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, 2007
Filed:
Feb. 06, 2004
David Scott Nyce, Apex, NC (US);
David Scott Nyce, Apex, NC (US);
Other;
Abstract
A capacitive fluid level sensor is disclosed that operates without the use of a float, wherein coplanar sensing electrodes disposed onto a dielectric substrate and positioned proximate a dielectric wall of a vessel containing a fluid, form a fringing field capacitance that changes in accordance with changes in the level of the fluid. The electrodes are electrically insulated from the measured fluid. The electrodes are sized and spaced to maximize response of the capacitance to changes in the level of the fluid, while minimizing the effects of the dielectric wall. The sensor is fabricated such that it can be positioned against the outside of a dielectric wall of a vessel, or embedded within a dielectric material. A low permitivity spacer and shield assembly are taught which reduces sensitivity to electric fields external to the vessel. An interdigital comb configuration of the electrodes is also disclosed in which depressions or gaps are formed into the dielectric substrate in an area of spacing of the electrodes.