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. 14, 2010
Filed:
Feb. 16, 2006
Yoshinori Inoue, Nagoya, JP;
Norikazu Ieda, Nagoya, JP;
Masahiro Tanaka, Nagoya, JP;
Reina Fukagai, Nagoya, JP;
Yoshinori Inoue, Nagoya, JP;
Norikazu Ieda, Nagoya, JP;
Masahiro Tanaka, Nagoya, JP;
Reina Fukagai, Nagoya, JP;
NGK Spark Plug Co., Ltd., Aichi, JP;
Abstract
To provide a malfunction diagnosing method and apparatus capable of reliably determining a malfunction even where the malfunction occurs in a common wire connecting a gas sensor and a control circuit for driving it. In a gas concentration measurement unithaving a sensor control circuitwhich is connected to a sensor elementincluding an oxygen pump celland an oxygen concentration detection celland controls and drives this sensor element, a variation state of a terminal voltage at one connecting point (specifically, a Vs+ terminal) other than connecting points between electrodes facing a measurement chamber of each cellandand a common wireis detected by a malfunction detection circuitand an arithmetic processor. Based on this variation state of the terminal voltage, diagnosis of malfunction in the common wireis executed. When the common wireis broken, the terminal voltage at the Vs+ terminal varies with oscillations. Therefore, the malfunction detection circuitand the arithmetic processordetect this voltage variation with oscillations to output a malfunction determination signal to a CPU.