Thermo-magnetic recording head
AssigneeThomson-CSF
InventorsPhilippe Bousquet, Jean-Claude Lehureau
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Abstract
The thermo-magnetic head disclosed has a gap with magnetic properties at ambient temperature. This gap is heated above its Curie temperature in order to make it lose its magnetic property. The pole pieces on either side of the gap form electrical conductors which convey the heating current of this gap.
Claims23
A magnetic head comprising:
- a gap of a first material with magnetic properties at ambient temperature;
- heating means to heat the material of the gap beyond the Curie temperature in order to make said gap material lose its magnetic properties;
- and
- magnetic pole pieces of a second material on each side of the gap said pieces forming electrical conductors for conveying heating current to heat the gap material.
A magnetic head having two pole pieces of thin layers of first and second thicknesses wherein said pole pieces are separated by gap of a first material, wherein the gap material is extended to form a shoulder layer on which there is deposited one of said two pole piece thin layers having a first thickness, said gap shoulder layer having a thickness less than the thickness of the other one of said pole piece layers having said second thickness and wherein said gap material is a material which is magnetic at ambient temperature, said magnetic head further including a heating means for heating the gap material to a temperature above the Curie point in order to make said gap material lose its magnetic properties.
Dependencies are inferred from the claim text.