Disk drive spindle motor with hole volume and component density relationship
US8675304B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 19, 2012 |
| Grant date | Mar 18, 2014 |
| Priority date | — |
| Expiry date | May 2, 2032 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C2370/12
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A motor includes a stationary portion and a rotating portion. The rotating portion includes a sleeve portion including one communicating hole arranged to extend completely there through from an upper surface to a lower surface thereof, and a cover portion including a hole portion. The axial extension range of the hole portion is arranged to overlap with the axial extension range of the communicating hole in a radial direction. A center of the hole portion is arranged on a plane including a central axis and a center of the communicating hole. The communicating hole and the hole portion are arranged on opposite sides of the central axis. The following inequality is satisfied: V2<(σ1/σ2)·V1, where σ1 is the density of the sleeve portion, V1 is the volume of the communicating hole, σ2 is the density of the cover portion, and V2 is the volume of the hole portion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.