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. 17, 1978
Filed:
May. 02, 1977
John F Wolfinger, Schenectady, NY (US);
General Electric Company, Schenectady, NY (US);
Abstract
An alarm system is disclosed for generating alarms when torsional oscillations of a rotating shaft exceed predetermined limits and fail to subside at a predetermined rate. The alarm system receives a torsional oscillation input signal developed by measuring the deviation of instantaneous shaft angle from a uniformly increasing value. The input signal is converted to a direct current torsional oscillation signal representative of the magnitude of oscillation. The torsional oscillation signal is compared against a first adjustable reference voltage representative of a first maximum magnitude of oscillation. A low level alarm signal is generated when the oscillation signal exceeds the first reference voltage for a predetermined length of time. The oscillation signal is also compared against a second reference voltage representative of a second maximum magnitude of oscillation. An output signal is generated when the oscillation signal exceeds the second reference voltage. The output signal is then employed to activate a rate of decay circuit which generates a signal representative of the rate of decay of the oscillation signal. This representative rate of decay signal is compared against a third reference voltage representative of a minimum acceptable rate of decay. If the representative rate of decay signal exceeds the third adjustable reference voltage, a high level alarm signal is generated to indicate that the second maximum magnitude of oscillation has been exceeded and that the minimum required rate of decay has not been attained.