Hitachi, Ltd.

Seiichi Yamada

Ken Takahashi

Takashi Namekawa

Takashi Naitoh

Shingo Shirakawa

Shigehisa Motowaki

Takeo Yamazaki

Shigeru Tanaka

Yasuo Matsushita

Ryutarou Jimbou

Akira Ikegami

Satoru Ogihara

Kunihiro Maeda

Juichi Morikawa

Hiromitsu Nagae

Toshikazu Nishiyama

Kenkichi Inada

Tetuo Kosugi

Moritaka Shoji

Moritaka Syouji

Shinichi Oowada

Tadashi Kitami

Ryoo Gotoo

A ceramic resistor includes zinc oxide as a main component, and as essential components, aluminum oxide 3.0-40 mol %, magnesium oxide 2.0-40 mol %, silicon oxide 0.1-10 mol %, and at least one kind of compound 0.005-0.5 mol %, selected from a group consisting of calcium oxide, strontium oxide and barium oxide, and has a positive temperature coefficient of resistance. A neutral grounding resistor and a gas circuit breaker, each using the above-mentioned ceramic resistors, are disclosed.

Ceramic resistor, production method thereof, neutral grounding resistor

A mixture of calcinated metallic oxides are mixed with ZnO and SiO.sub.2, granulated, compacted and then sintered to form a nonlinear resistor. After sintering, the formed ZnO resistor elements are heat treated, preferably in a two-step heat treating process.

Method of fabricating non-linear resistor

A magnetic head for use in a magnetic recording and reproducing system, which head is excellent in magnetic properties, resistance to abrasion, durability and mass-producibility, comprises a pair of magnetic cores each having a substrate and a magnetic alloy film formed on the substrate, the cores being disposed in a manner such that the magnetic alloy films are opposed to and slightly spaced apart from each other, and glass bondings disposed between the magnetic alloy films to integrate the pair of magnetic cores, and a process for producing the same, and a magnetic recording and reproducing system using the magnetic head.

Magnetic head including PbO-V.sub.2 O.sub.5 -P.sub.2 O.sub.5 system

The present invention relates to a magnetic head in which a magnetic metal film comprising a Co-containing amorphous alloy and a crystallizable glass of the PbO-B.sub.2 O.sub.3 -ZnO system as a solder glass are used. The magnetic head of the present invention has about 2 times higher recording density than the conventional one as a magnetic head for floppy disks and hard disks because an amorphous alloy is used. Since a crystallizable glass is used as the glass, there can be obtained a magnetic head having a high strength and superior humidity resistance and reliability.

Magnetic head containing amorphous alloy and crystallizable glass

A magnetic head has a layer of amorphous magnetic alloy arranged to define a magnetic gap therebetween, the layer being bonded with a bonding glass having a viscosity of 10.sup.5 poises or less at a temperature by at least 50.degree. C. lower than the crystallization temperature of the amorphous magnetic alloy, a good water resistance after sintering and a low coefficient of thermal expansion such as 100.times.10.sup.-7 /.degree.C. or less. The bonding glass contains 55 to 70% by weight of V.sub.2 O.sub.5, 17 to 25% by weight of P.sub.2 O.sub.5, 3 to 20% by weight of Sb.sub.2 O.sub.3, 0 to 20% by weight of PbO, 0 to 15% by weight of Tl.sub.2 O, and 0 to 5% by weight of Nb.sub.2 O.sub.5.

Magnetic head having layers of amorphous magnetic alloy bonded together

An ignition distributor for an internal combustion engine with reduced electric discharge energy and suppressed radio noise generation comprises a rotor electrode capable of rotary motion and a plurality of stationary electrodes arranged substantially in a circle around the rotor electrode through an electric discharge clearance therebetween, where the rotor electrode is made of a sintered mixture comprising zirconium oxide and an electroconductive inorganic compound having a specific resistance of not more than 10.sup.6 .OMEGA.cm as main components. The sintered mixture can be ZrO.sub.2 and an oxide selected from ZnO, NiO and CoO; or ZrO.sub.2, aluminum oxide and an oxide selected from ZnO, CoO, Al.sub.2 TiO.sub.5 and SrTiO.sub.3 or a carbide selected from ZrC, TiC and TaC.

Ignition distributor for internal combustion engine

An ignition distributor for an internal combustion engine with reduced electric discharge energy and suppressed radio noise generation comprises a rotor electrode capable of rotary motion and a plurality of stationary electrodes arranged substantially in a circle around the rotor electrode through an electric discharge clearance therebetween, where the rotor electrode is a sintered mixture comprising an aluminum compound and/or a boron compound and silicon carbide and having a specific resistance of 10 to 10.sup.6 .OMEGA.cm at room temperature.

Growing community of inventors

Ibaraki, Japan

Seiichi Yamada