Linear motor, compressor equipped with linear motor, refrigerator equipped with compressor, and vehicle air suspension equipped with compressor

A linear motor comprising:

• a field element including a magnetic pole frame and a plurality of field element poles provided in the magnetic pole frame;
• and
• a plurality of armature magnetic poles around which windings are wound and that are provided to sandwich the field element, the field element and the armature magnetic poles are configured for a relative displacement, wherein the relative displacement comprises the field element moving within the linear motor from a center position to between a rearmost position and a stroke upper limit position,
• wherein the plurality of field element poles include a primary magnet arranged between the plurality of armature magnetic poles and a first secondary magnet of the one or more secondary magnets arranged externally relative to spaces between the plurality of armature magnetic poles in either direction of the relative displacement, and
• a neck part of the magnetic pole frame connected to a bearing is provided externally in the other direction of the relative displacement,
• wherein a first pitch between the plurality of armature magnetic poles is first value τp1, a second pitch between the plurality of field element poles is second value τp2, and the second value τp2 is greater than the first value τp1, and
• wherein a distance between a bearing side pole of the plurality of armature magnetic poles and a primary pole of the primary magnet is half the first value τp1 when the field element is at the center position.