Patent attributes
In a linear motor having permanent magnets placed on a slider, the slider has slider blocks disposed in such a manner that relative positions between front ends of the slider blocks in a slider moving direction and salient poles of two stators opposing the slider blocks is shifted by approximately 130 to 230 electrical degrees. Because the positions of the frond ends of the slider blocks in the slider moving direction relative to the stator salient poles of SIDE-A are shifted from those of SIDE-B by P/2 corresponding to 180 electrical degrees, thrust ripples occurring on SIDE-A and SIDE-B have a relationship such that they are displaced by P/2. As a result, the thrust ripples of SIDE-A and SIDE-B are canceled, thereby reducing a thrust ripple with P/3 periodicity.
