Honda Giken Kogyo Kabushiki Kaisha

Other

Honda Motor Co., Ltd.

Nippon Chemical Industrial Co., Ltd.

Kyowa Hakko Bio Co., Ltd.

Tetsuo Endo

Masaki Ueno

Shiro Takakura

Masahiro Sato

Hideharu Yamazaki

Kei Machida

Yuji Yasui

Yoshihisa Iwaki

Tadashi Sato

Takashi Haga

Haruhiko Shimizu

Takahiro Naka

Yasuyuki Miyahara

Norihito Watanabe

Shusuke Akazaki

Yoshikazu Fujisawa

Kenji Abe

Satoshi Koizumi

Kenichi Ohmori

Yuichi Matsuo

Yoshiaki Hatakeyama

Naohiro Sato

Tadashi Satoh

Shinichi Kikuchi

Hiroshi Ogasa

Muneo Mita

Shinya Ishimaru

Go Motohashi

Robert V Tompson, Jr

Osami Yamamoto

Tushar K Ghosh

Masao Komine

Mitsuo Wakabayashi

Chiaki Seki

Hiroki Hosoe

Sudarshan Loyalka

Shun Kato

Hiroki Takeori

George Vosnidis

Gregory A Holscher

Kenji Agemoto

An exhaust-gas purification system of an internal combustion engine includes an electrically heated catalytic device and a three-way catalytic device. The electrically heated catalytic device includes a first honeycomb base having a large number of honeycomb passages and a first catalyst component that is supported on, by a predetermined thin-film treatment, surfaces that define the honeycomb passages and that contains one or more types of noble metals. The three-way catalytic device includes a second honeycomb base having a large number of honeycomb passages and a second catalyst component that is supported on surfaces defining the honeycomb passages and that contains one or more types of noble metals. The total noble metal content per unit volume of the second honeycomb base is higher than the total noble metal content per unit volume of the first honeycomb base.

Exhaust-gas purification system of internal combustion engine

An internal combustion engine HC-adsorbent is located in one of a pair of exhaust passages in parallel to each other downstream of an emission control catalyst for purifying an exhaust gas and through which exhaust gas flows selectively by a switchover valve. The adsorbent is a zeolite mixture having pores at least 3.5 &#x212b; and smaller than 6 &#x212b; and not equal or larger than 6 &#x212b; and smaller than 7 &#x212b;, and zeolite having pores at least 7 &#x212b; and smaller than 10 &#x212b; and not equal or larger than 6 &#x212b; and smaller than 7 &#x212b;. HCs are desorbed quickly and easily lowering the desorption temperature, while ensuring excellent adsorbing performance for HCs of different molecular diameters. Even when a vehicle travels only a short duration after engine starting, desorption advances quickly and reliably, the adsorbent exhibiting intended adsorbing performance at the next engine starting.

HC-adsorbent for internal combustion engine

A temperature control apparatus for a humidity sensor is provided for preventing impurities from sticking on a sensor element, while protecting the sensor element from cracking due to the humidity sensor heated by a heater in the presence of condensation, to maintain a high detection accuracy of the humidity sensor. The temperature control apparatus is configured to control the temperature of a sensor element of a humidity sensor disposed in an exhaust passage of an internal combustion engine for detecting the humidity within the exhaust passage. The temperature control apparatus comprises a heater for heating the sensor element, a temperature sensor for detecting the temperature of the sensor element, and an ECU for controlling a heating amount of the heater to bring the detected temperature of the sensor element to a first predetermined temperature during an operation of the internal combustion engine.

Temperature control apparatus for humidity sensor

A humidity sensoris disposed downstream of an exhaust gas purifier comprising a hydrocarbon adsorbing catalyst, and an air-fuel ratio sensoris disposed at least downstream of the exhaust gas purifier. The hydrocarbon adsorbing ability of a hydrocarbon adsorbent of a hydrocarbon adsorbing catalyst(the exhaust gas purifier) is evaluated using output data of the humidity sensor. The unburned gas purifying ability based on a catalytic action of the hydrocarbon adsorbing catalystis evaluated using output data of the air-fuel ratio sensor. Based on the evaluated results, the overall deteriorated state of the exhaust gas purifier is evaluated. The overall deteriorated state of the exhaust gas purifier which has the hydrocarbon adsorbing catalystcan thus adequately be evaluated.

