Active magnetic bearing system for improved servo control
US6469863B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 19, 2000 |
| Grant date | Oct 22, 2002 |
| Priority date | — |
| Expiry date | Apr 19, 2020 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C2370/12
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Apparatus and method for improved servo control in a disc drive. The disc drive includes a rotatable disc, a moveable actuator which supports a head adjacent the disc, and a stationary active magnetic bearing assembly which uses bearing coils to levitate the actuator. An active magnetic bearing control circuit applies currents to the bearing coils, and a servo control circuit applies current to an actuator motor to position the head with respect to the disc. The active magnetic bearing control circuit outputs a disturbance signal when a disturbance affects the relative positioning of the actuator and the bearing assembly, and this disturbance signal is fed forward into the servo control circuit. Conversely, the servo control circuit provides a seek expectancy signal to the bearing control circuit to enable the bearing control circuit to compensate for torque forces applied by the actuator motor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.