Panasonic Intellectual Property Management Co., Ltd.

Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Haruhiko Kado

Akihiko Watanabe

Hirofumi Mizukami

Takehiko Hasegawa

Hiroshi Murakami

Toshiyuki Tamamura

Yuichi Yoshikawa

Kiyomi Kawamura

Hu Li

Taro Kishibe

Hisakazu Kataoka

Osaaki Morino

Yukihiro Okada

Yoshinari Asano

Noriyoshi Nishiyama

Yasufumi Ikkai

Yukio Honda

Yasushi Kato

Akihiko Yamazaki

Hiroaki Kawasaki

Shinichiro Kawano

Masayuki Shinto

Hideharu Hiwaki

Hiroshi Itoh

Noritaka Aso

Yuichiro Sadanaga

Genki Kondo

Hirfumi Mizukami

Akihako Watanabe

A motor of this invention comprises a rotor having a permanent magnet, the number of which magnet poles is P, and a stator including M pcs of teeth, the teeth arranged in a circumferential direction in a manner to face the permanent magnet through a spatial gap, wherein the stator includes stator core having the number M of the teeth, and a winding wire wound about each of the tooth, wherein the number P of the magnet poles and the number M of the teeth have a relation defined by formulae (2/3)M&#x3c;P&#x3c;(4/3)M, and M&#x2260;P, and wherein ratio (t1/Ds) of teeth tip width t1 to stator inside diameter Ds is given by a formula 0.18&#x3c;(t1/Ds)&#x3c;0.25.

Motor with rotor and stator dimensions for reducing cogging torque and torque ripple

A permanent-magnet-embedded electric motor includes a stator having a coil wound on a stator core, and a rotor disposed rotatably inside the stator through a gap to an inner circumferential surface of the stator core. The rotor is provided with a rotor core formed of laminated steel plates having a plurality of magnet-embedding holes, and a permanent magnet housed and retained in each of the magnet-embedding holes. A thickness of the bridge portions formed between edges of the magnet-embedding holes and an outer circumference of the rotor core, and a thickness of a thinned link portion connecting adjoining two of the bridge portions are thinner than a thickness of the steel plates.

Permanent-magnet-embedded electric motor and method for manufacturing same

A motor of this invention comprises a rotor having a permanent magnet, the number of which magnet poles is P, and a stator including M pcs of teeth, the teeth arranged in a circumferential direction in a manner to face the permanent magnet through a spatial gap, wherein the stator includes stator core having the number M of the teeth, and a winding wire wound about each of the tooth, wherein the number P of the magnet poles and the number M of the teeth have a relation defined by formulae (2/3)M&#x3c;P&#x3c;(4/3)M, and M&#x2260;P, and wherein ratio (t/Ds) of teeth tip width tto stator inside diameter Ds is given by a formula 0.18&#x3c;(t/Ds)&#x3c;0.25.

Motor design for reducing cogging torque and torque ripple while maintaining efficiency

A stator, a rotor, bearings, and conductive brackets are provided. The stator has a stator iron core having a winding wound thereon. The rotor has a rotating body that holds a permanent magnet in the circumferential direction so that the permanent magnet faces the stator, and a shaft that has the rotating body fastened thereto so as to penetrate through the center of the rotating body. Both of the bearing on the output shaft side and the bearing opposite the output shaft side journal the shaft. One of the brackets fixes the bearing on the output shaft side, and the other of the brackets fixes the bracket opposite the output shaft side. The brackets are electrically connected to each other, and a dielectric layer is formed between the shaft and the outer periphery of the rotating body.

Electric motor and electric device including the same

A motor includes a stator integrally molded together with a stator member, which includes a stator iron-core wound with a winding, by insulating resin, a rotor mounted on a shaft as a center and confronting the stator, two bearings supporting the shaft rotatably, brackets fixing the bearings, and a drive circuit board including a drive circuit which supplies an electric current to the winding and drives the rotor. Either one of the two bearings includes an outer ring and an inner ring both of which are electrically insulated from each other.

Electric motor and electric equipment with same

A brushless motor includes a stator molded integrally with a resin having a fixing member including a stator iron core and a winding wound thereon, a rotor of a disk-like iron core holding a ferrite resin magnet in a circumferential direction, the rotor arranged to face the stator about a shaft, a bearing rotatably supporting the shaft, and conductive brackets fixing the bearing. The brackets are electrically connected to each other with a conducting pin in the stator.