Deteriorated state evaluation device for exhaust emission control equipment

A characteristic change of a humidity sensoris detected based on the transitional characteristics of output data of the humidity sensorwith respect to integrated moisture quantity data representative of an integrated amount of moisture that is supplied to an HG adsorbentby an exhaust gas after an enginehas started to operate. A parameter for grasping a state of the HC adsorbentis corrected. The state, such as a deteriorated state or the like, of a hydrocarbon adsorbent (HC adsorbent) is properly monitored while compensating for the effect of the characteristic change of the humidity sensor and the effect of variations of the characteristics of individual units of the humidity sensor.

Hydrocarbon adsorbent state monitoring device

A hydrocarbon adsorbent state determining apparatus is provided for compensating the ability of a hydrocarbon adsorbent to adsorb moisture for fluctuations due to a change in the flow velocity of exhaust gases to accurately determine the state of the hydrocarbon adsorbent, including a deterioration thereof, irrespective of the change in the flow rate of exhaust gases. The hydrocarbon adsorbent state determining apparatus determines the state of a hydrocarbon adsorbent disposed in an exhaust system of an internal combustion engine for adsorbing hydrocarbons and moisture within exhaust gases. The hydrocarbon adsorbent state determining apparatus comprises a downstream humidity sensor for detecting the humidity of exhaust gases which have passed through the hydrocarbon adsorbent, a flow velocity parameter detector for detecting a flow velocity parameter indicative of a flow velocity of the exhaust gases, and an ECU for determining the state of the hydrocarbon adsorbent in accordance with the detected humidity of the exhaust gases and the flow velocity parameter.

Hydrocarbon adsorbent state determining apparatus

A temperature sensor is disposed near an HC adsorbent in an exhaust system of an internal combustion engine. After the internal combustion engine is shut off, a deteriorated state of the HC adsorbent is evaluated based on a value of the humidity detected by a humidity sensor. The deteriorated state of the HC adsorbent is evaluated by comparing the detected value of the humidity with a threshold established depending on the temperature state near the HC adsorbent. In evaluating deteriorated state of the HC adsorbent, a change in the output characteristics of the humidity sensor depending on its temperature state is compensated for.

Method of evaluating deteriorated state of hydrocarbon adsorbent

After an internal combustion engine has started to operate, a changing timing is detected at which a humidity represented by the output signal of a humidity sensor disposed downstream of a hydrocarbon adsorbent changes to a tendency to monotonously increase from a low humidity to a high humidity. Data representing a total amount of moisture carried by an exhaust gas emitted by the internal combustion engine to the hydrocarbon adsorbent up to the changing timing is acquired as a deterioration evaluating parameter. The deteriorated state of the hydrocarbon adsorbent is evaluated based on the deterioration evaluating parameter. The changing timing is detected as a timing at which the relative humidity represented by the output signal of the humidity sensor has changed from a low humidity to a high humidity by a preset value. The preset value is variably set in order to compensate for characteristic changes of the humidity sensor and variations of individual humidity sensors. The deteriorated state of the hydrocarbon adsorbent can thus adequately be monitored while compensating for the characteristic changes of the humidity sensor and the variations of individual humidity sensors.

Apparatus for evaluating deteriorated state of hydrocarbon adsorbent

An exhaust gas valve device in an internal combustion engine, including a first bearing member mounted between a valve shaft and a valve body with one end of the valve shaft turnably fitted into the first bearing member, a second bearing member mounted between the valve shaft and the valve body with the other end of the valve shaft turnably passed through the second bearing member, and an actuator connected to the other end of the valve shaft protruding from the second bearing member. The valve body, the valve shaft and the first and second bearing members are formed of metal materials having equivalent thermal expansion coefficients; the first and second bearing members are press-fitted into said valve body; and a skin of a graphite-based solid lubricant is formed on a surface of the valve shaft in regions corresponding to the first and second bearing members. The concentricity accuracy of the pair of bearing members supporting the opposite ends of the valve shaft is enhanced, while avoiding an increase in the number of parts, thereby preventing the generation of noise and reducing the friction.

