Moving coil actuator utilizing flux-focused interleaved magnetic circuit

A moving coil linear actuator comprising:

• a cylindrical shell having a closed end and an open end;
• a core disposed within the shell to define an annular air gap therebetween, the core including a plurality of sets of axially-magnetized cylindrical permanent magnets separated from one another by ferro-magnetic pole pieces and having alternating directions of magnetization, the sets of magnets including an innermost magnet set disposed in proximity to the closed end of the shell and an outermost magnet set disposed in proximity to the open end of the shell, the outermost magnet set having a ferro-magnetic pole piece disposed between said outermost magnet set and the open end of the shell;
• and
• a coil assembly movably disposed within the annular air gap, the coil assembly including a coil carrier disposed within the annular air gap and a plurality of coil windings formed on the coil carrier in axial correspondence to the plurality of sets of magnets, being wound to have alternating polarities such that adjacent coil windings are wound in series opposition, and connectable to an electrical power supply.

A moving coil actuator comprising:

• a shell having a closed end and an open end;
• a core disposed within the shell to define an air gap therebetween, the core including first axially-magnetized permanent magnet means having a first direction of magnetization and disposed in proximity to the closed end of the shell, second axially-magnetized permanent magnet means having a second direction of magnetization opposite to the first direction of magnetization and disposed in proximity to the open end of the shell, a first ferro-magnetic pole piece disposed between the first magnet means and the second magnet means, and a second ferro-magnetic pole piece disposed between the second magnet means and the open end of the shell;
• and
• a coil assembly movably disposed within the air gap and connectable to an electrical power supply, the coil assembly including a coil carrier disposed within the gap, a first coil winding formed on the coil carrier in proximity to the first magnet means and wound to have a first polarity, and a second coil winding formed on the coil carrier in proximity to the second magnet means and wound to have a second polarity opposite to the first polarity such that the first and second coil windings are wound in series opposition.

A moving coil actuator comprising:

• a shell having a closed end and an open end;
• a core disposed within the shell to define an air gap therebetween, the core including a plurality of sets of axially-magnetized permanent magnets separated from one another by ferro-magnetic pole pieces and having alternating directions of magnetization, the sets of magnets including an innermost magnet set disposed in proximity to the closed end of the shell and an outermost magnet set disposed in proximity to the open end of the shell, the outermost magnet set having a ferro-magnetic pole piece disposed between said outermost magnet set and the open end of the shell;
• and
• a coil assembly movably disposed within the air gap, the coil assembly including a coil carrier disposed within the air gap and a plurality of coil windings formed on the coil carrier in axial correspondence to the plurality of sets of magnets, being wound to have alternating polarities such that adjacent coil windings are wound in series opposition, and connectable to an electrical power supply.