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:
Oct. 05, 1982
Filed:
Aug. 25, 1980
Nobuo Kurihara, Hitachiota, JP;
Mitsuyo Nishikawa, Hitachi, JP;
Yoshitoshi Nagahashi, Hitachi, JP;
Masafumi Takechi, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a rotary machine mounted on a rotary shaft journaled in journal bearings, a source of unusual vibration of the rotary machine is identified on the basis of the results of the steps of (1) subjecting a shaft vibration signal to frequency analysis for analyzing its frequency distribution, and (2) analyzing the amplitude of the shaft vibration signal and the variation rate of a phase signal of a component related to the shaft rotation frequency among the frequency components of the shaft vibration signal. The present invention is usefully applicable to diagnosis of vibration of a rotary shaft of a large-size turbine or a generator in a power plant by continuously monitoring the shaft vibration for immediately automatically detecting unusual vibration of the rotary machine in the event of occurrence of such unusual vibration. The usefulness is more enhanced when the signal indicative of vibration of the rotary shaft is converted into a digital signal to be analyzed by a digital computer which identifies the source of unusual vibration.