公开(公告)号：US6092369A

公开(公告)日：2000-07-25

申请号：US195431

申请日：1998-11-18

申请人： Shigeo Hosogai ,  Hiroshi Kubota ,  Shigeo Hidai

发明人： Shigeo Hosogai ,  Hiroshi Kubota ,  Shigeo Hidai

IPC分类号： G01N27/409 ,  F01N3/20 ,  F01N11/00 ,  F02D19/02 ,  F02D41/14 ,  F02M21/02 ,  G01N27/26 ,  F01N3/00

CPC分类号： F01N11/002 ,  F01N11/007 ,  F01N2550/02 ,  Y02T10/47

摘要： A catalyst deterioration-determining system for an internal combustion engine has a catalyst arranged in the exhaust system, for purifying exhaust gases emitted from the engine, an oxygen concentration sensor arranged in the exhaust system at a location downstream of the catalyst, for detecting the concentration of oxygen present in the exhaust gases, and an ECU which controls the air-fuel ratio of an air-fuel mixture supplied to the engine in a feedback manner in response to the output from the oxygen concentration sensor. Determination of deterioration of the catalyst is carried out based on the output from the oxygen concentration sensor during execution of air-fuel ratio feedback control. An inversion period parameter representative of a repetition period of change in the output from the oxygen concentration sensor over a predetermined diagnosis period is measured, and a determination parameter is calculated by averaging values of the inversion period parameter measured over different diagnosis periods as the predetermined diagnosis period. The determination of deterioration of the catalyst is carried out based on the determination parameter.

摘要翻译： 一种用于内燃机的催化剂劣化判定系统，具有布置在排气系统中的用于净化从发动机排出的废气的催化剂，布置在该催化剂下游位置的排气系统中的氧浓度传感器，用于检测浓度 存在于排气中的氧气;以及ECU，响应于氧浓度传感器的输出，以反馈方式控制供给发动机的空气燃料混合物的空燃比。 基于在执行空燃比反馈控制期间来自氧浓度传感器的输出，进行催化剂劣化的测定。 测量代表氧浓度传感器在预定诊断期间的输出的重复变化周期的反转周期参数，并且通过将在不同诊断周期测量的反转周期参数的平均值作为预定诊断来计算确定参数 期。 基于确定参数进行催化剂劣化的测定。