Title:
MAGNETIC ENCODER
Document Type and Number:
Japanese Patent JPH01202618
Kind Code:
A
Abstract:
PURPOSE:To enable accurate detection of a position regardless of a spacing change, by a method wherein a fine magnetization is performed reversely to suppress a leak magnetic field at both ends of a magnetized zone to eliminate an abnormal output otherwise developed at an end of the magnetized zone. CONSTITUTION:As an MR element R2 moves through 101-103..., an output waveform voltage is detected. Here, as a magnetic field exists at the portion 101 across the width of a sensor pattern of the element R2 to generate an abnormal output. To eliminate the magnetic field across the width of the sensor pattern, magnetization is performed in a non-magnetized zone at a pitch of about 0.2-0.4 p when a magnetization pitch in a magnetized zone is set at (p). As a result, an abnormal output at a portion 51 can be eliminated by suppression. Thus, a fine magnetization applied to the non-magnetized zone at tracks of a magnetic disc can eliminated a magnetic field otherwise developed across the width of an MR sensor except for the magnetized zone, eventually getting rid of abnormal outputs completely.
Inventors:
ONO HIROYUKI
IKEDA MITSUAKI
KAKO HISAYUKI
HAYAKAWA HIROTOSHI
HARA KENJI
IKEDA MITSUAKI
KAKO HISAYUKI
HAYAKAWA HIROTOSHI
HARA KENJI
Application Number:
JP2668888A
Publication Date:
August 15, 1989
Filing Date:
February 09, 1988
Export Citation:
Assignee:
AGENCY IND SCIENCE TECHN
International Classes:
G01D5/245; (IPC1-7): G01D5/245
Domestic Patent References:
| JP61104304B |
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