Honda Giken Kogyo Kabushiki Kaisha

Honda Motor Co., Ltd.

Hideharu Yamazaki

Masaki Ueno

Kei Machida

Tetsuo Endo

Takashi Haga

Masahiro Sato

Shusuke Akazaki

Hiroyuki Goto

Yoshihisa Iwaki

Tadashi Sato

Yasuyuki Miyahara

Akifumi Otaka

Shiro Takakura

Katsuhiko Kohyama

Yuji Yasui

Kenji Hirose

Kazuhiro Kobayashi

Takeaki Nakajima

Shinya Murabayashi

Shukoh Terata

Tadashi Satoh

Shoichi Hokazono

Toshihiro Kameda

Takuji Yamamoto

Katsumi Saito

Takeshi Kumakura

Yoshihito Sakurai

Hiroyoshi Hayakawa

Masaaki Hasegawa

Yoshihiro Kuki

Tetsuhiro Okada

A vehicle fuel supply device including a saddle-shaped fuel tank comprised of a main chamber and an auxiliary chamber. A reservoir is disposed within the main chamber. A main pump is provided within the reservoir. A sub-pump is detachably provided within the reservoir. The fuel in the reservoir is drawn up by an operation of the main pump to supply fuel to an engine. A portion of the drawn-up fuel is utilized to generate a negative pressure, the negative pressure is utilized to transfer the fuel in the auxiliary chamber to the reservoir, and the negative pressure is utilized to introduce the fuel in the main chamber into the reservoir.

Vehicle fuel supply device

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 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

An exhaust gas purification system of an internal combustion engine having a bypass exhaust gas passage, openable through a switch-over valve, branched from an exhaust pipe at a location downstream of a catalytic converter and again merged into the exhaust pipe at a downstream point, an adsorbent installed in the bypass exhaust gas passage which adsorbs unburned component of the exhaust gas, and an EGR pipe which recirculates the exhaust gas including the unburned components at a location upstream of the catalytic converter, wherein the EGR pipe is made of metal such as stainless steel and is connected to the bypass exhaust gas passage such that the recirculation pipe is brought into thermal contact with the exhaust pipe, thereby enabling to effectively prevent blocking or corrosion of the EGR pipe or switch-over valve from occurring. The inner wall of the recirculation pipe is formed with liquid repellent and oil repellent film so as to overcome moisture-related problems more effectively.

Exhaust gas purification system of internal combustion engine

A state determination apparatus for a humidity sensor is provided for accurately determining the state of the humidity sensor, including the responsibility, from a result detected by the sensor itself. The state determining apparatus is configured to determine a humidity sensor arranged in an exhaust system of an internal combustion engine for detecting a humidity within an exhaust pipe. The apparatus comprises an ECU which determines whether or not the internal combustion engine is in a predetermined operating condition, calculates a change state parameter indicative of a change state of a value detected by the humidity sensor based on the detected value of the humidity sensor detected when the internal combustion engine is in the predetermined operating condition, and determines the state of the humidity sensor in accordance with the calculated change state parameter.

State determining apparatus for humidity sensor

An adsorbent state determining apparatus is provided for accurately determining the state of an adsorbent including a deterioration while ensuring elimination of the influence of impurities sticking on a sensor element of a humidity sensor. The adsorbent state determining apparatus determines the state of an adsorbent disposed in an exhaust system of an internal combustion engine for purifying exhaust gases. The adsorbent is capable of adsorbing hydrocarbons and moisture within exhaust gases. The adsorbent state determining apparatus comprises a humidity sensor disposed near the adsorbent in the exhaust system for detecting a humidity of exhaust gases; a heater for executing cleaning for removing impurities sticking on a sensor element of the humidity sensor; and an ECU for determining whether or not the heater has completed the cleaning, and for determining the state of the adsorbent in accordance with the humidity of exhaust gases detected by the humidity sensor when the ECU determines that the cleaning is completed.

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

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 temperature estimating apparatus for an internal combustion engine is provided for correctly calculating the temperature of an exhaust device even when the internal combustion engine is started under low temperature conditions. The temperature estimating apparatus comprises an ECU for estimating the temperature of a hydrocarbon adsorbent in an exhaust system of the internal combustion engine through calculations. The ECU calculates an estimated adsorbent temperature of the adsorbent in accordance with an engine rotational speed, an absolute intake pipe inner pressure, an engine water temperature, an intake temperature, and a detected humidity of exhaust gases. This calculation is started when condensation, which has occurred within an intake pipe, is eliminated.

Temperature estimating apparatus for internal combustion engine

There is provided a temperature control system for a humidity sensor, which is capable of eliminating impurities attached to a sensor element of the sensor efficiently and sufficiently while preventing the sensor element from being cracked due to heat generated by a heater in a state of condensation formed thereon, and suppressing attachment of impurities to the sensor element, thereby making it possible to preserve an excellent detection accuracy of the humidity sensor. The temperature control system controls the temperature of the sensor element of the humidity sensor arranged in an exhaust pipe for detecting humidity within the exhaust pipe. A heater heats the sensor element. The temperature of the sensor element is detected. When the detected temperature of the sensor element is higher than a predetermined temperature, said heater is operated.

Temperature control system for humidity sensor

A first cutoff valve and a second cutoff valve are closed in a state in which an internal combustion engine is stopped, and a reducing amount of a pressure P in a high pressure passageway after the passage of a predetermined decision time T and a reducing amount of a pressure P in a low pressure passageway after the passage of a predetermined decision time T are measured. When the reducing amount of the first pressure P is equal to or larger than a predetermined reducing amount &Dgr;P , it is decided that a leakage is generated in the high pressure passageway . When the reducing amount of the second pressure P is equal to or larger than a predetermined reducing amount &Dgr;P , it is decided that a leakage is generated in the low pressure passageway

Fuel gas feeding system

A vehicle fuel gas supply system includes, a fuel line supplying a fuel gas to a gas engine, a shut-off valve and a pressure sensor disposed on said fuel line, and a control section. The pressure sensor is disposed closer to the gas engine in comparison with the shut-off valve. The control section closes the shut-off valve based on a failure diagnostic signal, calculates a pressure drop rate based on pressure information taken in from the pressure sensor after the closure of the shut-off valve and an elapsed time, and judges that the shut-off valve is in a failure state when the pressure drop rate so calculated is smaller than a predetermined pressure drop rate threshold value.

Vehicle fuel gas supply system

A vehicle fuel gas supply system includes a fuel line supplying a fuel gas to a gas engine, a shut-off valve and a pressure sensor disposed on said fuel line, and a control section. The pressure sensor is disposed closer to said gas engine in comparison with said shut-off valve. The control section closes the shut-off valve being opened, starts to count the time of a shut-off valve closing timer. Then, the control section opens the shut-off vale when the shut-off valve closing timer counts up, simultaneously therewith measures a pressure by the pressure sensor to store the pressure as an initial pressure, and starting to count the time of a diagnostic timer. Further, the control section measures a second pressure by the pressure sensor when the diagnostic timer counts up to store the second pressure as a final pressure value, and judges that the shut-off value is in a failure state when a pressure increase rate obtained from the initial pressure value and the final pressure value is smaller than a predetermined pressure increase rate threshold value.

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Saitama-ken, Japan

Hideharu Yamazaki