Denso Corporation

Shigeto Yahata

Tsukasa Kuboshima

Makoto Saito

Masumi Kinugawa

Kazuharu Tochikawa

Shinichiro Okugawa

Tomohiro Ueno

Kiyonori Sekiguchi

Kanehito Nakamura

Yuuki Tarusawa

Mao Hosoda

Satoru Nosaka

Yasuhiro Kariya

Keiji Noda

Yusuke Majima

Tsutomu Soga

Shinichirou Okugawa

Youhei Morimoto

Kazuo Kojima

Kojiro Tokuda

Atsushi Takano

Makoto Saitoh

A reducing agent supplying device includes a reforming device, an obtaining section and a controller. The reforming device mixes fuel, which is a hydrocarbon compound, with air, and reforms the fuel by partially oxidizing the fuel with oxygen in the air. A reformed fuel is supplied into the exhaust passage as the reducing agent. The obtaining section obtains a physical quantity as a property index. The physical quantity has a correlation with property of the fuel that is supplied to the reforming device. The controller controls the reforming device according to the property index obtained by the obtaining section.

Reducing agent supplying device

A reducing agent supplying device is for a fuel combustion system that includes a NOx purifying device with a reducing catalyst arranged in an exhaust passage to purify NOx contained in exhaust gas of an internal combustion engine. The reducing agent supplying device supplies a reducing agent into the exhaust passage at a position upstream of the reducing catalyst. The reducing agent supplying device includes a reforming portion and a reformation suppressing portion. The reforming portion reforms the reducing agent by partially oxidizing the reducing agent. When a temperature of the reducing agent is higher than a first specified temperature that is equal to or higher than an activation temperature of the reducing catalyst, the reformation suppressing portion (i) suppresses the degree of reformation of the reducing agent in comparison with when a temperature of the reducing agent is lower than the first specified temperature, or (ii) stops the reformation of the reducing agent.

A reducing agent supplying device includes a reaction container. The reaction container has a reaction chamber therein in which fuel of a hydrocarbon compound is mixed with air and is oxidized with oxygen in air. An equivalent ratio of fuel to air inside the reaction chamber is adjusted to be within a specified equivalent ratio range. A temperature inside the reaction chamber is adjusted to be within a specified temperature range. The specified equivalent ratio range and the specified temperature range are set such that a cool flame reaction, through which fuel inside the reaction chamber is partially oxidized with oxygen in air, is generated. The fuel partially oxidized through the cool flame reaction is used as the reducing agent.

A reducing agent supplying device includes a reaction container, an ozone generator, an air pump, an ozone-containing air pipe, a compressed air pipe, a switching device, and a switching controller. The reaction container defines a reaction chamber therein in which a reducing agent is reformed. The ozone generator generates ozone from oxygen in air. The air pump supplies air into the ozone generator. An ozone-containing air flows through the ozone-containing air pipe toward the reaction chamber. A portion of a compressed air flows through the compressed air pipe toward the reaction chamber. The switching device switches between an air pump mode, in which the ozone-containing air is supplied into the reaction chamber, and a supercharging mode, in which the compressed air is supplied into the reaction chamber. The switching controller controls the switching device based on a catalyst temperature, which is a temperature of the reducing catalyst, and an exhaust pressure, which is a pressure in the exhaust passage.

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.

Failure detection apparatus for particulate filter

A first intake air control mode of setting an intake throttle valve to (or close to) a fully-opened state and setting an EGR valve to (or close to) a fully-closed state is performed when DPF temperature and a particulate matter deposition quantity are greater than corresponding predetermined values respectively, a no-injection operation state exists, and engine rotation speed is higher than a corresponding predetermined value. A second intake air control mode of setting the intake throttle valve to (or close to) a fully-closed state and setting the EGR valve to (or close to) a fully-opened state is performed when the DPF temperature and the particulate matter deposition quantity are greater than the corresponding predetermined values respectively, the no-injection operation state exists, and the engine rotation speed is lower than the corresponding predetermined value.

Exhaust gas purification device of internal combustion engine

There is provided with an ECU for estimating an unburned fuel amount (HC) emitted from an engine after fuel combustion or a temperature of a DPF based upon a required engine operating condition as a control target value. An exhaust gas temperature sensor for detecting a temperature of an exhaust gas emitted directly from the engine is provided. A program for compensating for an estimation error in regard to an estimation value of the unburned fuel amount estimated from the required engine operating condition, that is, an operating condition difference amount between the required engine operating condition and an actual engine operating condition, based upon an engine exhaust gas temperature detected from the exhaust gas temperature sensor is provided.

Unburned fuel amount-estimating device in engine and temperature-estimating device of exhaust emission purifier

An exhaust gas purifying apparatus for an internal combustion engine includes a collector, a differential pressure sensing device, a differential pressure based estimating device, a partition wall exposure sensing device, and a second regenerating device. The collector captures exhaust particles in exhaust gas. The differential pressure sensing device senses a differential pressure across the collector. The differential pressure based estimating device estimates an accumulation amount of the exhaust particles based on the differential pressure. The partition wall exposure sensing device senses a partition wall exposure state. The second regenerating device forcibly completely combusts the exhaust particles captured in the collector when the partition wall exposure sensing device senses the partition wall exposure state.

Exhaust gas purifying apparatus

A control device has a throttle valve and fuel injection valves supplying air and fuel to an internal combustion engine, a meter detecting an actual quantity of the air supplied to the engine, a sensor detecting an actual oxygen concentration of an exhaust gas outputted from an exhaust system of the engine, and an ECU controlling the valves. To regenerate an exhaust emission purifier disposed in the exhaust system at a target temperature appropriate to the regeneration of the purifier, the ECU determines a target oxygen concentration corresponding to a target air-fuel ratio and a basic air quantity according to a torque required of the engine and controls the valves according to the actual air quantity and the actual oxygen concentration to supply a basic quantity of fuel and the basic quantity of air to the engine at the target air-fuel ratio.

Control device for internal combustion engine

A method is disclosed for estimating an amount of deposited particulates (PM) in a collector of an internal combustion engine. The method includes estimating the amount of inflow of PM into the collector and estimating a basic amount of decreased PM that flows into the collector and is burned and decreased. The method also includes estimating the amount of ash deposited on the collector. The method further includes correcting the basic amount of decreased PM based on the estimated amount of ash. Moreover, the method includes estimating an amount of deposited PM by a history expression based on the estimated amount of inflow of PM and the corrected amount of decreased PM. A related device is also disclosed.

Exhaust emission control device for internal combustion engine

A diagnostic apparatus monitors a pressure difference detection apparatus that detects the pressure difference across an engine exhaust gas cleansing device in an exhaust gas system, with the diagnostic apparatus recognizing a condition of impeded transfer of gas between the pressure difference detection apparatus and the exhaust gas system, based upon a manner of convergence of successive detected pressure difference values that are produced by the pressure difference detection apparatus following a change in the exhaust gas flow rate.

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Obu, Japan

Shigeto Yahata