Hitachi, Ltd.

Hitachi Automotive Engineering Co., Ltd.

Hitachi Global Storage Technologies Netherlands B.v.

Hitachi Car Engineering Co., Ltd.

Yukio Kato

Irizo Naniwa

Atsuo Hotta

Shinya Igarashi

Takuya Matsumoto

Mikio Tokuyama

Hiroshi Hirayama

Yoshihiro Shiroishi

Hiromitsu Tokisue

Junguo Xu

Chihiro Kobayashi

Mitsukuni Tsutsui

Masaru Furukawa

Teruo Isobe

Shigeo Nakamura

Yoshinori Takeuchi

Masaaki Matsumoto

Yotsuo Yahisa

Tomoo Yamamoto

Shuji Imazeki

Akira Ishikawa

Junichi Matsuno

Takayuki Nakakawaji

Tetsuya Hamaguchi

Hiromu Kikawa

Sadao Hishiyama

Tomoyuki Ohno

Akira Takasago

Nobuo Nakagawa

A magnetic head slider inspection device including a motor unit for revolving a disk medium, a slider unit provided with a reproducing head, which is levitated from a surface of the disk medium under force generated by the revolving disk medium, a magnetic field generator positioned at an opposite side of the disk medium with respect to the slider unit for generating a magnetic field substantially perpendicular to the disk medium surface, and a circuit unit for generating the magnetic field from the magnetic field generator, and measuring a resistance value of the reproducing head levitated from the disk medium surface.

Magnetic head slider inspection device

There is provided a thermally assisted magnetic recording device capable of preventing collision between a thermally assisted magnetic recording head and a disk due to thermal deformation of a near-field transducer. The thermally assisted magnetic recording device includes a temperature sensor for measuring the temperature in the vicinity of the near-field transducer, a table that stores the relationship between temperature and deformation in the vicinity of the near-field transducer, and a control unit. The control unit calculates the deformation in the vicinity of the near-field transducer, from the temperature measured by the temperature sensor and the relationship between temperature and deformation stored in the table. Then, the control unit drives the flying height control actuator according to the calculated deformation to control the distance between the thermally assisted magnetic recording and the disk in order to avoid contact between them.

Thermally assisted magnetic recording device

A thermally assisted magnetic recording head is formed of a slider and a magnetic head. The magnetic head includes a main pole, a reader, a coil, a near-field transducer, and a waveguide. A metal film with high thermal conductivity is formed at both sides of the near-field transducer in a width direction of the magnetic head. The use of the metal film as a radiator plate ensures to prevent the temperature of the near-field transducer from becoming locally high.

Thermally assisted magnetic recording head

A hard-disk drive. The hard-disk drive includes a disk enclosure, a magnetic-recording disk accommodated in the disk enclosure, and a diffusion suppressing film. The diffusion suppressing film divides the space in the disk enclosure into a first space where the magnetic-recording disk is disposed and a second space for retaining a lubricant. The diffusion suppressing film also suppresses diffusion of the lubricant from the second space to the first space.

Hard-disk drive with vapor-phase lubricant supply system

An information recording apparatus includes a medium for recording information; a head slider including a device for writing the information onto the medium and a reflective surface for reflecting light; a light emitting portion for generating emission light toward the reflective surface; a light receiving portion for detecting light reflected on the reflective surface; and a regulating mechanism for adjusting an amount of the emission light from the light emitting portion in a mode of information recording onto the medium in correspondence to a result of the detection.

Head stack assembly and information recording apparatus

A thermally assisted magnetic head-slider includes an air-bearing slider, a metal film, and a semiconductor laser unit. The metal film having an aperture in a part through which light from the semiconductor laser unit passes is disposed between a surface opposite to an air-bearing surface of the air-bearing slider and the semiconductor laser unit, and a material to adjust refractive index is provided in the aperture. A bottom surface of the metal film including the material to adjust refractive index is disposed to be in close contact with a surface opposite to the air-bearing surface side of the air-bearing slider, and the semiconductor laser unit is disposed to be in close contact with a top surface of the metal film including the material to adjust refractive index.

Thermally assisted magnetic head-slider and head-gimbal assembly

In a thermally assisted magnetic recording head support mechanism, an increase in the temperature of a heat source for supplying an optical near-field transducer with light, due to heat generation by the heat source, is checked while holding back an increase in weight of a slider and lessening transmission loss of light. The thermally assisted magnetic recording head support mechanism is made up such that a suspensionhas one end holding a slideron which a magnetic headhaving a read element, write element, and an optical near-field transduceris mounted, and the other end of the suspensionis held by a carriage. The optical blockprovided with one light source, and an optical switching mechanism capable of switching a guidance destination of irradiated light from light sourceis attached to an armor a supportof the carriagehaving a wide heat release area, thereby guiding light from the optical blockto the optical near-field transducervia an optical waveguide

Thermally assisted magnetic recording head having movable mirror for optical switching

In a gas-flow measuring instrument for measuring a gas flow in an intake gas passage for sucking gas, an abnormal output, deterioration per hour, stain, and breakage of a flow measuring element caused by fluid and foreign materials contained in intake gas are reduced. A gas-flow measuring instrument disposed in an intake gas passage for sucking gas for measuring a gas flow includes a bypass passage for bringing gas flowing along the intake gas passage, a bypass passage inlet opened to the upstream side of a main stream direction of gas in the intake gas passage, and a flow measuring element disposed in the bypass passage.

