Toyota Jidosha Kabushiki Kaisha

The Doshisha

So-Ken Corporation

Kazuhiro Umemoto

Kohei Yoshida

Mikio Inoue

Yuki Bisaiji

Hiromasa Nishioka

Takamitsu Asanuma

Daichi Imai

Toshihiro Mori

Junichi Matsuo

Yoshihisa Tsukamoto

Masaaki Sato

Akira Mikami

Katsuhiro Ito

Ryohei Ono

Hiroshi Kobayashi

Masao Watanabe

Shigeki Nakayama

Yuka Nakata

Koutarou Hayashi

Hiroshi Otsuki

Takao Fukuma

Katsuhiko Oshikawa

Masahide Iida

Hiroyoshi Ueda

Eriko Matsumura

Jiro Senda

Tetsuro Serai

Kouhei Yoshida

Kenichi Tomomatsu

Takayoshi Kojima

Naoki Toda

The exhaust purification system of an internal combustion engine comprises a catalystarranged in an exhaust passage and able to store oxygen, and an air-fuel ratio control device configured to control an air-fuel ratio of inflowing exhaust gas flowing into the catalyst. The catalyst has a precious metal and the precious metal has a property of a vapor pressure at a predetermined temperature becoming lower when oxidized. If a temperature of the catalyst is equal to or greater than a threshold temperature or if predicting a rise in temperature of the catalyst, the air-fuel ratio control device is configured to make the air-fuel ratio of the inflowing exhaust gas leaner than a stoichiometric air-fuel ratio so that an oxygen storage amount of the catalyst becomes equal to or greater than an upper side reference amount.

Exhaust purification system of internal combustion engine

An exhaust purification system of an internal combustion engine is provided with: an exhaust purification catalyst supporting a precious metal and able to store oxygen; and a control device controlling an amount of fuel fed to a combustion chamber. When a predetermined condition for performing a fuel cut operation stands, the control device is configured to perform fuel feed control in which fuel is temporarily fed to the combustion chamber so that the air-fuel ratio of the exhaust gas flowing into the exhaust purification catalyst is a rich air-fuel ratio richer than the stoichiometric air-fuel ratio, then start fuel cut control stopping the feed of fuel to the combustion chamber in the state the internal combustion engine is operating.

An exhaust emission control device for an internal combustion engine according to the present disclosure includes an exhaust emission control catalyst provided in an exhaust passage in an internal combustion engine and divided into a preceding catalyst and a succeeding catalyst, and a heating device provided in the exhaust passage between the preceding catalyst and the succeeding catalyst. The exhaust emission control catalyst is divided into the preceding catalyst and the succeeding catalyst so that a ratio of a capacity of the preceding catalyst to a total displacement of the internal combustion engine is from 0.3 to 1.5.

Exhaust emission control device for internal combustion engine

An exhaust gas purification apparatus for an internal combustion engine includes the adsorbent, the catalyst and the heat generating element, wherein in cases where the residual capacity of the battery is smaller than a first predetermined value required for raising the temperature of the catalyst to an activation temperature thereof, and in cases where the residual capacity of the battery is larger than a second predetermined value which is smaller than the first predetermined value and which is required for raising the temperature of the adsorbent to a predetermined temperature at which the adsorbent exhibits adsorption performance required at the time of starting of the internal combustion engine, an amount of electric power to be supplied to the heat generating element from the battery is adjusted such that the temperature of the adsorbent becomes the predetermined temperature.

Exhaust gas purification apparatus for internal combustion engine

A controller estimates a first estimated adsorption amount which is an amount of adsorption of ammonia in the SCR catalyst at the time when the SCR catalyst is assumed to be in a predetermined abnormal state, estimates a second estimated adsorption amount at the time when the SCR catalyst is assumed to be in a predetermined normal state, calculates a first slip development temperature based on the first estimated adsorption amount, and calculates a second slip development temperature based on the second estimated adsorption amount. The controller, when carrying out an abnormality diagnosis based on a concentration of ammonia in an exhaust gas at the downstream side of the SCR catalyst, carries out diagnostic temperature control so as to control the temperature of the SCR catalyst to a temperature which is equal to or more than the first slip development temperature and is less than the second slip development temperature.

Abnormality diagnosis system for an exhaust gas purification apparatus

An exhaust gas control apparatus includes a fuel injection device, a NOx occlusion reduction catalyst, a fuel addition valve, an inflow gas adjustment device, and an electronic control unit. The electronic control unit executes a low flow rate reduction treatment for removing NOoccluded in the NOx occlusion reduction catalyst after fuel supply from the fuel injection device is stopped. The electronic control unit controls the inflow gas adjustment device such that a ratio of oxygen to the fuel added to the NOx occlusion reduction catalyst at a time when a temperature of the NOx occlusion reduction catalyst is below an activation temperature becomes higher than a ratio of oxygen to the fuel added to the NOx occlusion reduction catalyst at a time when the temperature of the NOx occlusion reduction catalyst is equal to or higher than the activation temperature during the low flow rate reduction treatment.

Exhaust gas control apparatus for internal combustion engine

The exhaust gas purification apparatus is applied to an internal combustion engine. The exhaust gas purification apparatus includes a SCR catalyst, a reducing agent addition valve, an oxidation catalyst, a fuel addition valve, and a controller. The controller is configured to add fuel into the exhaust gas through the fuel addition valve, in a case where the reducing agent is added to the exhaust gas through the reducing agent addition valve in a state where the temperature of the SCR catalyst is higher than a predetermined threshold value. The controller is further configured to control the fuel addition valve so that the amount of fuel added through the fuel addition valve is smaller in a case where the degree of deterioration of the SCR catalyst is smaller than in a case where the degree of deterioration is larger.

