail retention element, the armature comprising a cylindrical member adapted for sliding reception within the plunger bore, the armature comprising an armature first end and an armature second end opposite the armature first end, the armature comprising a material highly permeable to a magnetic field, wherein the solenoid comprises a coil defining the plunger bore about an axis, a housing defining a cavity adapted to house the solenoid, the housing including a housing first end and a housing second end opposite the housing first end, the housing first end defining a housing aperture substantially coaxial with the plunger bore, a back stop disposed in and adapted to substantially enclose the housing second end and retain the solenoid within the housing, the back stop comprising a back stop inner flange and a back stop seat, the back stop inner flange defining a back stop aperture substantially coaxial with the plunger bore, the back stop seat adapted to extend into the plunger bore, a spring, wherein the armature second end further comprises a spring seat adjacent the armature bore, the spring seat adapted to accept an end of the spring, the plunger second end extending into the plunger bore through the housing aperture, the housing aperture adapted to allow the plunger first end to pass through the plunger bore through the housing aperture, the spring disposed within the plunger bore between the back stop inner flange and the spring seat of the armature, the back stop adapted to prevent the armature from passing through the housing second end, the back stop adapted to allow the tail to pass through the housing second end, the spring adapted to provide an urging bias acting to urge the armature away from the back stop, the plunger disposed within the plunger bore with at least a portion of the tail including the tail retention element extending from the plunger bore and through the back stop aperture, the plunger retained in engagement with the solenoid by the engagement of a fastener coupled to the tail retention element, the fastener adapted to capture the back stop inner flange between the armature and the fastener, the tail retention element comprising a tail threaded portion, the fastener adapted for threadable engagement with the tail threaded portion;
• and
• adjusting the location of the fastener on the tail threaded portion so as to adjust the extension of the head from the housing aperture a predetermined distance defined by the location of the fastener along the tail threaded portion.