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. 07, 1990
Filed:
Aug. 08, 1989
Garnet Lewis, Temple Terrace, FL (US);
John G Crump, Barrington Hills, IL (US);
Gregory P Crump, West Caldwell, NJ (US);
Alert Technologies, Inc., Barrington Hills, IL (US);
Abstract
Apparatus for detection leakage of hydrocarbon-containing liquid, such as gasoline, from a generally cylindrical tank. The apparatus includes an elongate displacer having a vertical axis and extending substantially the full height of the liquid in the tank. The displacer has an upper end and a lower end with the displacer lower end terminating closely adjacent but spaced from the bottom of the tank. The displacer is made of a material having a coefficient of linear expansion of less than 20.times.10.sup.-6 inches per inch per degree centigrade. Furthermore, the displacer is substantially symmetrical about about any plane through its vertical axis and it has an outer surface which is a surface of revolution. The displacer has a varying diameter along its length corresponding to the horizontal surface area of the tank at the same height inside of the tank. The apparatus further includes a sensor for providing an indication of the weight of the displacer disposed in the liquid. The apparatus also includes a cable extending inside a upwardly extending pipe joining the tank and connecting the upper end of the displacer to the sensor.