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Permanent magnet structure for generation of magnetic fields
Iowa State University Patents
  • Seong-Jae Lee, Iowa State University
  • David C. Jiles, Iowa State University
  • Karl A. Gschneidner, Jr., Iowa State University
  • Vitalij K. Pecharsky, Iowa State University
Document Type
Publication Date

A permanent magnet structure for maximizing the flux density per weight of magnetic material comprising a hollow body flux source for generating a magnetic field in the central gap of the hollow body, the magnetic field having a flux density greater than the residual flux density of the hollow body flux source. The hollow body flux source has a generally elliptic-shape, defined by unequal major and minor axis. These elliptic-shaped permanent magnet structures exhibit a higher flux density at the center gap while minimizing the amount of magnetic material used. Inserts of soft magnetic material proximate the central gap, and a shell of soft magnetic material surrounding the hollow body can further increase the strength of the magnetic field in the central gap by reducing the magnetic flux leakage and focusing the flux density lines in the central gap.

Patent Number
US 6,680,663 B1
ISURF Reference Number


Iowa State University Research Foundation, Inc.,
Application Number
US 09/814,640
Date Filed
File Format
Citation Information
Seong-Jae Lee, David C. Jiles, Karl A. Gschneidner and Vitalij K. Pecharsky. "Permanent magnet structure for generation of magnetic fields" (2004)
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