Fluid bearings for electronic spindle motors
US5536088A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1995 |
| Grant date | Jul 16, 1996 |
| Priority date | — |
| Expiry date | Jun 7, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K5/124
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A construction for an electric spindle motor includes a stationary central shaft with a horizontal thrust bearing plate and a rotating hub assembly. A flanged thrust bearing ring having an upper capillary surface is affixed to the hub assembly. An annular end cap having a lower capillary surface is nested within the flanged bearing ring. The upper and lower capillary surfaces are radially outwardly diverging horizontal surfaces relative to each other which define a capillary cavity. Lubricating fluid partially fills the capillary cavity to form a horizontal capillary seal which prevents the fluid from escaping the motor. The capillary seal may be formed by tapering either the upper or lower capillary surfaces to provide an enlargement of the bearing cavity in an axial direction radially outwardly from the central shaft. Alternatively, the capillary seal may be formed by substantially coating the upper and lower capillary surfaces with a barrier coating to increase surface tension. Additional capillary seals may also be included in the invention. Vents, undercuts, and groove patterns may be included to further prevent fluid from escaping the motor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.