Linear motor, compressor equipped with linear motor and equipment equipped with linear motor

A linear motor comprising:

• a first armature having two sets of an upper winding and a lower winding opposed to the upper winding through a gap in a vertical direction;
• a moving member having a permanent magnet and enabled to reciprocate in a longitudinal direction with respect to the first armature;
• a current detecting unit that detects an electric current carried through the first armature;
• and
• a resistor, a coil, or a capacitor, or two or more resistors, coils, or capacitors connected between the two upper windings or between the two lower windings,
• wherein the two upper windings are in series connection,
• wherein the two lower windings are in series connection,
• wherein the sets of the upper winding and the lower winding are in parallel connection, and
• wherein the current detecting unit includes a current sensor that detects an electric current carried through one of the resistor, the coil, or the capacitor, or an electric current carried through the two or more resistors, coils, or capacitors.

A linear motor comprising:

• a first armature having two sets of an upper winding and a lower winding opposed to the upper winding through a gap in a vertical direction;
• a moving member having a permanent magnet and enabled to reciprocate in a longitudinal direction with respect to the first armature;
• and
• a current detecting unit that detects an electric current carried through the first armature, wherein the two upper windings are in parallel connection,
• wherein the two lower windings are in parallel connection, and
• wherein the sets of the upper winding and the lower winding are in parallel connection.

A compressor comprising:

• a moving member having a permanent magnet;
• a first armature having an upper winding and a lower winding opposed to the upper winding through a gap in a vertical direction, and configured to apply thrust and reciprocate the moving member in a longitudinal direction;
• a second armature configured to apply a levitation force to the moving member;
• a current detecting unit that detects an electric current carried through the first armature;
• a controller configured to apply respective electric currents to the first armature and the two second armatures;
• a piston connected to one end of the moving member;
• and
• a cylinder on which the piston is slid,
• wherein the upper winding and the lower winding are in parallel connection,
• wherein the two second armatures are provided in the longitudinal direction, and one of the two second armatures is provided at a front of a center of gravity of the moving member and the other of the two second armatures is provided at a rear of the center of gravity of the moving member, and
• wherein the controller is configured to magnetize each of the two second armatures to have a same polarity as the permanent magnet respectively opposed thereto.