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:
Sep. 29, 2015
Filed:
Oct. 02, 2007
Armin Wernet, Rheinfelden, DE;
Roland Dieterle, Lörrach, DE;
Kaj Uppenkamp, Wehr, DE;
Endress + Hauser GmbH + Co. KG, Maulburg, DE;
Abstract
An apparatus for determining and/or monitoring a process variable of a medium in a container. including: a probe unit, which has a sensor electrode and a guard electrode; and an electronics unit, which supplies the sensor electrode with an activating signal and which supplies the guard electrode with a guard signal; An amplifying unit; and a limiting element arranged in series between the guard electrode and the output of the amplifying unit. The amplifying unit supplies via the limiting element the guard electrode with the guard signal; and the amplifying unit supplies via the limiting element the sensor electrode with the activating signal. The evaluating unit is provided, which determines and/or monitors the process variable based on an electrical current signal measurable at the sensor electrode, and the activating signal and/or the guard signal.