Denso Corporation

Tomohiro Ueno

Shigeto Yahata

Eiji Takemoto

Sumitaka Ikeda

Tomoaki Kamei

The exhaust gas purification controller is applied to a system with a catalyst and a supply valve for urea water. The exhaust gas purification controller performs an abnormality diagnosis of the supply valve, and includes a urea water filling portion, a valve opening command portion and an abnormality determiner. The urea water filling portion drives the pump at a start of operation of the exhaust gas purification system to start filling the supply passage with the urea water. The valve opening command portion outputs a valve opening command when a urea water pressure in the supply passage exceeds a predetermined valve opening pressure after filling the supply passage is started. The abnormality determiner determines presence or absence of a sticking abnormality of the supply valve based on the urea water pressure after the output of the valve opening command.

Exhaust gas purification control device

A urea water supply system includes: a first supply valve for supplying urea water; a second supply valve for supplying urea water; a supply passage for connecting a urea water tank and the first and the second supply valves; and an electronic control unit (ECU). The supply passage branches to have a first supply passage extending from a branch point to the first supply valve and a second supply passage extending from the branch point to the second supply valve, and a volume of the first supply passage is greater than a volume of the second supply passage. The ECU opens the first supply valve while keeping the second supply valve closed, for starting filling of the supply passage with urea water, and thereafter determines completion of filling of urea water into the first supply passage.

Urea water supply system

A detection apparatus includes a detection unit, a control unit, a first setting unit, and a second setting unit. The detection unit is disposed in an exhaust path through which an exhaust gas flows, and detects a correlation value correlated with an amount of particulate matter (PM) attaching to an attachment element. The control unit controls a temperature of the attachment element to follow a target temperature while a regeneration process is performed to heat the attachment element so as to burn PM. The first setting unit sets the target temperature to be lower, as the amount of PM becomes larger. The second setting unit sets a completion timing of the regeneration process so that a period of the regeneration process becomes longer, as the amount of PM becomes larger or a temperature of the attachment element becomes lower while the regeneration process is performed.

Detection apparatus

In an ordinary mode, when an abnormality diagnosis of a PM sensor attached to a downstream opening downstream of a filter is performed, the PM sensor is moved to a first upstream opening upstream of the filter, and an exhaust gas is discharged from an engine. An ECU stores a program for the abnormality diagnosis. In an abnormality diagnosis mode, the ECU diagnoses the PM sensor by comparing an output value of the PM sensor to a standard output after performing the program. The first upstream opening may be closed by a cover in the ordinary mode.

Diagnosis method for determining the condition of an exhaust sensor

Exhaust gas purifying system for internal combustion engine

A detection apparatus includes a particulate matter (PM) detection unit, a temperature detection unit, and a correction unit. The PM detection unit includes an insulator, a pair of electrodes, and a detector. The insulator is disposed in an exhaust path of an internal combustion engine through which an exhaust gas flows. The pair of electrodes are arranged in contact with at least a part of the insulator. The detector detects a PM detection value which is a value correlated to an amount of PM in the exhaust gas. The temperature detection unit detects at least one of an exhaust temperature of the exhaust gas passing through the PM detection unit and an insulator temperature of the insulator. The correction unit corrects the PM detection value detected by the PM detection unit based on at least one of the exhaust temperature and the insulator temperature.

Particulate matter sensor, system, and method of using a correction unit

A detection apparatus is used to detect a failure of a particulate filter. The detection apparatus includes a PM (particulate matter) sensor, a timing estimating unit, and a failure determining unit. The PM sensor is disposed at a downstream side of the particulate filter in an exhaust passage. The PM sensor includes a pair of electrodes and detects an amount of the PM based on current passing through the PM deposited between the electrodes. The estimating unit estimates a failure-state energization timing at which the PM sensor starts to be energized due to the PM deposited between the electrodes assuming that the particulate filter has failed. The determining unit determines that the particulate filter is in a failure state when an actual energization timing of the PM sensor based on an output of the PM sensor is earlier than the failure-state energization timing estimated.

Growing community of inventors

Nagoya, Japan

Tomohiro Ueno