Patent ID: 6946941

Claim:
A permanent magnet assembly comprising: an arc-shaped flux return section formed of magnetically permeable material and extending along a portion of an arc and having an upper portion with a first end and a second end, a lower portion with a first end and a second end, and a middle portion with a first end and a second end, wherein the first end of the upper portion is operatively coupled to the first end of the middle portion and the first end of the lower portion is operatively coupled to the second end of the middle portion; an upper arc-shaped permanent magnet section having a north end and a south end, wherein the north end of the upper arc-shaped permanent magnet section is operatively coupled to the second end of the upper portion of the arc-shaped flux return section; and a lower arc-shaped permanent magnet section having a north end and a south end, wherein the south end of the lower arc-shaped permanent magnet section is operatively coupled to the second end of the lower portion of the arc-shaped flux return section; wherein an arc-shaped gap is formed between the south end of the upper arc-shaped permanent magnet section and the north end of the lower arc-shaped permanent magnet section.