An exhaust gas control apparatus for an internal combustion engine is provided. The exhaust gas control apparatus is equipped with a NOx reduction catalyst, a reducing agent tank, a reducing agent supply device, a booster, a heater, and an electronic control unit. The electronic control unit is configured to perform control of raising a temperature of a reducing agent to a first target temperature such that the reducing agent supplied by the reducing agent supply device is brought into a gas-liquid mixed state in an exhaust passage, when energy of exhaust gas is lower than a first threshold.

Exhaust gas control apparatus for internal combustion engine and control method for exhaust gas control apparatus

The fuel addition system comprises: a fuel addition valve, a fuel tank, a first pressure storage chamber storing fuel to be supplied to a fuel injector, a supply pump increasing a pressure of fuel inside the fuel tank and supplying the fuel to the first pressure storage chamber, a pressure reduction valve discharging fuel stored in the first pressure storage chamber, a pressure reduction fuel passage supplying fuel discharged from the first pressure storage chamber to the fuel addition valve, and a control device controlling the fuel addition valve and the pressure reduction valve. The control device detects or estimates a temperature of fuel supplied to the fuel addition valve and, when injecting fuel from the fuel addition valve, controls an amount of fuel discharged from the first pressure storage chamber through the pressure reduction valve so that the temperature of the fuel becomes a reference temperature or more.

Fuel addition system

A control apparatus for an internal combustion engine having an exhaust gas purification device which is arranged in an exhaust passage and includes a NOx storage reduction (NSR) catalyst. The control apparatus, when the air fuel ratio of the air-fuel mixture is shifted from a lean air fuel ratio to the stoichiometric air fuel ratio, determines a predetermined NOamount so as to be larger when the temperature detected by the first detection unit is high in comparison with when the detected temperature is low, and when the storage amount of NOin the NSR catalyst is larger than the predetermined NOamount, performs the rich spike processing and then controls the air fuel ratio to the stoichiometric air fuel ratio, whereas when otherwise, controls the air fuel ratio to the stoichiometric air fuel ratio without performing the rich spike processing.

Control apparatus for an internal combustion engine

A particulate filter for trapping the particulate matter which is contained in the exhaust gas is provided inside an engine exhaust passage. Additional fuel is secondarily injected from a fuel injector in an engine expansion stroke or exhaust stroke or hydrocarbons are secondarily added from an addition valve which is provided upstream of the particulate filter in the exhaust pipe. An amount of hydrocarbons which come from the fuel injector or addition valve and then adhere in the form of a liquid to the inflow end of the particulate filter, and an amount of particulate matter which reaches the inflow end of the particulate filter are respectively estimated. A degree of clogging at the inflow end of the particulate filter is estimated based on the amount of hydrocarbons and the amount of particulate matter.

Exhaust purification system for internal combustion engine

An internal combustion engine is provided with a hydrocarbon feed valve arranged in an engine exhaust passage. When injection control for injecting hydrocarbons from the hydrocarbon feed valve for exhaust treatment is stopped, to prevent the hydrocarbon feed valve from clogging, hydrocarbons for preventing clogging are injected from the hydrocarbon feed valve when the engine is not discharging soot, that is, when the feed of fuel to the inside of the combustion chamber is stopped and, after hydrocarbons for preventing clogging are injected once, the injection of hydrocarbons for preventing clogging from the hydrocarbon feed valve is stopped until injection control for exhaust treatment is started.

Internal combustion engine

In an engine exhaust passage, in order from an exhaust upstream side, an NOstorage and reduction catalyst, NO oxidation catalyst, NOreduction catalyst, and selective reduction catalyst may be arranged. An air-fuel ratio of an exhaust gas which flows into the NOstorage and reduction catalyst may be temporarily switched to a rich air-fuel ratio which may be adapted for generating ammonia from NOwhich may be stored in the NOstorage and reduction catalyst. The ammonia, which may be generated by the NOstorage and reduction catalyst, may be held at the selective reduction catalyst. The NOwhich flows into the selective reduction catalyst may be reduced by the ammonia. The NO oxidation catalyst and NOreduction catalyst may be used to make an NO ratio of the exhaust gas which flows into the selective reduction catalyst approach an optimum ratio of the selective reduction catalyst.

A method for purifying exhaust gas of an internal combustion engine including flowing an exhaust gas containing NOand a concentration of hydrocarbons in an exhaust gas passage that contains an exhaust purification catalyst, wherein the concentration of hydrocarbons is vibrated within a predetermined range of amplitude and period, and a least a portion of the hydrocarbons are reformed by the exhaust purification catalyst; reacting the NOcontained in the exhaust gas and the reformed hydrocarbons to produce a reducing intermediate; and chemically reducing, wherein at the time of engine operation, a demanded produced amount of the reducing intermediate required for chemically reducing the NOis calculated, and the amplitude and vibration period of the concentration of hydrocarbons flowing into the exhaust purification catalyst are controlled so that an amount of the reducing intermediate produced becomes the demanded produced amount.

A temperature sensor includes temperature detecting means and at least one of a catalyst and an adsorbent applied to the surface of the temperature detecting means. At least one of the catalyst and the adsorbent catalyzes an exothermic reaction of a reactant in gas on the temperature detecting means. A temperature that is increased by the exothermic reaction is detected by the temperature detecting means. The catalytic efficiency for the exothermic reaction of at least one of the catalyst and the adsorbent is reduced by sulfur poisoning. The temperature sensor is disposed upstream of an exhaust purification system. Accordingly, it is determined that the temperature sensor is subjected to sulfur poisoning if the temperature detected by the temperature sensor is below a prescribed temperature.

Growing community of inventors

Susono, Japan

Kazuhiro Umemoto