Homopolar / Radial Fixture

Radial or Homopolar magnetising fixtures are designed to produce a single radial pole on the inner and outer diameters of a ring magnet. They are in essence constructed from two opposing axial field solenoids, such that the opposing flux is forced radially outwards in the region between the two coils.

The consequence of having two opposing coils is that they both generate very high opposing forces which try and force the coils apart. In addition, the magnitude of the field in the centre of each coil is significantly higher than in the magnet region and so the mechanical construction of these fixtures is paramount. It is not surprising that these fixtures have been known to be called ‘bucking coils’ as they can jump around of not mechanical restrained.

Not all magnets are suitable for radial magnetisation. The ideal shape is a washer shape magnet where the length to diameter ratio is small. The longer the magnet is, the more distorted the radial field becomes and the higher the higher fields in the centre of the coil need to be to fully saturate the full length of the magnet. Further information on this can be found in the attached technical paper.

Homopolar Radial Magnetising Fixture

Applications

  • Sintered radial ring magnets
  • Isotropic ring magnets
  • Linear Actuators
  • Passive magnetic bearings

Options

  • Water or air cooling available
  • Over Temperature Trips