The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 25, 2010
Filed:
Jan. 19, 2007
Shinji Sasaki, Kanagawa, JP;
Makoto Torigoe, Yokohama, JP;
Takayoshi Ohtsu, Kanagawa, JP;
Kouji Kataoka, Kanagawa, JP;
Shinji Sasaki, Kanagawa, JP;
Makoto Torigoe, Yokohama, JP;
Takayoshi Ohtsu, Kanagawa, JP;
Kouji Kataoka, Kanagawa, JP;
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
A magnetic head suffers mechanical stresses by striking against a magnetic disc surface and dust, so that there are problems such as the reduction of reproduction output due to the mechanical stresses and the reversal of output polarity due to the mechanical stresses. Embodiments in accordance with the present invention relate to a method of testing reliability of reproduction elements of a magnetic head against outside stress. In a first step, a Giant Magnetoresistive (GMR) element on a row bar of the object of inspection, or a GMR element on a slider is measured for the output against external magnetic field. In the next step, prescribed shearing stress is applied with indenter to the edge where the GMR element-formed surface of the row bar or slider and the air-bearing surface are crossed. Then, output of the GMR element is measured again. Lastly, the outputs of the GMR element before and after application of stress are compared. When the amount of degradation is higher than the prescribed standard, the product is regarded as disqualified. Satisfaction of the prescribed standard is regarded as acceptance.