Hitachi, Ltd.

Hitachi Automotive Systems, Ltd.

Tsukasa Taniguchi

Satoshi Kikuchi

Haruo Miura

Haruo Koharagi

Yasuo Fukushima

Miyoshi Takahashi

Hiroyuki Mikami

Fumio Jyoraku

Hideyuki Harada

Hidefumi Iwaki

Kouki Yamamoto

Masahiro Hosoya

Naohiko Takahashi

Shinichi Wakui

Masaharu Senoh

Tsunehiro Endou

Koichi Kashiwa

The purpose of the present invention is to provide a direct current motor wherein the number of coil-connecting wires that cross the outer surface of a coil end part is reduced. In a direct current motor that is provided with an armature that has a plurality of armature slots and has an armature coil that is wound so as to span two armature slots that are separated by a fixed number of armature slots, a lowermost layer of a coil end part is provided with at least four armature coils that are wound through other armature slots so as not to coincide with the wound armature coil, and a layer above the four armature coils that are wound on the bottommost layer is provided with at least four armature coils that are wound in the same manner as the four armature coils.

Direct current motor

A DC commutator motor includes a yoke, a field magnet, and an armature. A shaft is positioned on a central axis of the armature. A plurality of commutator segments is positioned in a circumferential direction of the shaft. A plurality of armature slots is formed on an outer periphery of an armature core. An upper coil is wound the number of turns Na through two armature slots, which are located apart from each other with the predetermined number of armature slots therebetween, at their opening sides. A lower coil is connected in parallel with the upper coil and wound the number of turns Nb through the two armature slots at their bottom sides. The number of turns Na is smaller than the number of turns Nb.

DC commutator motor and automobile including the same

A permanent magnet rotating electric machine has a stator provided with a plurality of windings, and a rotor in which magnets are disposed in slots formed in a rotor core along an outer circumference thereof. The rotor core is fixed on a rotary shaft rotating inside the stator, and one magnetic pole is constituted by each group of three or more of the magnets. A total angle occupied by the group of magnets constituting one magnetic pole is in the range of 150 to 165 degrees in terms of an electrical angle.

Rotor of permanent magnet rotating electric machine

In the prior art in which permanent magnets are regularly arranged over the whole circumference of a rotor core, a satisfactory magnetic flux distribution is hard to obtain, and the cogging torque and the distortion factor of the induced electromotive force waveform are large, whereby characteristics of a rotating electric machine are poor. Also, because the permanent magnets are arranged over the whole circumference, a large number of permanent magnets are required and cost reduction is difficult. A permanent magnet rotating electric-machine of the invention comprises a stator provided with a plurality of windings, and a rotor in which magnets are disposed in slots formed in a rotor core along an outer circumference thereof, the rotor core being fixed on a rotary shaft rotating inside the stator, and in which one magnetic pole is constituted by each group of three or more of the magnets. A total angle occupied by the group of magnets constituting one magnetic pole is in the range of 150 to 165 degrees in terms of an electrical angle.

A very high speed permanent magnet type electric rotating machine, in which loss generated on a rotor is small to achieve high efficiency on an air generating source even when driven by an inverter operating at a fundamental frequency of at least several hundreds of Hz and in which a reactor is inserted between the inverter and a permanent magnet type synchronous motor, and content percentages of components of harmonic current supplied to the permanent magnet type synchronous motor are adjusted such that when a content percentage of a fundamental wave is 100%, a content percentage B of a seventh order component is at most 10% and a total content percentage is made equal to or less than a certain value so as to satisfy the relationship (A<C<B) where A is a content percentage of a fifth order component, B is a content percentage of a seventh order component thereof, and C is a content percentage of a ninth order component thereof, thereby enabling realizing a very high speed permanent magnet type electric rotating machine system, in which harmonic loss of neodymium magnets as well as harmonic loss of a shaft is greatly reduced and loss of the rotor can be reduced to several hundreds of W.

Very high permanent magnet type electric rotating machine system

Provided are a super-high speed permanent magnet type synchronous motor which causes less loss in a rotor even though it is driven by an inverter adapted to be operated with a fundamental frequency around 1 kHz, and an air compressor. The air compressor having a super-high speed permanent magnet type synchronous motor which is composed of a stator in which armature windings are wound in a plurality of slots formed in a stator core, and a rotor including a shaft made of a conductive magnetic material, a conductive permanent magnet laid around the outer periphery of the shaft, and a reinforcing member made of carbon fibers and laid around the outer periphery of the permanent magnet, wherein a laminated electromagnetic steel sheet is interposed between the shaft and the permanent magnet, and the laminated electromagnetic steel sheet has a high tensile strength higher than 70 kg/mm .

Permanent magnet type synchronous motor and air compressor

In an ultra-permanent-magnet-type electric rotating machine including a stator in which a winding of armatures is wound in each of a plurality of slots of a stator core, and a rotor having permanent magnets respectively inserted into permanent-magnet-inserting holes in a magnetic steel sheet ring provided at an outer periphery of a conductive and magnetic shaft, the thickness of the stator core is 0.1 to 0.2 mm, and the magnetic steel sheet ring is made of a high-tensile-strength magnetic steel sheet had tensile strength of 80 kg/mm or more.

Growing community of inventors

Hitachi, Japan

Tsukasa Taniguchi