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. 22, 2015
Filed:
May. 21, 2012
Philippe Grass, Regensburg, DE;
Denny Schädlich, Neustadt, DE;
Philippe Grass, Regensburg, DE;
Denny Schädlich, Neustadt, DE;
Continental Automotive GmbH, Hannover, DE;
Abstract
A method for operating a selective catalytic reduction (SCR) system having a urea solution supply and an ultrasound based urea concentration sensor, the measurement signal of the urea concentration sensor being representative of a propagation time of an ultrasonic pulse along a predefined path length in a fluid of the urea solution supply includes: heating at least the fluid in a detection region of the urea concentration sensor from a predefined first temperature to a predefined second temperature; during the heating, detecting the measurement signal at at least a third and fourth temperature, and in each case determining a raw concentration characteristic value as a function of the respective measurement signal, which raw concentration characteristic value is representative of the propagation time of the ultrasonic pulse; and determining a concentration characteristic value, representative of a concentration of urea in the fluid, as a function of the raw concentration characteristic values.