Supplying power from a spindle motor in a disc drive system
US6639749B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 28, 1999 |
| Grant date | Oct 28, 2003 |
| Priority date | — |
| Expiry date | Oct 28, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B21/22
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system and method for unloading a transducer assembly to a ramp positioned outside an outer diameter of a disc in a disc drive system directs current generated from the back EMF (electromotive force) of a spindle motor to supplement current provided by a power supply to a positioning coil. The combined current yields increased torque to park the transducer assembly without requiring unnecessary power consumption during normal disc drive operation. The current generated from the back EMF of the spindle motor is enhanced by accelerating the rotation of the spindle motor to exceed the normal operational rotational velocity of the disc drive system. A position detector provides a trigger signal to control the timing of the switch that combines the current from the back EMF and the current from the power supply to the positioning coil. A modified voice coil motor configuration optimizes the magnetic flux density along the length of the voice coil motor magnets so as minimize unnecessary power consumption while optimizing the magnetic flux density in the region corresponding to the disc surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.