| 摘要 |
<P>PROBLEM TO BE SOLVED: To diagnose abnormality of a particulate filter 14 by using exhaust flow rate sensors 41, 42 having resistance against stain caused by exhaust. <P>SOLUTION: The exhaust flow rate sensors 41, 42 are arranged on the upstream side and downstream side of the particulate filter 14 installed in an exhaust system of an internal combustion engine and abnormality such as damage and erosion of the particulate filter 14 is determined from a compared result of exhaust flow rates detected by the sensors 41, 42. Each of the exhaust flow rate sensors 41, 42 is composed of a beam-like sensing member 52 crossing an exhaust passage 13 and a semiconductor type strain sensor 53 for detecting strain of the sensing member 52. The sensing member 52 is composed of a thin flat-band-like plate spring or the like and finely deformed so as to be curved like a bow by an exhaust flow, so that an output corresponding to an exhaust flow rate is obtained by the strain sensor 53. <P>COPYRIGHT: (C)2013,JPO&INPIT |
