Abstract: An electromagnetic induction heating device includes a rotator in which a plurality of magnets is arranged in a manner that the same poles are positioned on a side of an object to be heated, and a rotation drive part for rotating the rotator, and heats the object to be heated by an induction current which is generated by rotating the rotator, wherein magnets adjacent in a direction in which the rotator is rotated are arranged with an interval of 10 mm or more. Thereby, heating efficiency by electromagnetic induction is improved, and the object to be heated such as an aluminium material or the like can be brought to a predetermined temperature in a short time.

Abstract: To show an electromagnetic induction heating apparatus in which an object to be heated such as a half-finished light alloy wheel can be heated efficiently to have a predetermined temperature in a short time. An electromagnetic induction heating apparatus 1 includes a rotating body 2 with a plurality of magnets 21 arranged such that the same pole is positioned on the side of an object to be heated 8 and a rotation driving motor 3 for rotating the rotating body 2, in which the object to be heated 8 is heated by an induced current generated when the rotating body 2 is rotated. By controlling the distance D between the magnets 21 of the rotating body 2 and the object to be heated 8 with a moving motor 6, a light alloy wheel or the like, which has a high thermal expansion coefficient, can be well-heated efficiently.

Abstract: To show an electromagnetic induction heating apparatus in which an object to be heated such as a half-finished light alloy wheel can be heated efficiently to have a predetermined temperature in a short time. An electromagnetic induction heating apparatus 1 includes a rotating body 2 with a plurality of magnets 21 arranged such that the same pole is positioned on the side of an object to be heated 8 and a rotation driving motor 3 for rotating the rotating body 2, in which the object to be heated 8 is heated by an induced current generated when the rotating body 2 is rotated. By controlling the distance D between the magnets 21 of the rotating body 2 and the object to be heated 8 with a moving motor 6, a light alloy wheel or the like, which has a high thermal expansion coefficient, can be well-heated efficiently.

Abstract: In production of a gap spacer for magnetic heads in electric and electronic appliances, accumulation of a non-magnetic material insoluble to acids or alkalis on a thin base soluble to these solvents is employed with use of a proper mask as a substitute for the conventional rolling process. Stable growth in thickness of the non-magnetic material during the accumulation process assures highly precise thickness uniformity of the product via easy time control of the process and absence of the rolling process allows broader freedom in choice of the material.