The energy from the magnetiser is delivered to the permanent magnet material to magnetise via the fixture coil or fixture. The fixture has the precise mechanical dimensions needed to hold the magnet or magnet assembly in place and the wound coils required to deliver the energy to the magnetised part. Magnetising fixtures are usually made of single or multiple wound coils of wire encased in a high-performance glass fibre resin for strength and stability. Sometimes, a mechanical clamp is used. Much energy is used in the magnetising process, and fixtures are often cooled to increase production throughput. In addition, the large magnetic fields used in the magnetising process can be hazardous to health; thus, guard rails or automated part handling is needed to ensure safe operation. The detailed design process Proton conducts for each fixture covers all mechanical handling, production throughput, and health and safety requirements. The number of poles used in a fixture refers to the magnetic poles the magnetised part has. For applications like a single magnet, a 2-pole fixture is needed (north and south), and the fixture usually only has one coil to deliver the energy to the magnet to magnetise it. The applications for two-pole devices typically involve single magnet calibration, sensor parts, or navigation compass production. Most fixtures are custom, including multi-pole axial fixtures (the axis of the coil and the magnet are the same) and multi-pole radial designs. Proton has produced magnetised magnets for the most miniature fixtures, which are a few millimetres in diameter. Custom and radial magnetisers are our special focus for R&D.
