Patent ID: 8810082

Claim:
A linear motor comprising: a mover having a plurality of permanent magnets arranged so that magnetic poles of adjacent magnets are inverted; and an armature unit comprising a plurality of magnetic poles having a pair of magnet pole teeth oppositely arranged at both sides of the permanent magnets of said mover via an air gap an cores connecting between the pair of magnetic pole teeth, and a plurality of magnetic pole set comprising an armature winding(s) that are wound around said cores of the plurality of magnetic poles in common; wherein the linear motor generates thrust to move the armature unit and the mover relatively; and wherein the linear motor comprises a magnetic pole pair of which magnetic pole pitch (Pc) against the magnet pitch (P) of the permanent magnets is Pc=2nP±2P/qk, where n=1, 2, 3, . . . , a ripple component which should be reduced is k-th harmonic order, k=1, 2, 4, . . . , and q=number of magnetic poles constituting the magnetic pole pair.