Nidec Corporation

Harushige Osawa

Shigeo Hayashi

Atsushi Inoue

Hidehiko Hidaka

Tatsuya Tatara

Hiroyuki Ichizaki

Eiji Miyamoto

Masanobu Chuta

Kazuya Ichimura

Akihiro Nakagawa

Tomohiro Hasegawa

Hongbing Du

Shinya Tokunaga

Ming Feng

Itsuo Murata

A motor includes a bearing mechanism, a stationary unit including a stator arranged radially outwards of the bearing mechanism, and a rotary unit supported by the bearing mechanism at the upper side of the stationary unit for rotation about a center axis with respect to the stationary unit. The rotary unit includes a substantially cylindrical closed-top rotor yoke having a cover portion arranged to cover the stator. The bearing mechanism includes a substantially cylindrical closed-bottom bush formed by a press work, a sleeve fixed inside the bush and provided with an upper portion protruding beyond the bush and a shaft inserted into the sleeve. An upper end of the bush is lower than or flush with an upper end of the stator in a direction parallel to the center axis.

Motor and storage disk drive apparatus

A motor includes a stationary unit, a bearing mechanism, a rotary unit, and a chucking device. The rotary unit includes a rotor yoke provided with a cover portion extending around the chucking device and designed to allow the storage disk to be directly or indirectly mounted thereto and a removal-preventing member fixed to the cover portion to prevent removal of the rotary unit from the stationary unit. The removal-preventing member made of metal. The removal-preventing member includes a removal-preventing portion, an upper fixing portion having a plurality of upper protrusions inserted into the through-holes of the cover portion and bent toward the upper surface of the cover portion, and a lower fixing portion making direct or indirect contact with the lower surface of the cover portion and cooperating with the upper fixing portion to fix the position of the removal-preventing portion in a direction parallel to the center axis.

Motor, storage disk drive apparatus and motor manufacturing method

In a radial minute gap between a substantially columnar shaft and an inner peripheral face of a substantially cylindrical sleeve, oil is retained and a radial dynamic pressure bearing is formed. A plurality of recessed portions are arranged in a circumferential direction on at least one of an outer peripheral face of the shaft and the inner peripheral face of the sleeve and a first hill portion is provided to an axial end portion of each the recessed portion. Thus, it is possible to achieve a dynamic pressure bearing with which sufficient radial shaft support can be obtained in spite of a short axial length.

Fluid dynamic pressure bearing and recording disk drive device comprising the same

A head assembly supports an arm for angular displacement about an axis in a disk drive. The bearing assembly includes a fixed shaft , a plurality of bearings and , a sleeve and dampers . The bearings and are disposed about the shaft . The sleeve is coupled to the bearings and for angular displacement about the shaft , and one or more darpers are coupled to the sleeve. Each damper includes a plurality of holding portions and one or more damping masses the holding portions are arranged circumferentially about the axis of the shaft as an axis of rotation of the arm, and distance between each adjacent two damping portions is approximately equal to each other, each holding portion has an inner space. The damping masses are movably accommodated in the inner space of the respective holding portions. The energy of the vibration of the head and the arm is absorbed in a short time by movements of the damping masses and by friction between the damping masses and inner surface of the holding portion, and/or by collisions of the damping masses.

Bearing device with damping mechanism

A method for visualizing and indicating characteristics of vibration measurement data for a rotating or vibrating object. Specific components are removed from the measurement data or are minimized therein. After removing or minimizing the specific component, the measurement data is indicated in a Campbell diagram.

Method for indicating characteristics of rotating apparatus or vibrating apparatus

The present invention discloses a disk drive motor comprising a rotor having an annular space formed therein coaxially with the axis of rotation, and balancing member accommodated in the annular space and capable of changing its mass distribution circumferentially along the circle of the annular space. In case of any imbalanced rotation occurring during the rotation, the balancing member temporarily gather to a portion of the annular space where the mass imbalance is taking place. However, when the motor speed exceeds the value at which resonance takes place due to coincidence between the frequency of the vibration of the balancing member and the natural frequency of the motor, the balancing members move to a position symmetrical with the point of mass imbalance to eliminate the mass imbalance, thereby suppressing the run-out.

Disk drive motor

The present invention discloses a disk drive motor comprising a rotary member having an annular space formed therein coaxially with the axis of rotation, and ring-shaped balancing members accommodated in the annular space and capable of changing its mass distribution circumferentially along the circle of the annular space. In case of any imbalanced rotation occurring during the rotation, the balancing members temporarily gather at a portion of the annular space where the mass imbalance is taking place. When the motor speed exceeds the value at which resonance takes place due to coincidence between the frequency of the vibration of each of the balancing member and the natural frequency of the motor, the balancing members move to a position symmetrical with the point of mass imbalance to eliminate the mass imbalance, thereby reducing motor run-out.

Growing community of inventors

Kyoto, Japan

Harushige Osawa