Electric motor apparatus with equi-potentialized brackets

Provided is an electric motor driven by an inverter of PWM method, and devised to retard electrolytic corrosion in a bearing. A rotating body of a rotor comprises an outer iron core configuring an outer peripheral portion of the rotating body, an inner iron core configuring an inner peripheral portion connected to a shaft, a dielectric layer disposed between the outer iron core and the inner iron core, a plurality of insertion holes penetrating the outer iron core in the axial direction, and permanent magnets inserted individually in the plurality of insertion holes. It thus becomes possible to increase impedance of the rotor side (inner ring side of bearing) to approximate it to impedance of the stator side (outer ring side of the bearing) to thereby bring high frequency potentials balanced between the inner ring side and the outer ring side of the bearing, so as to provide the electric motor that retards electrolytic corrosion liable to occur in the bearing, and an electric device equipped with the same.

Electric motor with rotating body and electric device provided therewith

A motor includes: a stator molded integrally with an insulating resin having a fixing member including a stator iron core and a winding wound thereon; a rotor arranged to face the stator about a shaft; a bearing rotatably supporting the shaft; a bracket fixing the bearing; and a drive circuit substrate having a drive circuit mounted thereon for driving the winding. The stator iron core is electrically connected to a ground serving as a reference point of a zero potential on the drive circuit substrate through a conductive member.

Brushless motor and electric device using same

A motor includes a stator having a stator iron-core on which a winding is wound, a rotor having a rotary body holding a permanent magnet opposed to the stator along a circumferential direction and a shaft joined to the rotary body such that it extends through the rotary body at the center, bearings supporting the shaft, two conductive brackets for fixing the bearings, and a printed circuit board on which a drive circuit for driving the winding is mounted. A dielectric layer is provided between an outer wall of the rotary body and the shaft, the two brackets are electrically connected together, and a capacitor is connected between the stator iron-core and the brackets for adjusting impedance.

Motor and electrical equipment equipped with same

A motor includes: a stator including a stator iron core on which a winding is wound; a rotor including a rotating body that holds a magnet in a circumferential direction to face the stator and a shaft that fastens the rotating body to penetrate a center of the rotating body; a bearing that supports the shaft; and two conductive brackets that fix the bearing. The two brackets are electrically connected to each other, and a capacitor serving as an impedance adjusting member that adjusts impedances between the stator iron core and the electrically connected two brackets is arranged.

Motor and electric device using same

A structure of a rotor used in a synchronous motor employing both of permanent magnets and a stator using concentrated windings is disclosed. Slits () provided in a section of a rotor laminated in a direction of a rotary shaft are shaped like an arc or a bow, and the shape protrudes toward an outside rim of rotor (). Permanent magnets () are inserted into slits (). This structure produces less magnetic salient poles than a conventional rotor, so that a magnetic flux density can be lowered, and an efficient motor with less loss is obtainable.

Permanent magnet synchronous motor

An electric motor is equipped with a rotor having multiple rows of slits arranged along a radial direction. A permanent magnet is buried only in some of the slits, namely the ones closest to the center of the rotor or the innermost slits, to drive the motor using both magnet torque and reluctance torque. This improves the torque output.

Electrical motor

A motor is provided that reduces vibration and noise by suppressing the vibration transmitted from a stator to a housing. Also an apparatus loaded with this motor is provided, that is highly efficient with less vibration and low noise. Notches formed at an outer circumference of a yoke are located on outer peripheral sides of slots, the notches are not in contact with the housing, the yoke located on outer circumferential sides of teeth is provided with axially penetrating through-holes, and an outer circumference of the stator core located on outer circumferential sides of the through-holes is in close contact with the housing, thus making it possible to obtain the motor with high efficiency, less vibration and low noise.

Motor

A motor and a method for manufacturing thereof use a rotor having permanent magnets and stators. The highest revolving speed of a motor is adjusted by using end plates of different thickness. The end plates are made of a magnetic material and disposed at the end faces of the rotor. The end plates made of a magnetic material provide part of the magnetic flux generated from the permanent magnets with short circuits within the inside of the rotor. The magnetic flux that links with the coil can be adjusted by using end plates of different thickness. Therefore, the highest revolving speed of a motor can be finely adjusted with ease.

Growing community of inventors

Osaka, Japan

Haruhiko Kado