Hitachi, Ltd.

Hitachi Appliances, Inc

Hitachi Metals, Ltd.

Hitachi Industrial Equipment Systems Co., Ltd.

Japan Servo Co.,ltd.

Hitachi Powdered Metals Co., Ltd.

Hitachi Setsubi Engineering Co., Ltd.

Haruo Koharagi

Satoshi Kikuchi

Kazuo Tahara

Miyoshi Takahashi

Yoshitaro Ishii

Kunio Miyashita

Fumio Jyoraku

Hisanori Toyoshima

Tsunehiro Endo

Syuji Watanabe

Shinichi Wakui

Masaharu Senoh

Wakichiro Hishi

Kouki Yamamoto

Koujirou Yamashita

Keiji Noma

Kohichi Saito

Ryoichi Takahata

Tomio Yoshikawa

Akeshi Takahashi

Kazuo Sato

Haruo Miura

Noriyoshi Takahashi

Yasuo Fukushima

Shigekazu Nozawa

Takayuki Matsui

Tsukasa Taniguchi

Baiying Huang

Hisao Suka

Kohei Ishii

Hiroshi Hirayama

Yuji Enomoto

Takeshi Abe

Kenji Tojo

Toshiyuki Ajima

Mamoru Kimura

Takeshi Tsuchiya

Mutsunori Matsunaga

Hirokatsu Kohsokabe

Hiroyuki Mikami

Yuuichi Yanagase

Tunehiro Endo

Shigeya Kawaminami

Kazuyuki Fujimura

Hisaya Sasamoto

Mitsuhisa Kawamata

Atusi Hosokawa

Takashi Seshimo

Ryoso Masaki

Motoo Futami

Matahiro Komuro

Yuichi Satsu

Masahiro Mita

Kazumasa Ide

Motoya Ito

Chio Ishihara

Naohiko Takahashi

Shoji Ohiwa

Seizi Yamashita

Yasuomi Yagi

Tadashi Fukushima

Kouichi Saito

Shoichi Ito

Seiji Yamashita

Yasuro Ohishi

Tsunehiro Endou

Kado Miyakawa

Mitsuhiro Nitobe

Nobutaka Suzuki

Fumio Jyouraku

Katsuyuki Yamasaki

Baiying Hang

Akira Takemura

Susumu Nakayaka

A permanent magnet type electric rotating machine having a high resistance permanent magnet used for the electric rotating machine, the permanent magnet containing a magnetic powder and a fluorine compound, in which the current waveform is controlled for reducing the loss to satisfy a relation: A&#x3c;C&#x3c;B and restrict the 7th higher-harmonic component to 20% or less where A is the content for the 5th higher harmonic component, B is the content for the 7th higher harmonic component, and C is the content for the 11th higher harmonic component, assuming the total of contents for the fundamental components of a current supplied to the findings being 100%.

Permanent magnet type electric rotating machine

In order to make a displacement type compressor be able to reliably start without increasing an outside diameter dimension of the compressor while using a self-start synchronous motor having high energy efficiency, the displacement type compressor according to the invention includes the self-start synchronous motor which starts as an induction-motor and performs synchronous operation by performing synchronization pull-in almost at a synchronous rotational frequency, a compression part having a compression chamber which compresses a working fluid, and a hermetic container which houses the self-start synchronous motor and the compression part. The displacement type compressor is provided with a start load reducing means which reduces a load of the compression part at startup and is placed at the compression part in the hermetic container.

Displacement type compressor having a self-start synchronous motor and start load reducing means

The inventive self-initiated permanent magnet synchronous motor has a rotor that has two-pole permanent magnets, as well as magnetic substances in a peripheral direction between the magnetic poles of the permanent magnets. The present invention provides a high-efficiency, high-torque permanent magnet synchronous motor with an improved power factor, its rotor, and a compressor using the permanent magnet synchronous motor, without a reduction in the maximum torque and an increase in costs.

Permanent magnet synchronous motor, rotor of the same, and compressor using the same

An electric rotating machine having permanent magnets having a rotor having a plurality of permanent magnets, a stator iron core disposed in opposite relation with the rotor, and a stator winding wound around the stator core, wherein the stator core is constituted by a yoke and a plurality of teeth portions disposed to the yoke. The teeth portions are projected towards the inner periphery of the rotor. The teeth portions are made of amorphous magnetic material.

Electric rotating machine having permanent magnets and method of manufacturing teeth portions of the stator iron core

In a method of manufacturing a self-start synchronous motor for preventing deterioration of permanent magnets used in a rotor, and also for enhancing the efficiency of the self-start synchronous motor, the self-start synchronous motor comprising a stator having a stator core and windings wound around the stator core, and a rotor having an outer diameter slightly smaller than an inner diameter of the stator and arranged inside of the stator. The rotor is provided with a rotor core, a plurality of conductor bars embedded in the outer peripheral portion of the rotor core over an entire periphery thereof, end rings provided on opposite end sides of the conductor bars and constituting a squirrel cage conductor in cooperation with the conductor bars, and a plurality of permanent magnets embedded in the rotor core and arranged at a position inner than that of an inner peripheral surface of the conductor bars. Further, the conductor bars and the end rings are electrically and mechanically joined together through frictional agitation joint.

