Ngk Insulators, Inc.

Applied Magnetics, LLC

Nobuhiro Terada

Soichiro Matsuzawa

Fuminori Takeya

Michael I Aronoff

Hiroaki Yui

Masataka Shimizu

Hideto Sandaiji

Naoya Fukuda

Yayo Akai

Masahiro Masuda

Masatomo Yamauchi

Eigo Hirotsuzi

Tetsuo Miwa

A magnetic head core slider including an air bearing and a core portion with a magnetic gap provided adjacent one of lengthwise opposite ends of the air bearing. A preliminary track is defined by preliminary width-defining grooves such that the preliminary track extends across the magnetic gap in the direction of extension of the air bearing, each groove having a depth larger than the depth of the magnetic gap. An effective track is defined by a pair of opposed final width-defining recesses formed adjacent to the magnetic gap such that the effective track extends across the magnetic gap in the direction of extension of the air bearing. The length and width of the effective track are smaller than those of the preliminary track, and the width of the effective track determines the nominal width of the magnetic gap. Each recess has a depth smaller than that of the preliminary width-defining grooves but larger than that of the magnetic gap. Also disclosed is a process of fabricating the head core slider.

Core slider for magnetic disk, having opposed recesses defining narrow

A ferrite plate and a ceramic plate are joined to each other by a glass layer interposed therebetween. The ferrite plate and the ceramic plate thus joined to each other by the glass layer serve as a trailing core in the form of a composite for use in a magnetic head. Only the ferrite plate is exposed on a slidable surface to prevent the trailing core from being deformed or cracked. The trailing core has low inductance for high-density recording to prevent the magnetic head from causing recording/reading errors.

Method of manufacturing a composite magnetic head

A thin-film magnetic circuit board is disclosed which includes: a substrate formed of a non-magnetic material; a connector formed from a magnetic film on one major surface of the substrate, the connector having opposite end portions which protrude from the substrate to form a pair of protrusions; at least one coil formed from an electrically conductive film to provide a circuit pattern on the one major surface of the substrate, each coil having a spiral shape and surrounding a corresponding one of at least one of the protrusions of the connector; and a pair of leads which are electrically connected to opposite ends of the circuit pattern formed by the coil(s). Also is disclosed a magnetic head including this thin-film magnetic circuit board and a core element having a magnetic gap.

Thin-film magnetic circuit board and magnetic head using the same

A core chip for a magnetic head core slider, including a first and a second core member which are bonded together so as to define a coil-winding aperture. The two core members cooperate to provide a gap-forming portion defining a magnetic gap on one side of the coil-winding aperture, and a cut-off portion provided adjacent to the gap-forming portion. The cut-off portion is removed by grinding at the top surface to establish the nominal depth of the magnetic gap. The cut-off portion has a distance marker which extends from the top surface down to the gap-forming portion and which has an end portion adjacent to the gap-forming portion. The end portion is shaped so as to indicate a distance between the top surface and the gap-forming portion, that is, the depth of the magnetic gap, when the cut-off portion is removed to provide a sliding surface of the core chip in which the magnetic gap is open. Also disclosed is a process of fabricating the magnetic head core slider using the core chip.

Process for fabricating a magnetic head core slider

A thin-film magnetic circuit board is disclosed which includes: a first and a second substrate formed of a magnetic material; a non-magnetic layer for bonding these substrates to each other; at least one coil formed from an electrically conductive film to provide a circuit pattern, each coil having a spiral shape and surrounding a predetermined blank portion of at least one of the first and second substrates; a pair of leads which are electrically connected to opposite ends of the circuit pattern formed by the coil(s); and a connector formed from a magnetic film, for magnetically connecting the first and second substrates. The connector is fixed to the predetermined blank portion of the first and/or second substrates. Also is disclosed a magnetic head including this thin-film magnetic circuit board.

Method of producing a core slider for a rigid magnetic disk drive, including a slider body having air bearing portions, and a core chip which has a magnetic gap for writing and reading information and which is integrally secured to the slider body. The slider body consists of a ferrite section which includes at least the air bearing portions and which is formed of Mn--Zn ferrite, and a non-magnetic ceramic section formed of a non-magnetic ceramic material. The core chip is accommodated in a groove formed in the slider body and bonded to the slider body by a glass material.

Method of producing core slider for rigid magnetic disc drive

A thin-film magnetic head including: a slider body formed of a ferrite material and having air bearing portions on one major surface thereof on which a magnetic recording medium is slidable; a non-magnetic layer formed in the slider body such that the non-magnetic layer is located at least on a trailing end face of each of the air bearing portions, the non-magnetic layer having a thickness of at least 20 .mu.m; a head portion including an upper and a lower magnetic layer and a coil which are positioned within an area of the non-magnetic layer. The lower magnetic layer, the coil and the upper magnetic layer are laminated on the non-magnetic layer such that the upper and lower magnetic layers constitute a closed magnetic path, and such that a magnetic gap is formed between the upper and lower magnetic layers and is open in a top face of each air bearing portion.

