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:
Mar. 31, 1998
Filed:
Oct. 04, 1996
Applicant:
Inventors:
Shigeru Shouji, Hamamatsu, JP;
Atsushi Toyoda, Hamamatsu, JP;
Assignee:
Yamaha Corporation, , JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ; G11B / ;
U.S. Cl.
CPC ...
360126 ; 360119 ;
Abstract
A lower pole gradually increases its thickness in a section from the pole front end surface toward the depth direction. An upper pole gradually increases its thickness in a section from the pole front end surface toward the depth direction. The lower pole has a constriction at an area deeper than the gradually increasing section.