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:
Apr. 07, 1992
Filed:
Mar. 04, 1991
Yoshinobu Honkura, Aichi, JP;
Hideki Fujii, Aichi, JP;
Hideo Arakawa, Nagoya, JP;
Kazumasa Sumi, Nagoya, JP;
Aichi Steel Works Ltd., Aichi, JP;
Kebushiki Kaisha Toyota Chuo Kenkyusho, Aichi, JP;
Abstract
Permeameter suited for measuring permeability of a small, non-magnetic (i.e., the permeability value is close to 1) object. The probe of the permeameter is of the differential transformer type with an exciting coil and two detecting coils placed at both ends of the exciting coil. The difference in the outputs of the detecting coils is analyzed and the effect of the eddy current is effectively eliminated, whereby the signal representing the permeability of the object is extracted from the difference signal by the phase shift analysis. By reducing the distance between the two detecting coils, the influence of the disturbance of the eddy current at the boundary of the object sample is minimized and the permeameter can measure a small object sample without sacrificing accuracy and sensitivity.