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:
Jun. 30, 1998
Filed:
Jun. 26, 1997
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G01N / ;
U.S. Cl.
CPC ...
356432 ; 356433 ;
Abstract
In order to diagnose non-distructively the deterioration degree of such as insulation oil and insulation paper during operation of an oil filled electrical machine and apparatus without stopping the operation thereof, a deterioration degree disgnosis method for the oil filled electrical machine and apparatus makes use of optical fibers (6, 7) and oil immersed probe (5) and diagnoses the deterioration degree of an insulation paper non-distructively based on reflection absorbance difference between those for any two wavelengths of the insulation paper.