CATALYST DETERIORATION DIAGNOSIS METHOD AND CATALYST DETERIORATION DIAGNOSIS SYSTEM

• Main Authors: OKAMOTO TAKU, NAKASONE OSAMU
• Format: Patent
• Language: English; Japanese
• Published: 19.03.2020
• Subjects: BLASTING; COMBUSTION ENGINES; CONTROLLING COMBUSTION ENGINES; ENGINE PLANTS IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNALCOMBUSTION ENGINES; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES ORENGINES IN GENERAL; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; LIGHTING; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; STEAM ENGINES; WEAPONS

To provide a catalyst deterioration diagnosis method capable of highly accurately performing diagnosis in the viewpoint of NHgeneration.SOLUTION: A catalyst deterioration diagnosis method is provided for a system including: a stepped transmission 400 or a stepless transmission connected to an internal combustion engine 500; a catalyst 601 into which an exhaust gas from the internal combustion engine 500 is introduced; and a gas sensor 702 outputting a detection value corresponding to a component of the exhaust gas passing the catalyst 601, and having a sensitivity to ammonium. The catalyst deterioration diagnosis method includes the steps of: acquiring a temporary increase amount of a detection value of the gas sensor 702 by starting to monitor a temporary increase in the detection value of the gas sensor 702 when performing shift-up by the stepped transmission 400 or dummy shift-up by the stepless transmission; and determining whether the temporary increase amount is greater than a threshold amount.SELECTED DRAWING: Figure 1 【課題】ＮＨ３発生の観点で、高精度で行うことができる触媒劣化診断方法を提供する。【解決手段】触媒劣化診断方法は、内燃機関５００に接続された有段変速機４００または無段変速機と、内燃機関５００からの排ガスが導入される触媒６０１と、触媒６０１を通過した排ガスの成分に対応する検出値を出力するものであってアンモニアに対する感度を有するガスセンサ７０２と、を含むシステムのためのものである。触媒劣化診断方法は、以下の工程を有している。有段変速機４００によるシフトアップまたは無段変速機による疑似シフトアップが行われるときにガスセンサ７０２の検出値の一時的増大をモニタし始めることによって、ガスセンサ７０２の検出値の一時的増大量が取得される。一時的増大量がしきい量よりも大きいか否かが判定される。【選択図】図１