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:
Nov. 24, 1998
Filed:
Mar. 31, 1997
Tetsuo Andoh, Tokyo, JP;
Yoshinori Matsunaga, Tokyo, JP;
Takashi Kawano, Tokyo, JP;
Masanori Hondo, Tokyo, JP;
Masami Wada, Tokyo, JP;
Kazuo Nagata, Tokyo, JP;
Yokogawa Electric Corporation, Tokyo, JP;
Abstract
A vortex flowmeter for calculating the flow rate of a measuring fluid flowing through a flow path using ultrasonic signals subjected to changes in the propagation time due to Karman vortices, comprising a reference signal generating device for outputting a plurality of reference signals of different phases; a signal analyzing device for outputting an input status signal by determining the relationship between the phases of the ultrasonic signals and each reference signal; a plurality of phase detectors for outputting phase signals by detecting the phase difference between the ultrasonic signals and the reference signals; and a channel selector for selecting the optimum phase signal using the input status signal and for outputting the optimum phase signal as a selection signal, wherein the flow rate signals are computed and outputted using the selected phase signal. The vortices are thus stably detected even when a phase change due to the vortices in the vortex flowmeter is large.