Toyota Jidosha Kabushiki Kaisha

Takamitsu Asanuma

Shinya Hirota

Kohei Yoshida

Toshiaki Tanaka

Hiromasa Nishioka

Koichiro Nakatani

Koichi Kimura

Kazuhiro Itoh

Shunsuke Toshioka

Hiroshi Otsuki

Kenji Katoh

Akira Mikami

Kotaro Hayashi

Yasuaki Nakano

Satoshi Iguchi

Tetsuro Kihara

Shinichi Takeshima

Kazuhiro Umemoto

Yoshihisa Tsukamoto

Junichi Matsuo

Masato Gotoh

Yuka Nakata

Kiyoshi Nakanishi

Daichi Imai

Nobumoto Ohashi

Yoshimitsu Henda

Yuki Bisaiji

Makoto Ogiso

Tomihisa Oda

Hideyuki Nishida

Keiji Yoeda

Yoshihiro Iwashita

Takanori Ueda

Shouji Katsumata

Kazuhiko Shiratani

Yuichi Sobue

Tomomi Yamada

Fumitada Murakami

Masato Goto

Masao Watanabe

Hidetaka Nohira

Shizuo Sasaki

Hiroshi Okano

Tokuta Inoue

Hiroki Murata

Takao Fukuma

Takekazu Ito

Toshio Suematsu

Katsuhiko Oshikawa

Nobuyuki Takagi

Mikio Murachi

Jun Harada

Takeshi Inoguchi

Tetsuya Yamashita

Kazunobu Ishibashi

Masahiko Sugiyama

Kohei Igarashi

Shigenori Sakurai

Takayuki Endo

Kou Sugawara

Masahide Iida

Kenji Ohkubo

Yukihiro Tsukasaki

Morio Narita

Tadashi Watanabe

Masamichi Kuwajima

Souichi Matushita

Kouhei Yoshida

Masanori Takahashi

Kouji Toyoshima

Hiroyuki Nagareda

A fuel addition valve that adds fuel into the exhaust gas passage of the engine in the form of fine fuel droplets, an upstream NOx adsorption-reduction catalyst, and a downstream NOx adsorption-reduction catalyst are arranged in this order. Platinum Pt and palladium Pd, as noble metal, are supported on the downstream NOx adsorption-reduction NOx catalyst such that the ratio of the mole number of the platinum Pt to the sum of the mole numbers of the platinum Pt and the palladium Pd is approx. 50% to approx. 80%. Only platinum Pt is supported on the upstream NOx adsorption-reduction catalyst. According to this structure, even when liquid fuel is supplied into exhaust gas, NOx can be effectively released from the NOx adsorption-reduction catalyst, and further the amount of NOx that the NOx adsorption-reduction catalyst can adsorb at a low temperature increases.

Exhaust gas purification apparatus for internal combustion engine

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.

Temperature sensor, sulfur component detector, and exhaust purification system for internal combustion engine

An exhaust purification system of an internal combustion engine including an ammonia oxidation catalyst device and an ammonia holding device arranged immediately upstream of the ammonia oxidation catalyst device is provided. The ammonia holding device has a solid acid, holds ammonia to restrain the ammonia from flowing into the ammonia oxidation catalyst device when a temperature of the ammonia oxidation catalyst device is within a NO producing temperature range, and releases the held ammonia to make the ammonia flow into the ammonia oxidation catalyst device when the temperature of the ammonia oxidation catalyst device is out of the NO producing temperature range.

Exhaust purification system of internal combustion engine

In an internal combustion engine, inside of an engine exhaust passage, a hydrocarbon feed valve () and an exhaust treatment catalyst () are arranged. On a substrate () of the exhaust treatment catalyst (), a coat layer comprised of at least two layers of a top coat layer () and a bottom coat layer () is formed. The top coat layer () is comprised of an exhaust purification catalyst for reacting NOcontained in exhaust gas and reformed hydrocarbons, while the bottom coat layer () is comprised of an NOabsorption catalyst. The concentration of hydrocarbons which flows into the exhaust treatment catalyst () is made to vibrate within a predetermined range of amplitude and within a predetermined range of period. Due to this, NOcontained in exhaust gas and NOdesorbed from the NOabsorption catalyst () are reduced in the exhaust purification catalyst ().

In an internal combustion engine, inside of an engine exhaust passage, an NOadsorption part and an NOpurification part are arranged. The NOpurification part has the property of reducing NOwhich is contained in exhaust gas if the concentration of hydrocarbons is made to vibrate by within a predetermined range of amplitude and within a predetermined range of period. When NOis to be desorbed from the NOadsorption part, the current NOwhich is contained in the exhaust gas and the NOwhich is desorbed from the NOadsorption part are reduced by making the concentration of hydrocarbons of the NOpurification part vibrate by the amplitude and period which are set for the current engine operating state, at least of which (&#x394;T&#xb7;k) has been corrected so that the amount of hydrocarbons becomes greater.

In an exhaust gas purification apparatus of an internal combustion engine, there is provided a technique capable of suppressing a reduction in exhaust gas purification performance. The apparatus includes: an exhaust gas purification catalyst () that is arranged in an exhaust passage of the internal combustion engine for purifying an exhaust gas; an adsorption device () that is arranged at an upstream side of the exhaust gas purification catalyst, rises in temperature up to an upper limit temperature due to heat generated by adsorption thereto of an incoming first component, and falls in temperature after its temperature has reached said upper limit temperature; and a heat generating component supply unit () that supplies a second component which generates reaction heat in the exhaust gas purification catalyst, before the temperature of the adsorption device begins to fall.

