Patent ID: 7215231

Claim:
A magnetic resonance imaging (MRI) magnet assembly, comprising: a ferromagnetic frame comprising: opposing, vertical, ferromagnetic elements; opposing, horizontal, upper and lower ferromagnetic pole supports connected to the vertical ferromagnetic supports; opposing upper and lower poles separated by a distance to define an imaging volume therebetween; at least one member extending from each vertical ferromagnetic element; and a source of magnetic flux associated with the ferromagnetic frame; wherein: the lower pole is supported by the lower ferromagnetic pole support; the upper pole is movably supported with respect to the upper pole support to vary the distance between the upper pole and the lower pole between one position, wherein the upper pole is separated from the lower pole by a first distance, and an other position, wherein the upper pole is separated from the lower pole by a second distance greater than the first distance; and the at least one member is positioned to support the upper pole when the upper pole is in the one position, and not support the upper pole when the upper pole is in the other position.