Multiple-sense thermo-resistive sensor for contact detection of read-write heads
US8854764B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 2011 |
| Grant date | Oct 7, 2014 |
| Priority date | — |
| Expiry date | Mar 4, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/607
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Techniques of the present invention include detecting a touchdown between a read/write head of a disk drive and a surface of a magnetic disk using multiple touchdown sensors located at an air-bearing surface (ABS). The multiple sensors increase the likelihood that a touchdown event—i.e., a portion of the ABS of the head contacting the underlying magnetic disk surface—will be detected. During touchdown, the portion of the head contacting the magnetic disk generates frictional heat which changes a characteristic (e.g., the electrical resistance) of at least one of the sensors located at the ABS. When the sensors are connected to a detection circuit, the changing characteristic may be monitored to identify a touchdown event. The touchdown sensors may be, for example, electrically connected in either series or parallel to the detection circuit. Thus, as long as the electrical resistance of one of the sensors is changed, a touchdown event may be detected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.