Magnetic erasing head
AssigneeU.S. Philips Corporation
InventorJoseph H. Borghans
Life of this patent
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Abstract
A magnetic erasing head for use in a radio receiver/tape recorder combination, includes a housing, a core unit of ferrite and an electrical winding. The housing has an opening which leaves a surface of the core unit free for cooperation with a record carrier to be erased. In order to control the generation of higher harmonics of the erasing frequency which might interfere in particular with radio reception on the medium wave range, the core unit is constructed with an entirely open rear circuit. In other words, the usual closing part is absent.
Claims1
A magnetic erasing head for use in radio receiver/tape recorder combinations, comprising a housing, a core unit formed by core parts of a sintered oxidic ferromagnetic material and having ends which enclose erasing gaps between them, and an electric erase winding provided on one of the core parts, a surface of the housing having an aperture, the core unit being disposed in the housing such that said ends of the core parts are exposed through said aperture for cooperation with an associated magnetizable record carrier to be erased, characterized in that all of said core parts except at said erasing gaps are spaced apart to form completely open magnetic circuits remote from said erasing gaps to thereby minimize the generation of interference signals which are higher harmonics of the frequency of an erase signal, said core unit comprising two L-shaped core parts and an I-shaped core part, said I-shaped core part having first and second long sides which are mutually opposite, each L-shaped core part having a short limb and a long limb, each short limb having a blunt end, one of said L-shaped core parts being disposed with said blunt end thereof registered with and opposite to said first long side of said I-shaped core part to form a first erasing gap, the other of said L-shaped core parts being disposed with said blunt end thereof registered with and opposite to said second long side of said I-shaped core part to form a second erasing gap, and said erase winding is disposed on said I-shaped core part.
Dependencies are inferred from the claim text.