Magnetic disk recording and reproducing apparatus
AssigneeTDK Corporation
InventorsKazumasa Fukuda, Masanori Sakai, Mikio Matsuzaki, Joichiro Ezaki
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Abstract
A thin film magnetic head includes a slider and thin film magnetic transducers, the slider supporting the thin film magnetic transducers. At least one of these thin film magnetic transducers is a magnetoresistive read element. The surface resistivity .rho. of the magnetic film of the magnetic disk is within the range of .rho..gtoreq.0.03.OMEGA..multidot.cm. Electric leak from the thin film magnetic head to the magnetic disk and electric discharge between these two are prevented.
Claims28
A magnetic disk recording and reproducing apparatus comprising a thin film magnetic head in combination with a magnetic disk, wherein:
- said thin film magnetic head includes a slider and thin film magnetic transducers,
- said slider supports said thin film magnetic transducers,
- at least one of said thin film magnetic transducers is a read element comprising a magnetoresistive element through which sense current runs and which is present on the surface of said slider facing said magnetic disk, wherein a longitudinal direction of said magnetoresistive element is parallel to the magnetic disk,
- said disk is linked with a drive unit which is at a first electrical potential, and
- said magnetoresistive element is coupled to a second electrical potential which is equal to said first electrical potential,
- a surface resistivity .rho. of a surface layer of said magnetic disk as an outermost surface facing the thin film magnetic head is within a range of .rho..gtoreq.0.03.OMEGA..multidot.cm to thereby prevent electric leakage of said sense current and discharge between said magnetoresistive element and said magnetic disk even if said magnetoresistive element contacts said magnetic disk during operation by passing the sense current through the magnetoresistive element to the second electrical potential when said magnetoresistive element contacts said magnetic disk.
A magnetic disk recording and reproducing system comprising:
- a thin film magnetic head comprising:
- a slider;
- and
- a plurality of thin film transducers formed on the slider;
- a magnetic disk linked with a drive unit which is at a first electrical potential;
- wherein at least one of the plurality of thin film transducers is a read element comprising a magnetoresistive element through which sense current runs and which is present on the surface of said slider facing said magnetic disk, wherein a longitudinal direction of said magnetoresistive element is parallel to the magnetic disk;
- said magnetoresistive element is coupled to a second electrical potential which is equal to said first electrical potential,
- said magnetic disk comprising a surface layer as an outermost surface facing the thin film magnetic head having a surface resistivity greater than or equal to 0.03.OMEGA..multidot.cm to thereby prevent electric leakage of said sense current and discharge between said magnetoresistive element and said magnetic disk even if said magnetoresistive element contacts said magnetic disk during operation by passing the sense current through the magnetoresistive element to the second electrical potential when said magnetoresistive element contacts said magnetic disk.
A method for preventing sense current which runs through a magnetoresistive element mounted on a thin film magnetic head, from leaking from said magnetoresistive element to a magnetic disk when said magnetoresistive element contacts said magnetic disk;
- said thin film magnetic head including a slider, supporting said magnetoresistive element;
- said magnetoresistive element being formed on a surface of said slider facing said magnetic disk, wherein a longitudinal direction of said magnetoresistive element is parallel to the magnetic disk;
- and
- said magnetic disk being linked with a drive unit which is at a first electrical potential and said magnetoresistive element being coupled to a second electrical potential which is equal to said first electrical potential, wherein:
- a surface resistivity .rho. of a surface layer of said magnetic disk as an outermost surface facing the thin film magnetic head is within the range of .rho.>0.03.OMEGA..multidot.cm to thereby prevent electric leakage of said sense current and discharge between said magnetoresistive element and said magnetic disk even if said magnetoresistive element contacts said magnetic disk during operation by passing the sense current through the magnetoresistive element to the second electrical potential when said magnetoresistive element contacts said magnetic disk.
Dependencies are inferred from the claim text.