Exhaust gas valve device in internal combustion engine

A catalyst state detector for detecting a state of an exhaust gas purifying catalyst which is capable of accurately detecting the state, including deterioration, of an HC adsorbent contained in the exhaust gas purifying catalyst for adsorbing hydrocarbons in exhaust gases of an internal combustion engine, and can be manufactured at a low cost. The exhaust gas purifying catalyst is arranged at an intermediate portion of an exhaust pipe, and the HC adsorbent is capable of adsorbing hydrocarbons and moisture in exhaust gases. The catalyst state detector comprises a downstream humidity sensor arranged at a location downstream of the HC adsorbent in the exhaust pipe for detecting a humidity of the exhaust gases, and an adsorbent state detecting unit (ECU) for detecting the state of the HC adsorbent in accordance with the result of detection made by the downstream humidity sensor.

Catalyst state detector for exhaust gas purifying catalyst

A state determining apparatus for an exhaust gas purifier is provided for determining the state of the exhaust gas purifier including an adsorbent for adsorbing hydrocarbons; in accordance with the temperature state in the exhaust system of an internal combustion engine. The state determining apparatus is arranged in an exhaust system of the internal combustion engine. The state determining apparatus comprises a humidity sensor for detecting the humidity within a bypass exhaust pipe, and an ECU for determining the temperature state of the exhaust system and determining the state of adsorbent in accordance with the humidity within the bypass exhaust pipe detected by the humidity sensor and the temperature state in the exhaust system detected by the ECU.

State determining apparatus for exhaust gas purifier

An adsorbent deterioration determining apparatus can accurately determine a deterioration of an adsorbent in a relatively simple configuration. The adsorbent deterioration determining apparatus determines a deterioration of an adsorbent arranged in an exhaust system of an internal combustion engine for purifying exhaust gases. The adsorbent is capable of adsorbing hydrocarbons and moisture in exhaust gases. The adsorbent deterioration determining apparatus comprises a humidity sensor arranged at a location downstream of the adsorbent in the exhaust system for detecting the humidity of exhaust gases, and an ECU for determining a deterioration of the adsorbent in accordance with a detected output of the humidity sensor at the time a predetermined time has elapsed from a start of the internal combustion engine.

Adsorbent deterioration determining apparatus

An adsorbent for HC in an exhaust gas is an agglomerate of double-structure particles, each of which includes an HC-adsorbing zeolite core, and a ceramic coat wrapping the zeolite core and having a plurality of through-pores communicating with a plurality of pores in the zeolite core. Each of the double-structure particles is at least one of a double-structure particle including the zeolite core comprising a single zeolite particle, and a double-structure particle including the zeolite core comprising a plurality of zeolite particles. Each of the through-pores in the ceramic coat has such a shape that the HC is easy to flow into the through-pore and difficult to flow out of the through-pore.

Adsorbent for HC in exhaust gas, and process for producing the same

There are provided an adsorption amount sensor which is capable of accurately detecting an amount of hydrocarbons or water adsorbed by a zeolite of a hydrocarbon adsorber, even during operation of an engine, as well as a coking sensor which is capable of accurately detecting an amount of coke deposition on inner surfaces of a pipe of an internal combustion engine, even during operation of an engine. The adsorption amount sensor has a plurality of electrodes arranged in the vicinity of the hydrocarbon adsorber in a manner opposed to each other and each carrying a zeolite thereon. The amount of hydrocarbons adsorbed is detected by using a parameter indicative of changes in at least one of a resistance value between the electrodes and an electrical capacitance between the electrodes. The coking sensor has a plurality of electrodes arranged within the pipe of the engine in a manner opposed to each other and each having a surface thereof coated with an insulating material. The amount of coke deposition is detected by using a parameter indicative of changes in at least one of a resistance value between the electrodes and an electrical capacitance between the electrodes.

Adsorption amount sensor and coking sensor for internal combustion engine

An exhaust system comprising a heat-resistant HC adsorbent comprising an MFI metallo-silicate including at least one of gallium (Ga) and indium (In) as a skeleton forming element, and a metal component ME including at least one of an alkali metal and an alkali earth metal in a content of ME&lE;0.05% by weight. Such an HC adsorbent has an excellent heat resistance.

Exhaust system comprising a heat-resistant HC adsorbent

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Wako, Japan

Tetsuo Endo