Thin-film magnetic head having slider body formed of ferrite

Core chip for magnetic head core slider, having marker indicating

A core slider for a rigid magnetic disk drive, including a slider body having air bearing portions, and a core chip which has a magnetic gap for writing and reading information and which is integrally secured to the slider body. The slider body consists of a ferrite section which includes at least the air bearing portions and which is formed of Mn-Zn ferrite, and a non-magnetic ceramic section formed of a non-magnetic ceramic material. The core chip is accommodated in a groove formed in the slider body and bonded to the slider body by a glass material.

Core slider for rigid magnetic disc drive

A composite magnetic head core with a writing/reading track and two erasing tracks, including a first ferrite block, and a second and a third ferrite block bonded to opposite surfaces of the first block interposed therebetween. The opposite abutting surfaces of the first block have respective first and second recessed portions, and a first rectangular protrusion and two second rectangular protrusions which protrude from the first and second recessed portions, respectively. The first protrusion is positioned between the two second protrusions in a direction of width of the writing/reading and erasing tracks. The first protrusion cooperates with the second block, to define a writing/reading magnetic gap of the writing/reading track, while the second protrusions cooperate with the third block, to define two erasing magnetic gaps of the erasing tracks. The first protrusion has a width defining the width of the writing/reading track, and a longitudinal end defining a depth of the writing/reading magnetic gap. Similarly, each second protrusion has a width defining the width of the erasing tracks, and a longitudinal end defining a depth of the erasing magnetic gaps. The protrusions are formed by etching the opposite surfaces of the first block through appropriate etching masks.

Magnetic head core

A head core slider for a rigid magnetic disk drive, including a slider body, a track portion, a yoke portion and a narrow stepped portion. The slider body has two spaced-apart parallel air bearing portions, and the track portion is formed integrally with at least one of the bearing portions, so as to extend from one end of the bearing portion in the direction of length of the bearing portion. The track portion has the same height as the bearing portion, and a width smaller than that of the bearing portion. The yoke portion is formed integrally with the track portion, so as to extend from one end of the track portion remote from the bearing portion, and has a protrusion of the same height as the track portion. The width of the protrusion is smaller than that of the bearing portion and larger than that of the track portion. The stepped portion is formed so as to surround at least the track portion and the protrusion of the yoke portion, and has a surface which is spaced apart from top surfaces of the track portion and the protrusion by a distance nearly equal to the predetermined height. The bearing, track and stepped portions and the protrusion are formed by etching the surfaces of two bonded ferrite blocks, through an etching mask pattern corresponding to the desired configuration to be formed.

Head core slider having an air bearing surface of a particular

A method of producing a composite type magnetic head core, WHEREIN a first and a second ferrite block are joined together into an integral ferrite structure, such that a metallic magnetic film is interposed between opposite portions of joining surfaces of the two ferrite blocks which define a magnetic gap open in a track portion provided by the ferrite blocks, and said integral ferrite structure is cut to shape a yoke portion which includes at least a part of the track portion. Said metallic magnetic film, said track portion and said yoke portion having a first, a second and a third width as measured in a direction parallel to said magnetic gap, respectively, characterized in that: Before the two ferrite blocks are bonded together at the joining surfaces, the metallic magnetic film is formed on at least one of the opposite portions of the joining surfaces, such that the width of the film is no less than the width of the track portion, and is no more than the width of the yoke portion.

Method of producing composite type, metal-in-gap magnetic head core

A magnetic head core including two ferrite blocks which are bonded together so as to form a magnetic path and which includes respective two protrusions protruding from the opposed surfaces thereof. The protrusions have opposed end faces cooperating with each other to define a magnetic gap therebetween. The opposed surfaces of the two ferrite blocks cooperate with the two protrusions, to define two cutouts formed on opposite sides of the magnetic gap, such that a spacing provided between the opposed surfaces by each cutout is larger than an amount of the magnetic gap. The cutouts define an effective width of a track of the head core in which the magnetic gap is open. Each protrusion has two side surfaces inclined at an angle of 25.degree.-75.degree. with respect to its end face. Each cutout is defined by at least one pair of opposed ridges which are formed on the opposed surfaces of the two ferrite blocks, respectively, such that each ridge is disposed on each side of a corresponding one of the two protrusions.

Magnetic head core with special gap structure

Method for producing a head core slider for a rigid magnetic disk drive, including a ferrite slider body having a pair of air bearing portions which have a predetermined height and are spaced apart from each other in a transverse direction perpendicular to a direction of extension thereof, and further including a pair of ferrite yoke portions formed integrally with the slider body. The yoke portions cooperate with the slider body to form a first and a second closed magnetic path and define therebetween a first and a second magnetic gap. The slider body and the yoke portions cooperate to provide a first and a second track portion in which the first and second magnetic gaps are open, respectively. The first and second track portions have sliding surfaces which have the same height as the air bearing portions. The first track portion is used exclusively for an information writing operation, while the second track portion is used exclusively for an information reading operation. Where the first and second track portions have a same width, the first and second magnetic gaps have different sizes. Where the two magnetic gaps have a same size, the two track portions have different widths. Alternatively, the two track portions have different widths while the two magnetic gaps have different sizes.

Growing community of inventors

Kasugai, Japan

Nobuhiro Terada