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US 9,310,331 B2Granted
NOx detection apparatus and NOx sensor system
AssigneeNgk Spark Plug Co., Ltd.
InventorsHirotaka Onogi, Yuichi Ishida, Satoshi Teramoto
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AssigneeNgk Spark Plug Co., Ltd.
InventorsHirotaka Onogi, Yuichi Ishida, Satoshi Teramoto
Estimating the term…
An NOx detection apparatus does not always perform correction processing, but it determines whether to perform the correction processing on the basis of the result of a determination of whether a first Nox concentration is higher than a predetermined specific concentration. The first NOx concentration NOxpo calculated from a second pumping current Ip2 which changes with the actual NOx concentration. Therefore, the NOx detection apparatus can determine whether to correct the first NOx concentration NOxpo in accordance with the actual NOx concentration. Accordingly, the NOx detection apparatus can suppress a decrease in gas detection accuracy even in the case where the gas detection value based on the sensor output involves an error in a specific concentration range (concentration range of 90 ppm or higher).
An NOx detection apparatus connected to an NOx sensor and adapted to detect an NOx concentration within a to-be-measured gas, the NOx sensor including a first measurement chamber, a first pumping cell including paired first electrodes positioned internally and externally, respectively, of the first measurement chamber, the first pumping cell adjusting an oxygen concentration of the to-be-measured gas introduced into the first measurement chamber, an NOx measurement chamber in communication with the first measurement chamber, and a second pumping cell including paired second electrodes positioned internally and externally, respectively, of the NOx measurement chamber, a second pumping current flowing between the paired second electrodes and corresponding to the NOx concentration within the to-be-measured gas whose oxygen concentration has been adjusted in the first measurement chamber,
An NOx sensor system comprising:
Dependencies are inferred from the claim text.
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Cells and probes with solid electrolytes: for investigating or analysing gases
Using cells , i.e. more than one cell and probes with solid electrolytes: measuring voltages or currents with a combination of oxygen pumping…
Specially adapted to detect a particular component: nox
Investigating or analysing materials by determining their chemical or physical properties
About 7 years 10 months of term left · ends 26 Aug 2034 (estimated)
The present application claims priority from Japanese Patent Application No. 2012-251344, which was filed on Nov. 15, 2012, the disclosure of which is herein incorporated by reference in its entirety.
1. Field of the Invention
The present invention relates to an NOx detection apparatus connected to an NOx sensor which detects the concentration of NOx contained in a to-be-measured gas, and to an NOx sensor system.
Illustrative aspects of the invention will be described in detail with reference to the following figures wherein:
FIG. 1 is a block diagram showing the configuration of an NOx sensor control apparatus (NOx detection apparatus) according to a first embodiment of the present invention.
FIG. 2 is a table representing a map for determining an NOx pressure correction coefficient (k1).
Preferred embodiments of the present invention will next be described with reference to the drawings. However, the embodiments to be described below are mere examples of an application of the technical concept of the present invention. The contents of the embodiments should not be construed as limiting the invention.
FIG. 1 is a block diagram showing the configuration of an NOx sensor system 1 according to a first embodiment of the present invention. This embodiment is an example in which the NOx sensor system 1 corrects an oxygen concentration equivalent value and an NOx concentration equivalent value in accordance with pressure of exhaust gas.
The NOx sensor system 1 includes at least an NOx sensor control apparatus 10 (hereinafter also referred to as an “NOx detection apparatus 10”) and an NOx sensor 100.