Nissan Motor Company Limited

Other

Daido Tokushuko Kabushiki Kaisha

Daido Steel Co., Ltd.

Horoshi Yamamoto

Munekatsu Shimada

Hideaki Ono

Makoto Kano

Tetsurou Tayu

Takae Ono, Legal Representative

Yoshio Kawashita

Norihisa Waki

Shinichiro Kitada

Toshio Kikuchi

Hiroyuki Aoki

Masashi Mizuno

Toshimitsu Matsuoka

Hiroshi Yamamoto

Hiroshi Sakurai

Yutaro Kaneko

Akira Fujiki

Ryoji Nakayama

Itaru Shibata

Shinichiro Yahagi

Katsuhiro Kojima

Takanobu Saito

Mikiya Shinohara

Kimihiro Shibata

Masaaki Katsumata

Mitsuo Uchiyama

Yu Owada

Masaru Nagata

Tatsuo Sugiyama

Takeshi Yamauchi

Katsuhiko Mori

Kiyohiro Uramoto

Masao Aihara

Naoshi Sakata

Takahiko Iriyama

Yuu Oowada

Mitsuaki Fujita

Masaharu Ooshima

Yoji Ozawa

Shigeo Hanashima

Nobuyuki Matsui

A magnetostrictive stress sensor () includes: a magnetic member {, ()} having a magnetostriction; a permanent magnet () adjacent to the magnetic member; a magnetic sensor (A,B) for detecting a leak magnetic flux on a side opposite to the permanent magnet with respect to the magnetic member, wherein the leak magnetic flux changes according to a stress acting on the magnetic member and the magnetic sensor detects the change of the leak magnetic flux, to thereby detect the stress acting on the magnetic member, and a direction (A,A) of the stress acting on the magnetic member is substantially orthogonal to a magnetizing direction (A) of the permanent magnet.

Magnetostrictive stress sensor

A rare earth magnet powder has a chemical composition which includes R: 5 to 20% (wherein, R represents one or two or more rare earth elements being inclusive of Y but exclusive of Dy and Tb), one or two of Dy and Tb: 0.01 to 10%, and B: 3 to 20%, with the balance comprising Fe and inevitable impurities; and an average particle diameter of 10 to 1,000 &#x3bc;m, wherein 70% or more of the entire surface of the rare earth magnet powder is covered with a layer being rich in the content of one or two of Dy and Tb and having a thickness of 0.05 to 50 &#x3bc;m.

Rare earth magnet powder and method of producing the same

A rare earth magnet includes rare earth magnet particles; and amorphous and/or crystalline terbium oxide present at the boundary of the rare earth magnet particles and represented by the formula: TbO, wherein 1.5&#x3c;n&#x2266;2. The rare earth magnet prevents decrease eddy current effectively.

Rare earth magnet and method therefor

A Nd&#x2014;Fe&#x2014;B type anisotropic exchange spring magnet is produced by a method of obtaining powder of a Nd&#x2014;Fe&#x2014;B type rare earth magnet alloy which comprises hard magnetic phases and soft magnetic phases wherein a minimum width of the soft magnetic phases is smaller than or equal to 1 &#x3bc;m and a minimum distance between the soft magnetic phases is greater than or equal to 0.1 &#x3bc;m, obtaining a compressed powder body by compressing the powder, and obtaining the Nd&#x2014;Fe&#x2014;B type anisotropic exchange spring magnet by sintering the compressed powder body using a discharge plasma sintering unit.

Nd-Fe-B type anisotropic exchange spring magnet and method of producing the same

An anisotropic exchange spring magnet powder complexing a hard magnetic material and a soft magnetic material, wherein a rare earth metal element, a transition metal element, boron and carbon and the like are contained, and the hard magnetic material and soft magnetic material have crystal particle diameters of 150 nm or less. A method of producing an anisotropic exchange spring magnet powder comprises treating a crystalline mother material containing a hard magnetic material and soft magnetic material or the crystalline mother material having amorphous parts, in a continuous process composed of an amorphising process and the following crystallizing process, repeated once or more times. An anisotropic exchange spring magnet is obtained by treatment, in an anisotropy- imparting molding process and a solidification process, of an anisotropic exchange spring magnet powder.

Exchange spring magnet powder and a method of producing the same

The present invention provides a rare earth magnet superior in magnetic properties and thermal stability. In an aspect of the present invention, a production method of an alloy thin ribbon for a rare earth magnet includes a step to obtain a quenched thin ribbon by feeding a molten alloy containing praseodymium (Pr), iron (Fe), cobalt (Co), titanium (Ti), boron (B), and silicon (Si) on a rotating roll and a step to apply heat treatment to the quenched thin ribbon at a heating rate within a range of 100&#xb0; to 150&#xb0; C./min to crystallize the quenched thin ribbon.

