Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Phase Sensing Magnetic Recording Head

IP.com Disclosure Number: IPCOM000082030D
Original Publication Date: 1974-Sep-01
Included in the Prior Art Database: 2005-Feb-28
Document File: 2 page(s) / 51K

Publishing Venue

IBM

Related People

Jansen, RE: AUTHOR

Abstract

Position information for a magnetic head 10 with respect to a magnetic track 12, is derived from sensing the phase angle between the voltages VL and VR in the left and right sides 10a and 10b of head 10 in lieu of comparing amplitudes of the voltages.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 66% of the total text.

Page 1 of 2

Phase Sensing Magnetic Recording Head

Position information for a magnetic head 10 with respect to a magnetic track 12, is derived from sensing the phase angle between the voltages VL and VR in the left and right sides 10a and 10b of head 10 in lieu of comparing amplitudes of the voltages.

Head 10 comprises cores 14 and 16 having gaps 14a and 16a therein and a pair of side bars 18 and 20, respectively, completing the magnetic circuits with the cores 14 and 16. Coils 22 and 24 are wound on the side bars 18 and 20, and a spacer 26 of nonmagnetic material separates cores 14 and 16. Head 10 is located over track 12 written on the surface of magnetic disk 28, and track 12 moves in direction 30 beneath head 10 with rotation of disk 28.

Gaps 14a and 16a are disposed at an angle theta with respect to a normal, 32a, to the center line 32b of head 10. Track 12 is formed by magnetic transitions 12a and 12b which extend in the same directions as the gaps 14a and 16a; and transitions 12a and 12b are coextensive with these gaps, looking down on the top of head 10 and disk 28 as in Fig. 1 if the center line 32b of head 10 lies directly over the center line 34 of track 12.

The left and right transitions 12a and 12b of track 12 are written in phase radially on disk 28 (corresponding parts of a pair of transitions being on a disk radius 28a, for example), and information regarding the position of head 10 with respect to track 12 is derived from sensing the phase between the voltage...