Systems and Methods for a Self-Shorting Bi-Stable Solenoid

A bi-stable solenoid comprising:

• a housing;
• a wire coil arranged within the housing;
• a first pole piece;
• a second pole piece;
• an armature including a permanent magnet, wherein the armature is movable between a first stable position and a second stable position;
• and
• an armature tube at least partially encloses the armature and includes a stop surface,
• wherein, when the armature is in the first stable position and the wire coil is de-energized, the armature engages the stop surface and a flux of the permanent magnet shorts through the first pole piece by forming a closed loop flux path that travels through the armature, the permanent magnet, and the first pole piece, wherein the stop surface holds the armature in an axial location where the closed loop flux path generates a force on the armature in a direction that urges the armature into the stop surface.

A bi-stable solenoid comprising:

• a housing;
• a wire coil arranged within the housing;
• a first pole piece;
• a second pole piece;
• an armature including a permanent magnet;
• and
• an armature tube at least partially enclosing the armature and including a stop surface;
• wherein selective energization of the wire coil is configured to move the armature between a first position and a second position,
• wherein, when the armature is in the first position, flux of the permanent magnet shorts through the first pole piece to establish a magnetic detent, and when the armature is in the second position, the flux of the permanent magnet maintains the armature in the second position with a magnetic latch established by engagement between the armature and the second pole piece, and wherein the stop surface holds the armature in an axial location where the magnetic detent generates a force on the armature in an axial direction away from the second pole piece.