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:
Jul. 24, 2001
Filed:
Mar. 01, 1997
Lloyd Douglas Clark, San Francisco, CA (US);
Other;
Abstract
An assembly of probes (,) measures both the electrical properties and the depth of a fluid (,). A first probe section (,) is electrically energized, while a second probe section (,) is de-energized. In a first measurement, the electrical properties of the fluid are measured. Low- and high-frequency, alternating potentials are used in measuring the conductivity and dielectric constant of the fluid. These potentials cause a current to flow in the fluid and also in a proximate conductor (,), which is connected to the input of an operational amplifier (,). The operational amplifier converts the current to a voltage whose amplitude and phase are measured using a precision rectifier (,), a voltmeter (,) and an oscilloscope (,) (or alternatively with an analog-to-digital converter (,), and a microprocessor (,)). A similar measurement is made with a second probe section (,) also energized. The electrical properties of the fluid (,) previously determined are then used in combination with a second current measurement and knowledge of the geometry of the second probe (,) to determine the depth of immersion of both probes in the fluid.