Gas-flow measuring instrument

A magnetic head support mechanism comprises: a magnetic head for writing and reading data relative to a magnetic disk; a slider having a flying surface for flying over a surface of the magnetic disk, the slider having the magnetic head mounted thereon; a mounting portion on which the slider is mounted; a transverse frame connected to one end of the mounting portion; two flexible finger portions which extend respectively from opposite ends of the transverse frame, and are disposed respectively on opposite sides of the mounting portion; a beam portion connected at one end thereof to ends of the flexible finger portions; a spring portion connected at one end thereof to the other end of the beam portion; an arm mounting portion connected to the other end of the spring portion; and a slider posture control mechanism connecting a reverse surface of the slider at an air inflow-side end thereof to the beam portion.

Magnetic head support mechanism and magnetic disk device

When a negative pressure slider is used in the magnetic head support mechanism with a loading/unloading function, the gimbals is likely to be deformed or damaged. Apart from the first tab provided to the front end of the suspension, the second tab is provided to the front end of the gimbals. In addition to the Suspension supporting ramp, the ramp portion has the second ramp for supporting the gimbals. This arrangement allows the slider mounting gimbals, in addition to the suspension, to be loaded/unloaded. Unlike the conventional drive in which only the suspension is loaded/unloaded, this arrangement enables the gimbals to be loaded/unloaded while maintaining a predetermined space between the gimbals and the suspension, thus reducing the risk of gimbals deformation and damage.

Magnetic head support mechanism and magnetic disk drive

A magnetic storage apparatus includes a substantially non-flexible magnetic recording medium, a magnetic head slider having a reading/writing element mounted therein and liquid lubricant provided on the surface of the magnetic recording medium. The liquid lubricant is a liquid in a Newtonian range having a viscosity which is substantially constant irrespective of a shear rate or a liquid having the property that the actual viscosity is increased with increase of the shear rate. The magnetic head slider maintains a gap between the slider and the magnetic recording medium to perform reading and writing while being moved on the liquid lubricant intermittently or continuously in a contact manner with the liquid lubricant. There is provided a device for maintaining a constant flying height even if a movement speed is varied, which flying height is represented by the size of the gap. Thus, the magnetic storage apparatus of the liquid bearing system or the contact system has only very small forces such as liquid drag force and friction force or sticking force and is capable of performing stable slider movement, performing high-speed seeking operation with high reliability and performing high-density recording.

Magnetic disk apparatus employing liquid bearing type or physical

An air flow rate measuring device for measuring intake air flow rate in an automotive engine, improved to reduce any error attributable to variation in the configurations of air cleaner and/or duct forming air passage upstream of the flow rate measuring device, thus offering high accuracy of the flow rate measurement. In one aspect of the invention, the inlet opening of a sub-air passage is disposed to contain the axis of a main air passage, while the outlet opening of the sub-air passage is disposed in the vicinity of a wall defining the main air passage. In order to cause a local reduction of the pressure of the principal of the air flow at the outlet opening, a protrusion or a flat surface which causes impediment to the flow if air in the main air passage is provided immediately upstream of the outlet opening. In another aspect, the inlet surface in which the inlet of the sub-air passage opens is stepped in the direction of flow of the air so as to enable air to be introduced into air flow rate measuring portion in the sub-air passage from different regions in the main air passage while giving a preselected order of preference to these different regions.

Air flow rate measuring device

A thin-film magnetic recording medium improves the magnetostatic and dynamic magnetic characteristics of the conventional magnetic recording media. In one embodiment, the substrate surface is textured in both the circumferential and radial directions. In further embodiments, a variety of underlayers (13) and crystal orientation control layers (17) are provided in accordance with specific parameters to control the crystal structure of the magnetic layer (14). Finally, an embodiment includes multiple magnetic layers (14, 19) having respectively different residual magnetic flux densities and thicknesses, but similar dot products of residual magnetic flux density and thickness.

Magnetic recording medium, method for its production, and system for its

Disclosed is a memory cell circuit including a pair of memory transistors having respective collectors and bases cross-coupled to each other, wherein load means connected to the collector of each one of said memory transistors comprises a parallel circuit of a load resistance and a transistor whose emitter and collector are connected to both ends of the load resistance and whose base is connected to the collector of the other of the memory transistors, thereby causing the readout currents of the memory cell circuit to be greater irrespective of increased load resistances.

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Sagamihara, Japan

Yukio Kato