Magnetic tachometer for disk drives
US4622516A · kind A · utility
8Cited by
5References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 16, 1983 |
| Grant date | Nov 11, 1986 |
| Priority date | — |
| Expiry date | Jun 16, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/5521
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A magnetic tachometer for generating a signal as a function of the velocity of a transducer positioning arm in a disk drive. The tachometer is formed by a pair of fixed parallel coils separated by a distance sufficient to allow a magnet, attached to a counterbalance portion of the rotary positioning arm, to move therebetween and thus to generate a voltage as a function of the velocity of the magnet. The coils are each wound over a thin armature member which is saturated by the magnet's magnetic field and they are differentially coupled to produce common mode rejection.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.