Abgasreinigungsvorrichtung für einen Verbrennungsmotor

Details

Veröffentlichungs-Nr.

EP3075977

Aktenzeichen

EP16162404

Anmeldetag

24. März 2016

Veröffentlichung

17. Januar 2018

Erteilung

17. Januar 2018

Rechtsraum

EP

IPC

F01N3/20

Abstract

An exhaust purifying apparatus includes an adding valve, a urea water supply passage connected to the adding valve, a dispersion plate, a catalyst, and a controller. Urea water injected by the adding valve impinges on the dispersion plate. The catalyst removes NOx in exhaust gas by using ammonia generated from the urea water injected by the adding valve. The controller is configured to set an injection timing of the urea water such that the urea water is repeatedly injected from the adding valve at a predetermined injection cycle, thereby causing the adding valve to execute urea water injection. The controller includes a temperature calculating section, which is configured to calculate a temperature of the dispersion plate, a memory section, which is configured to store an injection pressure of the urea water at the urea water injection, a first injection pressure obtaining section, which is configured to obtain, as a first injection pressure, an injection pressure at a previous urea water injection stored in the memory section, a second injection pressure calculating section, and a third injection pressure calculating section. The second injection pressure calculating section is configured to calculate a second injection pressure. The second injection pressure is an injection pressure of urea water obtained in a case in which the urea water is injected when time corresponding to the injection cycle has elapsed from the previous urea water injection. The third injection pressure calculating section is configured to calculate a third injection pressure. The third injection pressure is an injection pressure of urea water obtained in a case in which the urea water is injected at a second timing, which is different from a first timing, which is an injection timing obtained from the injection cycle. The controller is configured to execute a pressure difference increasing process when the temperature of the dispersion plate calculated by the temperature calculating section is lower than a predetermined temperature threshold value, a first pressure difference, which is an absolute value of a difference between the first injection pressure and the second injection pressure, is less than a pressure difference threshold value, and injection of the urea water at the second timing will cause a second pressure difference, which is an absolute value of a difference between the third injection pressure and the first injection pressure, to be greater than the first pressure difference. In the pressure difference increasing process, the controller sets, as the urea water injection timing, the second timing, which is a timing at which the second pressure difference exceeds the first pressure difference.

Anmelder

Firma

Toyota Jidosha Kabushiki Kaisha

Land

🇯🇵 Japan

Fachgebiete