| 摘要 |
<p>A medical nuclear magnetic resonance system is provided with a primary field magnet assembly having a ferromagnetic frame (22) defining a patient-receiving space (58) adapted to receive a human body (P). The frame has a pair of opposed polar regions (36, 38) aligned on a polar axis (34) and disposed on opposite sides of the patient-receiving space. Superconducting windings (80, 90) are supported in proximity to the frame so that when a current passes through the windings it produces a magnetic field within the patient-receiving space, and at least a portion of the flux passes into the patient-receiving space by way of the polar region. Accordingly, the magnetic forces on the coil windings are likewise reduced, thereby minimizing the forces applied to displace the coil windings during operation.</p> |
