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:
Aug. 21, 1990
Filed:
May. 08, 1989
Robert W Lade, Milwaukee, WI (US);
Herman P Schutten, Bayside, WI (US);
Joseph C Zuercher, Whitefish Bay, WI (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
The depth of a cavity or chamber (10') is measured by using the chamber as the resonator of an electronic oscillator (24) whose oscillations are coupled to fluid in the cavity by transducers (12, 13). Both the variable-depth main chamber (10') and a reference chamber (117) of fixed depth are measured. Variations in the data obtained from the chambers are caused by factors affecting the velocity of propagation of sound in the fluid. An accurate measurement of the depth of the main chamber is obtained by compensating direct data (at 42) obtained from the main chamber (10'), using, data (at 43) obtained from the fixed-depth reference chamber (117). In one embodiment an inertance orifice (121) is utilized between the two chambers. The fluid inertance of the orifice, together with the compliance of the fluid in the main chamber (10'), form a resonant system whose anti-resonant frequency is a measure of the dimensions of the main chamber. (Inertance is the acoustical equivalent of inductance.)