PURPOSE: To easily and effectively reduce the load on a linear motor by making an upward magnetic force and downward dead load of a magnet act to the magnet by fitting a magnetic circuit forming a yoke to the casing of a moving section above the magnet.

CONSTITUTION: At the time of sliding a casing 5 in the axial direction together with a shaft 13 by applying an upward or downward magnetic force to a magnet 16 by making an electric current to flow to a winding coil 3, a force which moves the magnet 16 upward is generated by bringing the magnetic circuit B of a linear motor to a position above the magnet 16. In addition, since the dead loads of the magnet 16, casing 15, and shaft 13 act as forces which move the magnet 16 downward, the upward magnetic force and downward dead loads act on the magnet 16. Therefore, the size and weight of the linear motor can be reduced, because the load of the motor can be reduced and the current value of the motor at the lifting time and standstill time can be reduced.