Electromagnetic actuator with response time calibration

A calibratable direct current electromagnetic actuator, comprising:

• a first coil, energized to produce a firs magnetic field;
• a second coil, energized to produce a second magnetic field directionally opposing said first magnetic field and lesser in magnitude than said first magnetic field, energization of said first and said second coils producing a resultant magnetic field with a magnitude equal to the difference between the magnitudes of said first and said second magnetic fields and directionally identical to said first magnetic field;
• a variable resistance element, connected with said second coil, the resistance being adjustable to variably affect current flow through said second coil, thereby affecting the magnitude of said second and said resultant magnetic fields;
• and
• an armature electromagnetically biased to a first position by said resultant magnetic field in response to energization of said first and said second coils and mechanically biased to a second position in response to deenergization of said first and said second coils, the armature being moved from the second position to the first position in a first armature response time in response to said energization of said first and second coils and moved from the first position to the second position in a second armature response time in response to said deenergization of said first and second coils;
• said variable resistance element having a value establishing the magnitude of the resultant magnetic field at a value whereby said first and said second armature response times are at predetermined values.