Patent ID: 7463129

Claim:
A magnet structure, comprising: A) a permanent magnet assembly, including i) an enclosure having an open portion, and ii) a magnetic mass disposed within the enclosure, and B) first and second pole assemblies, i) wherein the first pole assembly includes a) a first base portion, disposed within the enclosure, b) a first pole extension, extending from the first base portion outward from the enclosure, and c) a first pole on the first pole extension, having a pole face, ii) wherein the second pole assembly includes a) a second base portion, disposed within the enclosure, b) a second pole extension, extending from the second base portion outward from the enclosure, and c) a second pole on the second pole extension, having a pole face, wherein the first and second pole assemblies are arranged such that the pole face of the first pole opposes the pole face of the second pole; wherein the magnetic mass is a plurality of discrete magnetic elements made from a first magnetic material; wherein the discrete magnetic elements are bricks made from a first magnetic material; wherein the bricks are stacked within the enclosure; wherein the enclosure includes a closed bottom surface that supports the bricks, first and second sidewalls extending upward from first and second sides of the closed bottom surface, a rear wall extending upward from a back end of the closed bottom surface, a front wall extending upward from a front side of the closed bottom surface, and an open top area; wherein the first and second sidewalls extend upward to a first height, and wherein the front wall extends upward to a second height that is lower than the first height.