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:
Dec. 13, 1988
Filed:
May. 05, 1987
Applicant:
Inventors:
Dale R Pfost, San Carlos, CA (US);
R Fred Pfost, Los Altos, CA (US);
Eric W Lachenmeier, San Jose, CA (US);
Assignee:
Beckman Instruments, Inc., Fullerton, CA (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01F / ;
U.S. Cl.
CPC ...
7329 / ; 367908 ;
Abstract
A liquid boundary level detector employing an open-ended conduit which directs pressure waves toward a liquid boundary layer. The conduit is moved from a starting position toward the liquid boundary and, upon contact with the boundary, there is a change in acoustic impedance within the conduit. This change is monitored and a signal is generated indicative of such contact. Once the initial liquid boundary position is determined, that may become the reference position for subsequent liquid boundary measurements or motions.