Nidec Corporation

Seagate Technology Incorporated

Hiroki Yamada

Junya Mizukami

Takuro Iguchi

Tsuyoshi Morita

Tetsuya Maruyama

Troy Michael Herndon

Norbert Steven Parsoneault

Jeffry Arnold LeBlanc

Timothy Edward Langlais

Atsushi Watashita

Keisuke Kawata

A motor includes a shaft, a bearing that rotatably supports the shaft, and a hub fixed to the shaft. The shaft includes a first shaft portion extending in an axial direction, a second shaft portion projecting axially upward from an axially upper end surface of the first shaft portion and including a diameter smaller than that of the first shaft portion, and a screw hole recessed axially downward from the axially upper end surface. The hub includes a shaft fixing hole into and in which the second shaft portion is inserted and fixed. An outer surface of the second shaft portion includes a first region, and a second region axially above the first region, and including surface roughness smaller than that of the first region.

Motor

A motor of a disk drive includes a stationary portion, a bearing portion attached to the stationary portion, and a rotating portion supported by the stationary portion to be rotatable about a central axis through the bearing portion. The stationary portion includes a stator in which multiple coils annularly extend around the central axis, and a base portion located below the stator. The base portion is a portion of a housing that defines an internal space accommodating the rotating portion, the bearing portion, and the stator. The base portion includes a through hole that guides a lead drawn from the coil from the internal space of the housing to the outside. The through hole is filled with an adhesive, and includes an inclined hole that is inclined axially downward.

Motor and disk drive

Provided is a base unit for use in a disk drive apparatus and to be attached to a cover portion to define an enclosed space to be filled with a gas having a density lower than that of air. The base unit includes a base portion arranged to extend radially and support a motor capable of rotating about a central axis extending in a vertical direction; and a lateral wall portion arranged to extend axially upward from an edge portion of the base portion. The base portion includes a part accommodating portion defined by a through hole arranged to pass through the base portion in an axial direction, and arranged to accommodate at least a portion of a predetermined part; and a seal member arranged to close an end portion of the through hole on one axial side. The base portion and the lateral wall portion include a base made of a metal; a coating portion formed by electrocoating a surface of the base with at least a resin; and at least one exposed portion where the surface of the base is exposed. The at least one exposed portion is arranged in at least one of a predetermined first region and a second region. The first region lies on an axially upper end portion of the lateral wall portion, the axially upper end portion being opposite to the cover portion. The second region lies on an outer surface of the base portion, and is arranged to extend outward from an edge of the part accommodating portion so as to have a predetermined width.

Base unit and disk drive apparatus

In a fluid dynamic bearing apparatus, an oil buffer is defined between a thrust gap and a pumping gap. The oil buffer has an axial dimension greater than that of the thrust gap, and/or has a radial dimension greater than that of the pumping gap. An air bubble generated in the thrust gap due to cavitation, for example, when a fluid dynamic bearing apparatus experiences a vibration can be dissolved in lubricating oil provided within the oil buffer. This prevents leakage of the lubricating oil due to the air bubble residing in the fluid dynamic bearing apparatus.

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

A fluid dynamic bearing apparatus includes a first minute gap, a second minute gap, a third minute gap, a fourth minute gap, and a fifth minute gap. A flow of a lubricating oil from the fifth minute gap to the fourth minute gap is caused by a plurality of dynamic pressure generating grooves arranged within the fluid dynamic bearing apparatus. This flow causes air bubbles mixed in the lubricating oil within the fifth minute gap to flow toward the third minute gap and be discharged to an outside of the fluid dynamic bearing apparatus through the third minute gap. The fluid dynamic bearing apparatus further includes a plurality of dynamic pressure generating grooves and an annular groove.

Fluid dynamic bearing apparatus with specific minute gap structure with spindle motor and disk drive apparatus including same

A fluid dynamic bearing apparatus includes a first minute gap, a second minute gap, a third minute gap, a fourth minute gap, and a fifth minute gap. A flow of a lubricating oil from the fifth minute gap to the fourth minute gap is caused by a plurality of dynamic pressure generating grooves arranged within the fluid dynamic bearing apparatus. This flow causes air bubbles mixed in the lubricating oil within the fifth minute gap to flow toward the third minute gap and be discharged to an outside through the third minute gap. In addition, a flow of the lubricating oil into the third minute gap caused by a centrifugal force accompanying rotation is inhibited.

Growing community of inventors

Kyoto, Japan

Hiroki Yamada