Nidec Corporation

Mitsuo Kodama

Yuya Saito

Chiharu Kobayashi

Shingo Fukumoto

Toshiya Okamoto

Takashi Hattori

Yoshiaki Yamashita

Junya Mizukami

Takao Atarashi

Shunsuke Murakami

Hiroyuki Abe

Masahiro Shiraishi

Yuichi Nishikawa

Takahiro Kizu

Katsuya Takahashi

Michihiro Ito

Kazuyoshi Saito

Yuichi Shigematsu

Yoshinobu Arao

Tadashi Hasegawa

A motor includes a rotor including a shaft extending axially, a stator surrounding a radial outside of the rotor and including a coil defined by a wound coil wire, a holder disposed on an axially upper side of the stator, the coil wire being inserted into the holder, the holder including through-holes extending axially, and a circuit board disposed on the axially upper side of the holder, an electronic component being mounted on the circuit board. When the holder is viewed from the axially upper side, the through-holes are located in a region where a center angle (&#x3b1;) centered on the shaft is less than or equal to 180 degrees.

Motor and electric power steering device

A motor includes a rotor including a shaft centered on a center axis extending vertically, a stator that is radially opposed to the rotor and includes coils, a conductive holder accommodating the rotor and the stator and including a penetration unit penetrating axially, and a coil lead wire support that is at least partially disposed in the penetration unit, includes a coil lead wire insertion hole into which coil lead wires extending from the coils are provided, and is made of an insulating material. The coil lead wire support includes a base and a fitting unit extending downward from the base, at least one of a circumferential length and a radial length of the fitting unit being shorter than the base, and the coil lead wire insertion hole is in the base and the fitting unit, and the coil lead wire is inserted into the coil lead wire insertion hole.

Motor

A motor includes a rotor including a shaft, a stator, an upper bearing supporting an upper side of the shaft, a lower bearing supporting a lower side of the shaft, a bearing holder supporting the upper bearing, a housing accommodating the rotor, the stator, and the bearing holder and including an opening on an upper side, and a controller electrically connected to coil lead wires, and having an electronic component mounted thereon. An outer circumferential surface of the bearing holder is fixed while contacting an inner circumferential surface of the housing, and the bearing holder includes a notch cutout extending inward from the outer circumferential surface, and at least one of a the coil lead wires extends upward through the notch.

A circuit board is in the shape of a strip and includes: in one longitudinal end portion thereof, power connection portions connected to an external power supply; in another longitudinal end portion thereof, land portions to which portions of conducting wires drawn out downwardly of a base portion are connected; and pattern portions electrically connected to the power connection portions and the land portions. The land portions include a first land portion, and a second land portion arranged adjacent to the first land portion. The pattern portions include a first pattern portion electrically connected to the first land portion, and a second pattern portion arranged adjacent to the first pattern portion, and electrically connected to the second land portion. The first pattern portion and the second land portion are arranged to overlap with each other when viewed in a widthwise direction of the circuit board. Alternatively or additionally, the first and second land portions are arranged to overlap with each other when viewed in a longitudinal direction of the circuit board.

A fluid dynamic bearing apparatus includes a stationary body, a rotating body, and a lubricating oil arranged therebetween. One of the stationary and rotating bodies includes a shaft. Another one of the stationary and rotating bodies includes a sleeve. The sleeve includes a communicating hole arranged to pass therethrough in an axial direction or obliquely with respect to the axial direction. A groove array is defined in the stationary body or the rotating body to cause the lubricating oil to flow into the communicating hole. An opening area of an inlet of the communicating hole may be arranged to be greater than a cross-sectional area of a tubular portion of the communicating hole to make it easier for the lubricating oil to flow into the communicating hole. Further, the shape of the inlet may be modified to make a loss coefficient at the inlet lower than a loss coefficient at an outlet. This contributes to preventing a leakage of the lubricating oil.

Fluid dynamic bearing apparatus, spindle motor, and disk drive apparatus

A case of a disk drive apparatus includes a housing in which a disk is accommodated, and a top cover arranged to close an opening of the housing. The top cover includes a top cover body and a flow control member. The top cover body is a plate-shaped member arranged to extend perpendicularly to a central axis. The flow control member is fixed to a lower surface of the top cover body. The flow control member includes a lower surface arranged axially opposite to at least a portion of an upper surface of the disk.

Top cover and disk drive apparatus

A fluid bearing apparatus includes a stationary member and a rotating member. A bearing surface of the stationary member and a bearing surface of the rotating member are arranged opposite to each other with a minute gap intervening therebetween. A lubricating fluid is arranged in the minute gap. At least one of the bearing surfaces includes a dynamic pressure groove, and a plurality of striations defined in a bottom portion of the dynamic pressure groove. Each of the dynamic pressure groove and the striations is arranged to extend in a direction at an angle greater than 0&#xb0; to a circumferential direction. An angle defined between each striation and the circumferential direction is equal to or smaller than an angle defined between the dynamic pressure groove and the circumferential direction. Thus, an improvement in a force of dynamic pressure at the dynamic pressure groove is achieved.

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Kyoto, Japan

Mitsuo Kodama