Self-start synchronous motor with permanent magnets and at least one frictional agitation joint, method for manufacturing the same and compressor comprising the same

The invention provides a motor comprising a stator and a rotor. The stator core includes a laminated stator core made of laminated stator core plates in which straight cut surfaces are formed on a circular outer peripheral surface of the laminated stator core plates. The straight cut surfaces of the laminated stator core plates are circumferentially displaced every predetermined laminated stator core plates so that the straight cut surfaces are uniformly distributed in an axial and a circumferential direction of the laminated stator core. Therefore, a flow passage for lubricating oil is ensured, while local magnetic saturation of the stator core is dissolved and a cogging torque and an induced voltage waveform distortion rate are improved.

Motor, compressor, and air conditioner

A permanent magnet synchronous motor includes a rotor having cage windings and permanent magnets placed on an inner peripheral side of these cage winding bars, where the permanent magnets are placed and polarized so that a ratio &#x3b8;/&#x3b1; between a circumferential pitch angle &#x3b8; of magnetic flux distribution of the permanent magnets and a magnet pole pitch angle &#x3b1; is between 0.67 and 0.91.

Permanent magnet synchronous motor and compressor using the same

In order to make a displacement type compressor be able to reliably start without increasing an outside diameter dimension of the compressor while using a self-start synchronous motor having high energy efficiency, the displacement type compressor according to the invention includes the self-start synchronous motor which starts as an induction-motor and performs synchronous operation by performing synchronization pull-in almost at a synchronous rotational frequency, a compression part having a compression chamber which compresses a working fluid, and a hermetic container which houses the self-start synchronous motor and the compression part. The displacement type compressor is provided with a start load reducing means which reduces a load of the compression part at startup and is-placed at the compression part in the hermetic container.

An air conditioner comprising a compressor including a compression unit and a permanent magnet rotating electric machine, wherein the permanent magnet rotating electric machine includes a stator, into which concentratively wound armature windings are inserted in such a way as to surround a plurality of teeth formed in a stator core, and a rotor having permanent magnets accommodated into a plurality of permanent magnet inserting holes formed in a rotor core. Each pair of adjacent ones of said permanent magnets is arranged generally in one of a convex V-shaped configuration and a convex U-shaped configuration with respect to a rotor axis, and a substantially V-shaped recess portion is formed between adjacent poles in outer circumferential surface portions of the rotor core.

Air conditioner having permanent magnet rotating electric machine

In a permanent magnet type rotating electric machine comprising a stator of which concentratedly wound armature windings are disposed in a plurality of slots formed in a stator core so as to surround teeth and a rotor accommodating permanent magnets in a plurality of permanent magnet insertion holes formed in a rotor core, a part of outer circumferential faces of slots is formed to extend substantially in parallel with a part of inner circumferential faces of the teeth, thereby, a permanent magnet type rotating electric machine with limited noises can be realized.

Permanent magnet type rotating electric machine

A permanent magnetic type electric rotating machine includes: a stator having armature winding arranged in several slots formed in a stator core; and a rotor having permanent magnets held in several permanent magnetic insertion holes formed in a rotor core, in which a peripheral surface of the rotor core is configured to be a combination of arcs around two points different from a center of the rotor core for each magnetic pole in such a manner that when an axis extending in a central direction of a magnetic pole of the rotor is a d axis, and an axis extending in a direction between magnetic poles that is offset from the central direction of the magnetic pole by 90 electrical degrees is a q axis, a radial distance from a center of the rotor core to a periphery of the rotor is reduced gradually from the d axis to the q axis.

A permanent magnet type rotating electrical machine characterized by reduced vibration and noise, or improved efficiency. In a permanent magnet type rotating electrical machine comprising a stator provided with concentrated winding and a rotor with permanent magnets embedded in the rotor core induced voltage waveform is improved by formation of two grooves or holes (flux barriers) extending in the axial direction for each magnetic pole on the bridge of the core between the permanent magnet insertion hole and the outer surface of rotor in such a way that they are placed at an equally spaced interval over the entire circumference of the rotor

Permanent magnet type rotating electrical machine, and power generation system and drive system using it

A permanent magnet rotating electric machine that comprises a stator, into which concentratively wound armature windings are inserted in such a way as to surround a plurality of teeth formed in a stator core, and a rotor having permanent magnets accommodated into a plurality of permanent magnet inserting holes formed in a rotor core. In this rotating electric machine, the permanent magnets are convex V-shaped or U-shaped with respect to a rotor axis. Moreover, nearly V-shaped recess portions, each of which is placed between adjacent poles, are formed in outer circumferential surface portions of the rotor core. Thus, torque caused by magnetic flux due to the magnets is increased, while armature reaction magnetic flux generated by an armature current is reduced. Consequently, q-axis inductance is reduced, so that armature current commutation is quickly achieved. Thus, the permanent magnet rotating electric machine using the stator employing concentrated windings and also using the magnet-embedded rotor is stably driven even when driven by a position sensorless inverter in the case of 120 degree energization.

Permanent magnet rotating electric machine

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Hitachi, Japan

Haruo Koharagi