公开(公告)号：US20180073456A1

公开(公告)日：2018-03-15

申请号：US15670037

申请日：2017-08-07

Applicant: DENSO CORPORATION

Inventor： Tomohiro KOHARA ,  Yoshiyuki KAWASE ,  Kazunori KUROKAWA

IPC: F02D41/14 ,  G01N27/12

CPC classification number: F02D41/1456 ,  F02D41/1495 ,  F02D2041/281 ,  G01N27/122

Abstract: An air-fuel ratio sensing device includes a resistor, an A/D converter, a parallel circuit unit, a second switch, a controlling unit, an air-fuel ratio sensing unit, and a deterioration sensing unit. The controlling unit controls to turn off the first switch and controls to turn on the second switch in a first interval, and the controlling unit controls to turn on the first switch and controls to turn off the second switch in a second interval. The air-fuel ratio sensing unit senses an air-fuel ratio based on a converting result of the A/D converter in the first interval. The deterioration sensing unit compares a reference value with a value obtained based on the converting result and senses a deterioration generated in the current sensing circuit unit in the second interval.