Patent ID: 9691533
Date: 2017-06-27
CPC Classifications: H01F

Claim:
1. A magnetic circuit comprising: a plurality of permanent magnets disposed in an array; a pair of yokes which sandwich the plurality of permanent magnets, each yoke of the pair of yokes being without any openings; and a ferrous plate that is separated by a gap from the yokes and parallel to a length of the yokes, wherein: each of the plurality of permanent magnets have one magnetic pole disposed closer to one of the pair of yokes, and another magnetic pole disposed closer to the other of the pair of yokes, a space between the yokes where the permanent magnets exist includes only magnetic material where the plurality of permanent magnets are disposed, and a width of each of the yokes is narrower than a width of each of the plurality of permanent magnets such that there is a stepped structure along a length of the magnetic circuit such that the plurality of permanent magnets steps out from both yokes of the pair of yokes.