Sumitomo Electric Industries, Limited

Itami Works of Sumitomo Electric Industries, Ltd.

Denso Corporation

Sumitomo Electric Sintered Alloy, Ltd.

Toyota Jidosha Kabushiki Kaisha

Agency of Industrial Science and Technology

Takao Nishioka

Akira Yamakawa

Kenji Matsunuma

Takehisa Yamamoto

Masaya Miyake

Haruhisa Toyoda

Kazuhiro Hirose

Hitoshi Oyama

Matsuo Higuchi

Naoto Igarashi

Masamichi Yamagiwa

Hisao Takeuchi

Yasushi Mochida

Takashi Matsuura

Yoshishige Takano

Hirokazu Kugai

Toru Maeda

Takatoshi Takikawa

Yoshiyuki Shimada

Yasushi Ito

Akira Kuibira

Kouichi Sogabe

Koichi Sogabe

Masaaki Honda

Hirohiko Nakata

Masashi Yoshimura

Atsushi Sato

Nozomu Kawabe

Ryoji Mizutani

Tomoyuki Awazu

Tomoyuki Ueno

Osamu Komura

Yasuhiro Endo

Kazutaka Tatematsu

Kaoru Murabe

Toshihiko Kaji

Hisanori Ohara

Hiromu Izumida

Kenji Harada

Harutoshi Ukegawa

Tsuyoshi Akao

Fumihiro Wakai

Takeshi Satoh

Koji Mimura

Kenya Motoyoshi

Terukazu Tokuoka

Nobuya Oooka

Tomoyuki Awatsu

Naoki Kondoh

Yoshihiro Obata

Kouhei Sawada

Igarashi Naoto

There are provided a dust core in which, even if the surface of a heat-treated compact is ground, the insulation between soft magnetic particles on the ground surface can be ensured in the grinding step, and a method for producing the dust core. The method includes a preparation step of preparing a heat-treated compactby compacting soft magnetic particles having an insulation coating and heating the resultant compact to a predetermined temperature; and a machining step of removing part of the heat-treated compactusing a working tool. The machining step is performed while an electric current is supplied with a conductive fluidL between the heat-treated compactserving as an anode and a working toolthat machines the heat-treated compactor a first counter electrodethat faces the working toolwith a distance therebetween, the working toolor the first counter electrodeserving as a cathode. A bridge portion that connects soft magnetic particles to each other is removed through the supply of an electric current, the soft magnetic particles being adjacent to each other along a machined surface of the heat-treated compact

Dust core and method for producing the same

A soft magnetic material includes a plurality of composite magnetic particles including a metal magnetic particle and an insulating film surrounding a surface of the metal magnetic particle. The insulating film also contains a phosphate. The soft magnetic material further includes an aromatic polyetherketone resin and a metallic soap and/or an inorganic lubricant having a hexagonal crystal structure. The metallic soap and the inorganic lubricant are particles with an average particle size of not more than 2.0 &#x3bc;m.

Soft magnetic material and dust core

A soft magnetic material includes: a plurality of composite magnetic particles formed from a metal magnetic particle and an insulative coating surrounding a surface of the metal magnetic particle and containing metallic salt phosphate and/or oxide; and a lubricant formed as fine particles added at a proportion of at least 0.001 percent by mass and no more than 0.1 percent by mass relative to the plurality of composite magnetic particles. With this structure, superior lubrication is provided during compacting and desired magnetic characteristics can be obtained after compacting.

Soft magnetic material and powder magnetic core

A soft magnetic material includes a plurality of composite magnetic particles each including a metal magnetic particle and an insulating coating film covering the metal magnetic particle. Each of the plurality of composite magnetic particles has a ratio Rof a maximum diameter to a circle-equivalent diameter of more than 1.15 and not more than 1.35. The insulating coating film is composed of a thermosetting organic material and has a pencil hardness of 5H or higher after thermosetting. With this material, an eddy current loss can be reduced, and a compact with a high strength can be formed.

Soft magnetic material and dust core produced therefrom

A method for producing a dust core compact includes the steps of forming a compact component by pressure-forming a soft magnetic powder having an average particle diameter Da under a pressure Pa, and forming a compact by pressure-forming a soft magnetic powder having an average particle diameter Db and the compact component under a pressure Pb. Average particle diameters Da and Db of the soft magnetic powders satisfy relationship Da/Db&#x2267;2, and pressures Pa and Pb applied during the pressure-forming satisfy relationship Pa/Pb&#x2266;&#xbd;. With this structure, a method for producing a dust core compact exhibiting a high strength and capable of being fabricated even when it has a complex shape, and the dust core compact can be provided.

Method for producing dust core compact and dust core compact

The object of the present invention is to provide a powder core and method for making the same that is equipped with insulative coating having superior heat resistance, with the coating making it possible to adequately restrict the flow of eddy currents between particles. The powder core is equipped with a plurality of compound magnetic particles bonded to each other. Each of said plurality of composite magnetic particles includes: a metal magnetic particle; an insulative lower layer coatingsurrounding a surfaceof said metal magnetic particle; an upper layer coatingsurrounding said lower layer coatingand containing silicon; and dispersed particlescontaining a metal oxide compound and disposed in said lower layer coatingand/or said upper layer coating. A mean particle diameter R of the dispersed particlesmeets the condition 10 nm&#x3c;R&#x2266;2 T, where the average thickness of the coating combining the lower layer coatingand the upper layer coatingis T.