Exhaust gas purification apparatus of an internal combustion engine

An exhaust purification system of an internal combustion engine includes an NOstorage reduction catalyst device which is arranged in an engine exhaust passage. The NOstorage reduction catalyst device stores SOsimultaneously with NO. When the stored SOamount exceeds a predetermined allowable amount, the SOis made to be released by SOrelease control which raises the temperature of the NOcatalyst device to the SOreleasable temperature, then makes the air-fuel ratio of the exhaust gas which flows into the NOcatalyst device the stoichiometric air-fuel ratio or rich. The NOcatalyst device has a residual SOstorage amount which finally remains even if performing SOrelease control depending on the temperature of the NOcatalyst device when performing SOrelease control. The system uses the residual SOstorage amount of the current SOrelease control as the basis to calculate the SOrelease speed at each timing in the current SOrelease control.

An internal combustion engine in which an SOtrap catalyst () for trapping SOcontained in the exhaust gas contains an oxygen adsorbing and releasing material () which can adsorb SOcontained in the exhaust gas and an SOstorage material () which can store SOin the form of sulfates. The SOwhich is contained in the exhaust gas is chemically adsorbed at the oxygen adsorbing and releasing material () without being oxidized. If the temperature of the SOtrap catalyst () becomes higher than the start temperature of adsorbed SOmovement, the SOwhich is chemically adsorbed at the oxygen adsorbing and releasing material () is oxidized and stored in the form of sulfates in the SOstorage material ().

In an internal combustion engine, an SOtrap catalyst () which traps SOcontained in the exhaust gas is arranged upstream of an NOstoring catalyst () in an engine exhaust passage. When the NOstoring catalyst () should release NO, auxiliary fuel is injected into a combustion chamber () at a combustible timing after the completion of injection of fuel into the combustion chamber () for generating the engine output. At this time, the auxiliary fuel is injected so that the air-fuel ratio A/F of the combustion gas in the combustion chamber () does not become below a minimum allowable air-fuel ratio M where SOtrapped at the SOtrap catalyst () will not be released.

Exhaust purification device of internal combustion engine

The present detector for detecting sulfur components includes a storage portion for storing SOand NOin the exhaust gas passing through an exhaust passage, in which the more an amount of stored SOincreases, the more an amount of stored NOdecreases, and which does not release SObut release NOat a set temperature, and a temperature sensor, estimates the amount of stored SOon the basis of a relationship between, after the storage portion becomes the set temperature by heating, a heating pattern of the storage portion and temperature change of the storage portion measured by the temperature sensor, and detects an integrated amount of SOpassing through the exhaust passage during a given period or an value on the basis of the integrated amount.

Detector for detecting sulfur components

An internal combustion engine in an engine exhaust passage of which an NOadsorption catalyst () adsorbing NOcontained in exhaust gas at the time of a low temperature and desorbing the adsorbed NOwhen the temperature rises and an NOstorage catalyst () are arranged. When the NOstorage catalyst () can store NO, the temperature of the NOadsorption catalyst () is made to forcibly rise to a target temperature at which the amount of NOwhich the NOstorage catalyst () can store is desorbed, and the NOdesorbed from the NOadsorption catalyst () is stored in the NOstorage catalyst ().

An exhaust purification system is provided with an NOstorage reduction catalyst arranged in an exhaust passage and an SOtrap material arranged upstream of the NOstorage reduction catalyst and removes SOcontained in exhaust gas. A main flow path has a secondary flow path connected to it. In the secondary flow path, a removal device is arranged for removing the sulfur constituent contained in fuel. The secondary flow path includes an opening and closing device. When the SOremoval rate of the SOtrap material becomes a predetermined removal rate judgment value or less or the concentration of the SOwhich flows into the SOtrap material becomes a predetermined concentration judgment value or more, at least part of the fuel flowing through a main flow path is made to flow into the secondary flow path and run through the removal device.

An electronic control unit executing an algorithm so as to operate an exhaust purification system of an engine. The algorithm (1) commences a regeneration treatment by causing an amount of fuel supplied to a combustion process of the engine to increase so as to change an air-fuel ratio of exhaust gas of the engine from a first lean air-fuel ratio to a set rich air-fuel ratio and (2) causes uncombusted fuel to be supplied to a NOx catalyst device during at least one of: a first period in which an air-fuel ratio of the exhaust gas within the NOx catalyst device changes from the first lean air-fuel ratio to the set rich air-fuel ratio when the regeneration treatment is started; and a second period after an air-fuel ratio of the exhaust gas within the NOx catalyst device becomes a ratio indicating completion of the regeneration treatment.

In an internal combustion engine, an NOselective reduction catalyst () is arranged in an engine exhaust passage, and an NOstorage catalyst () is arranged in the engine exhaust passage upstream of the NOselective reduction catalyst (). When the amount of NOstored in the NOstorage catalyst () exceeds a predetermined allowable value, the NOstorage catalyst () is raised in temperature to make the NOstorage catalyst () release the NO. The amount of urea feed is decreased by exactly the amount of reduction of the calculated stored NOamount with respect to the amount of urea feed determined from the engine operating state, and the amount of urea feed is increased by exactly the amount of reduction of the calculated released NOamount with respect to the amount of urea feed determined from the engine operating state.

An SOtrap catalyst able to trap SOcontained in the exhaust gas is arranged in an engine exhaust passage upstream of an NOstoring catalyst in an internal combustion engine. When the SOtrap rate of the SOtrap catalyst falls, fuel is added in the exhaust gas flowing into the SOtrap catalyst to form in the SOtrap catalyst a region in which an air-fuel ratio becomes locally rich. SOreleased from the SOtrap catalyst in this region can be trapped in the SOtrap catalyst at the downstream side once again without flowing out from the downstream end of the SOtrap catalyst.

Growing community of inventors

Mishima, Japan

Takamitsu Asanuma