AN APPARATUS FOR ALTERING THE MAGNETIC STATE OF A PERMANENT MAGNET

摘要

An apparatus (10) for altering the magnetic state of a permanent magnet comprises a coil inductor (26) for generating and applying an induced magnetic field to the permanent magnet. The coil inductor (26) is provided in circuit between two charge storage elements (20, 24). The apparatus also comprises a discharge control circuit (28) for transferring charge alternately in opposed directions between the storage elements (20, 24) through the coil inductor (26) to generate a series of alternating polarity magnetic field pulses (167, 191) of decreasing magnitude in the coil inductor (26) or to generate a single magnetic pulse of relatively high strength. The apparatus (10) can be operated as either a magnetising or demagnetising device and is capable of demagnetising a column of 200 or more magnets.