Spindle motor and pivot assembly
US6559573B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 16, 2001 |
| Grant date | May 6, 2003 |
| Priority date | — |
| Expiry date | Mar 16, 2021 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C2370/12
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A shaft 2 of a spindle motor is composed of a steel material including 0.20 wt % of C, 0.35 wt % of Si, 8.00 wt % of Mn, higher than 0 and equal to or less than 0.05 wt % of P, 0.15 wt % of S, higher than 0 and equal to or less than 2.00 wt % of Ni and 14.00 wt % of Cr and the remainder substantially being Fe. The steel material has corrosion resistance with no plating requirement and wear resistance with no need for a heat treatment and/or a soft nitriding. Further, when considering a conventionally employed stainless steel, Pb has been frequently added thereto in order to improve machinability. On the contrary, the steel material according to the embodiments of the present invention is Pb-free material.Since the shaft of the spindle motor is manufactured by a material high in its wear resistance, corrosion resistance and workability and in which the generation of the out gas of sulfur and sulfur compounds is suppressed low, the qualities of electronic devices and communication devices, etc. for a personal computer can be improved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.