Patent ID: 7592729

Claim:
A three-phase machine having the following features: a primary part having N grooves and m electrical phase windings; a secondary part ( 1 ) having a number p of pole pairs (P 1 -P 4 ), each comprised of two magnetic poles ( 2 ) of different polarities; wherein the pole gap ( 6 ) is essentially the same for all of the pole pairs (P 1 -P 4 ) and results from an even distribution of all of the poles ( 2 ) on the secondary part ( 1 ); wherein at least one pole pair (P 1 -P 4 ), with no change to its pole gap ( 6 ), is shifted by a predetermined distance ( 5 ) in relation to an equidistant distribution of all of the pole pairs; and wherein with a groove/pole ratio N/P=3:2, the pole pairs (P 1 -P 4 ) p are shifted by approximately α v,p =v−1/p;v=1 . . . p ( 3 , 4 ) the wavelength of the 6×p th dominant harmonic of the detent torque in relation to the initial position dictated by the uniform distribution, thus reducing or enlarging the pole pair gaps ( 5 ).