Perpendicular magnetic recording system with helical write coil and auxiliary coil for fast switching of write pole magnetization
US8116031B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 6, 2009 |
| Grant date | Feb 14, 2012 |
| Priority date | — |
| Expiry date | Jul 16, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/001
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A perpendicular magnetic recording system has a write head having a main helical coil (the write coil) and main pole (the write pole) that directs write flux in a direction perpendicular to the recording layer in the magnetic recording medium, and an auxiliary coil and auxiliary pole that injects magnetic flux into the write pole at an angle to the primary or perpendicular axis of the write pole. The auxiliary coil is preferably a helical coil wrapped around the auxiliary pole. The additional flux from the auxiliary pole, which is injected non-parallel to the primary magnetization of the write pole, exerts a relatively large torque on the magnetization of the write pole, thereby facilitating magnetization reversal of the write pole. Electrical circuitry is connected to the main coil and the auxiliary coil to generate the auxiliary flux simultaneous with the switching of the magnetization of the write pole.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.