Dust core with specific relationship between particle diameter and coating thickness, and method for producing same

A soft magnetic material has an iron based powder that has an insulating coating on the surface and an ester wax. The ester wax is added in an amount not less than 0.02% by weight and not more than 0.6% by weight in relation to the soft magnetic material. Consequently, seizure between a metal mold and a material to be molded at the time of molding can be suppressed and the arising of a black residue can be prevented.

Soft magnetic material, compressed powder magnetic core and method for producing compressed power magnetic core

A soft magnetic material used for producing a powder compact has a plurality of iron particles having a Vickers hardness HV of less than 800 and satisfying the relationship of &#x3b1;/&#x3b2;&#x2267;2.5, where &#x3b1; represents the specific surface area of the iron particles measured by a gas adsorption method (Brunauer-Emmett-Teller (BET) method) and &#x3b2; represents the apparent specific surface area of the iron particles calculated from the average particle diameter measured by a laser diffraction/scattering method.

Soft magnetic material and method of producing powder compact

A method for making soft magnetic material includes: a first heat treatment step applying a temperature of at least 400 deg C. and less than 900 deg C. to metal magnetic particles; a step for forming a plurality of compound magnetic particles in which said metal magnetic particles are surrounded by insulation film; and a step for forming a shaped body by compacting a plurality of compound magnetic particles. This provides a method for making soft magnetic material that provides desired magnetic properties.

Process for producing soft magnetism material, soft magnetism material and powder magnetic core

The present invention provides a soft magnetic material and a powder magnetic core having desired magnetic characteristics. A soft magnetic material contains a metal magnetic powder. The metal magnetic powderis formed from crystalswith an average size, as determined from X-ray diffraction, of at least 30 nm. It would be preferable, in the metal magnetic particles, for crystal grainsto have an average size of at least 10 microns.

Soft magnetism material and powder magnetic core

A compound magnetic material having high heat resistance is provided. A fabrication method of a compound magnetic material includes the step of preparing mixed powder including an organic resin and compound magnetic particles. The long-period heat resistance temperature of the organic resin is at least 200&#xb0; C. The containing ratio of the organic resin to the compound magnetic particles exceeds 0 mass % and not more than 0.2 mass %. The compound magnetic particle includes a metal magnetic particles, and a coat layer containing metal oxide, directly bound to the surface of the metal magnetic particle. The fabrication method of a compound magnetic material includes the steps of forming a compact by introducing mixed powder into a die having a lubricant applied to its surface and conducting warm-compacting, and applying heat treatment to the compact.

Compound magnetic material and fabrication method thereof

To lighten the weight of an electromagnetic actuator and a valve-open-close mechanism by forming the stems from a lighter material than conventional. A pair of electromagnets formed of stators and coils are opposed to each other with a gap therebetween. An armature is disposed in the gap so as to be reciprocable between one electromagnet and the other electromagnet by the electromagnets. A first stem for transmitting the movement of the armature from one electromagnet toward the other electromagnet to a valve of the internal combustion engine is inserted in a guide hole formed in the stator of one electromagnet. The first stem is formed of a lighter material than the armature to lighten the weight of the electromagnetic actuator and a valve-open-close mechanism of an internal combustion engine.

Electromagnetic actuator and valve-open-close mechanism

Provided is a diamond-coated sliding part that is light, has excellent abrasion resistance, that prevents abrasion of the material of an opposite member, and that is effective in reducing power loss. This sliding part is especially useful as an adjusting shim for the valve train mechanism of an internal combustion engine such as an automobile engine in which the base material is silicon nitride or sialon and this base material surface is coated with a diamond coating layer. By performing finish processing on only a small part of peaks of diamond particles protruding from the surface of the diamond coating layer to reduce the height of the protrusions, or by controlling film forming conditions, etc., the profile bearing length ratio (t ) at a cutting level of 0.1 &mgr;m for the sliding surface of the diamond coating layer is made 60% or greater.

Diamond-coated sliding part

An electromagnetic actuator for an automotive internal combustion engine is provided which has a stator, the weight of which is reduced. The electromagnetic actuator has a pair of electromagnets each made up of a stator and a coil, an armature disposed between the pair of electromagnets so as to be reciprocable therebetween, and a first stem provided on one side of the armature for transmitting the movement of the armature to external. The stator is formed by powder molding.

Electromagnetic actuator

It is proposed to lessen the weight and improve the mechanical strength of a retainer of a valve open-close mechanism driven by an electromagnetic actuator used in an automotive internal combustion engine. The electromagnetic actuator is mounted in a housing mounted on an internal combustion engine body. A first stem has its tip abutting the valve, which is provided with a retainer and carries a first coil spring. A second stem is provided on the other side of an armature. The second stem has a retainer. Between this retainer and the housing, a second coil spring is mounted. At least one of these parts is made of a metal smaller in specific weight than iron or its alloy. Each retainer has a boss and an arcuate corner portion having a radius of curvature R of 1.0 mm or over between a spring abutting surface and the boss to relieve stress concentration.

Valve-open-close mechanism

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Itami, Japan

Takao Nishioka