PURPOSE: To demagnetize a magnetic material accurately and efficiently without hands by DC-magnetizing the magnetic material so as to have remanent magnetism having specified magnitude and distribution and demagnetizing the DC- magnetized magnetic material.
CONSTITUTION: The distribution of the remanent magnetism of a magnetic material is kept constant by giving the magnetic material a fixed magnetic field before demagnetization, and the magnetic material is demagnetized after the magnetic material is given the fixed magnetic field, thus positively shortening the remanent period of the magnetic material. A material to be demagnetized 8 being carried on a table line is magnetized by a second DC coil 26 for a through type coil system magnetizer first. The magnetomotive force of the second DC coil 26 at that time is 10,000AT. The material to be demagnetized 8 DC magnetized is carried further onto the table line, and demagnetized by a demagnetizer (a code DM) by using an AC-DC overlapping method.
TOKUMARU TOYOHISA