A coreless linear motor and a canned linear motor that can significantly reduce an increase in surface temperature of a linear motor armature are provided.In a magnetic field system of a coreless linear motor 1a, two rows of permanent magnets 201a are disposed on the opposite sides in a magnetic field yoke 202, and an armature 101a is disposed so that armature coils 102a and 103a including a plurality of coil groups centrally wound in the magnetic field system having the two rows of permanent magnets are arranged in two rows. One end of the two rows of the armature coils 102a and 103a in a direction perpendicular to a direction of a magnetic gap between the two rows of permanent magnets branches into two parts, and the other end is arranged back-to-back. Further, the substrate 104a for connecting the coils is inserted into a gap between the two rows of the branching coils 102a and 103a. The armature coils 102a and 103a and the substrate 104a are integrally formed and fixed by mold resin 105.

A linear motor includes a magnet, a coil, and a jacket having an inside member that is comb-shaped having teeth, extending along a driving direction. The coil is engaged by the teeth of the comb-shaped member. A cooling medium flows through an inside space enclosed by the jacket. Unwanted deformation or breakage of the jacket can be avoided even if the pressure of the cooling medium is enlarged or the thickness of a small-thickness portion of the jacket is made smaller. A higher cooling efficiency is thus attainable by increasing the flow rate of the cooling medium.

A canned linear motor such that increase of the temperature of the mover is suppressed, the viscous damping force is reduced, and the strength of the can does not deteriorate. A canned linear motor comprises two parts, in one of which a permanent magnet is provided as a field system and in the other of which a three-phase armature winding, a winding fixing frame for supporting the armature winding, a coolant passage through which a coolant for cooling the surface of the armature winding passes, a can (14) covering the armature winding and the coolant passage, and a header (14') for sealing the can. Slits (151, 152) extending in the direction of travel and parallel to each other are formed in the can (14).

A first armature winding and a second armature winding each include a tubular member, a first conductor arranged in a radially inner side of the tubular member, and a second conductor arranged in a radially outer side of the tubular member. The first conductor includes a first coated portion, which is coated by a coating formed from an insulator, and a first wire connection portion, which is free from the insulator. The second conductor includes a second coated portion, which is coated by a coating formed from an insulator, and a second wire connection portion, which is free from the insulator. The first wire connection portion and the second wire connection portion are electrically connected to each other. A large output is obtained from a slotless motor including the first armature winding and the second armature winding.

A slider unit having built in a moving-coil linear motor is incorporated in a linear motion guide unit having a track rail and a slide. The slider unit is made easy in mounting to the appliances or works. The linear motion guide unit has the track rail and the slider movable lengthwise of the track rail. A linear motor is arranged between any one of widthwise opposing side walls of the track rail and the slider, and composed of a stator comprising a magnet yoke and field magnets, and a moving-coil assembly held on a side edge of a mount of the slider. The linear motor is preferred to make compact or slim in construction the linear motion guide unit, in which the linear motor is incorporated, thus making the slider unit simple in construction.