Systems and methods for a solenoid having a permanent magnet

A solenoid, comprising:

• a housing;
• a pole piece;
• an end plate formed with or coupled to the housing;
• a wire coil arranged within the housing;
• a permanent magnet arranged between the pole piece and the end plate;
• an armature configured to move between a first position and a second position in response to a current applied to the wire coil;
• a pin coupled to the armature, wherein the pole piece includes a bearing protrusion that extends axially from the end plate and that includes a bearing surface that slidably receives the pin;
• and
• a spring configured to bias the armature, wherein when the wire coil is de-energized, the armature is maintained in at least one of the first position and the second position, and wherein the first position is configured to be maintained by the spring and the second position is configured to be maintained by magnetic attraction between the armature and the permanent magnet through engagement between the armature and the pole piece,
• wherein the pole piece includes a thin-walled portion that extends through the permanent magnet and is dimensioned so that magnetic flux generated by the permanent magnet saturates in the thin-walled portion.

A solenoid, comprising:

• a housing;
• a pole piece;
• an end plate formed with or coupled to the housing;
• a wire coil arranged within the housing;
• a permanent magnet arranged axially between the pole piece and the end plate;
• an armature configured to move between a first position and a second position in response to a current applied to the wire coil;
• a pin coupled to the armature, wherein the pole piece or the end plate includes a bearing protrusion that extends axially away from an exterior surface of the end plate and includes a bearing surface that is configured to slidably receive the pin;
• and
• an armature tube that movably receives the armature,
• wherein the pole piece includes a thin-walled portion that extends through the permanent magnet and is dimensioned so that magnetic flux generated by the permanent magnet saturates in the thin-walled portion.