Alloy thin ribbon for rare earth magnet, production method of the same, and alloy for rare earth magnet

A rare earth magnet comprises rare earth magnet particles and a rare earth oxide being present between the rare earth magnet particles. The rare earth oxide is represented by a following general formula (I):RO&#x2003;&#x2003;(I)

Rare earth magnet, method for manufacturing the same, and motor using rare earth magnet

An exchange-spring magnet is prepared using a magnet alloy containing Ta and C in addition to Nd, Fe and B. This exchange-spring magnet uses the magnet alloy prepared by a liquid quenching method or a mechanical alloying method. Further, by subjecting the magnetic alloy having a part set in an amorphous state to heat treatment, an exchange-spring magnet exhibits good properties regarding magnetic flux density and coercive force.

Magnet containing low rare earth element and method for manufacturing the same

A rare earth magnet to be used in a motor. The rare earth magnet comprises rare earth magnet particles. Additionally, a rare earth oxide is present among the rare earth magnet particles, the rare earth oxide being represented by the following general formula (I):RR'O&#x2003;&#x2003;(I)where each of R and R&#x2032; is one element selected from the group consisting of yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb) and lutetium (Lu), and 0&#x3c;x&#x3c;1.

Rare earth magnet, process for producing same, and motor using rare earth magnet

An electrical-steel-sheet formed body is provided with an opening portion into which a permanent magnet is inserted, and an outer-peripheral hardened portion formed on the electrical-steel-sheet formed body at an outer periphery side thereof for the opening portion and having a higher hardness than a remaining area of the electrical-steel-sheet formed body. The electrical-steel-sheet formed body can be used as the rotor of the built-in permanent magnet type rotary electric machine, and the built-in permanent magnet type rotary electric machine can be obtained.

Electrical-steel-sheet formed body for rotor core, rotor, rotary electric machine and related method

A Nd&mdash;Fe&mdash;B type rare earth magnet alloy is provided with hard magnetic phases each of which has a size equal to or less than 80 nm, soft magnetic phases each of which has a size equal to or less than 80 nm, with the hard and soft magnetic phases being present in a mixed structure, and partly anisotropic regions wherein axes of easy magnetization of the hard magnetic phases are aligned in one direction and each having a size equal to or greater than 0.1 &mgr;m. Such a magnet alloy is obtained using a strip casting method or ultra cooling method and serves as material for an anisotropic exchange spring magnet to be applied to a motor.

Rare earth magnet alloy, manufacturing method thereof and product applied with rare earth magnet alloy

A bulk exchange-spring magnet , a method of producing the same, and a device incorporating the bulk exchange-spring magnet are disclosed. The magnet includes magnet powders having hard and soft phases, and boron and oxygen atoms which cohere in boundary areas between grains of the densified magnet powders . In a production method, the magnet powders are compacted so as to incorporate boron and oxygen atoms into the boundary areas and are heated under a compacted state of the magnet powders at varying operating temperatures for a given time period. This results in formation of a highly densified magnet at a lower potential operating temperature for a shorter time period without the grain growth. The device includes the bulk exchange-spring magnet containing the boron and oxygen atoms cohering between the grains of the densified magnet powders.

Bulk exchange-spring magnet, device using the same, and method of producing the same

A rotor structure for a permanent-magnet motor is disclosed as including an annular laminated stack ( ) of electromagnetic steel sheets incorporating magnets, annular end plates ( ) located at both ends of the annular laminated stack to hold the same, a cylindrical core buck ( ) carrying thereon the annular laminated stack and the annular end plates, and a rotor shaft ( ) integrally connected to the cylindrical core buck for rotating movement. The annular laminated stack has a plurality of first fixing portions ( &Prime;), and each of the annular end plates has a plurality of second fixing portions ( &Prime;) which are held in engagement with the first fixing portions of the annular laminated stack, with the annular end plates and the annular laminated stack being fixed to one another by caulking at the first and second fixing portions.

Rotor structure for permanent-magnet motor

This invention relates to an anisotropic magnet having excellent magnetic characteristics such as a high magnetic flux density, a process for producing the same, and a motor having the same.

Anisotropic magnet and process of producing the same

A rotor ( ) for a synchronous motor is provided with a plurality of magnets ( ) being substantially V-shaped in cross-section. The V-shaped cross-section is defined by an inner V-surface ( ), an outer V-surface ( ) and an outward face ( ) facing outwardly. A first angle &agr; is subtended between a first straight line connecting a point of intersection ( ) of the outer V-surface ( ) and the outward face ( ) and a second straight line connecting the center ( ) of the rotor ( ) and the acute angle point ( ). A second angle &bgr; is subtended between the first straight line and a third straight line connecting a point of intersection ( ) of the inner V-surface ( ) and the outward face ( ). By setting the angle &bgr; to be larger than percent of the angle &agr;, leakage flux at both ends of the magnets ( ) is reduced.

Rotor for synchronous motor

Growing community of inventors

Tokyo, Japan

Munekatsu Shimada