Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A first cutoff valve 24 and a second cutoff valve 41 are closed in a state in which an internal combustion engine 1 is stopped, and a reducing amount of a pressure P0 in a high pressure passageway 11 after the passage of a predetermined decision time T0 and a reducing amount of a pressure P2 in a low pressure passageway 12 after the passage of a predetermined decision time T2 are measured. When the reducing amount of the first pressure P0 is equal to or larger than a predetermined reducing amount &Dgr;P0, it is decided that a leakage is generated in the high pressure passageway 11. When the reducing amount of the second pressure P2 is equal to or larger than a predetermined reducing amount &Dgr;P2, it is decided that a leakage is generated in the low pressure passageway 12.

Abstract: 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.

Abstract: 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.

Abstract: A first cutoff valve 24 and a second cutoff valve 41 are closed in a state in which an internal combustion engine 1 is stopped, and a reducing amount of a pressure P0 in a high pressure passageway 11 after the passage of a predetermined decision time T0 and a reducing amount of a pressure P2 in a low pressure passageway 12 after the passage of a predetermined decision time T2 are measured. When the reducing amount of the first pressure P0 is equal to or larger than a predetermined reducing amount &Dgr;P0, it is decided that a leakage is generated in the high pressure passageway 11. When the reducing amount of the second pressure P2 is equal to or larger than a predetermined reducing amount &Dgr;P2, it is decided that a leakage is generated in the low pressure passageway 12.

Abstract: A super magnetostrictive actuator includes: a magnetic field generating unit, at least first and second super magnetostrictive members extensible in a longitudinal direction thereof due to action of magnetic field generated by the magnetic field generating unit, and a coupling member having a cylindrical shape and disposed coaxially between the first and second super magnetostrictive members. The second super mangetostrictive member has a cylindrical shape and is coaxially disposed to surround the outside of the first super magnetostrictive member in a radial direction thereof. Both end portions of the coupling member are coupled to one end portion of the first super magnetostrictive member and one end portion of the second super magnetostrictive member, respectively.

Abstract: 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.

Abstract: 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.

Abstract: A combustion chamber component for an internal combustion engine has a water and oil repellent coating which has good adhesive power and in which the effect of suppressing the accumulation of deposits is well maintained. The coating is formed from an organosilicon compound represented by the formula Rf—R1—Si(NH)3/2 wherein Rf denotes a perfluoroalkyl group having 1 to 10 carbon atoms and R1 denotes a divalent hydrocarbon group having 2 to 10 carbon atoms.

Abstract: A system for detecting malfunctions of an exhaust switch-over valve of an internal combustion engine, which opens/closes a bypass exhaust gas passage branched from an exhaust pipe of the engine and storing an adsorbent that adsorbs unburned components of the exhaust gas generated by the engine when the engine is started. In the system, the entrance temperature and the exit temperature in the bypass exhaust gas passage are detected and compared with each other in a first detection period when the passage is opened and in a second detection period when the passage is closed. Based on this comparison, it is determined whether the valve malfunctions. Alternatively, the valve malfunction is determined by comparing the valve opening/closing state with an instruction to operate the valve. With this, little time lag exists in the detection, thereby improving malfunction detection accuracy.

Abstract: A pump has a rotor made of synthetic resin in a fixed housing which are adjacently arranged while forming a gap between the housing and the rotor to force-feed a medium containing water moisture, in which the rotor is made of a resol-type synthetic resin so that a dimensional change rate of the rotor is 0.15% or less for a medium having a moisture content rate of 10 wt % or less, whereby a sufficient pump performance can be obtained while relatively increasing the degree of freedom of the moisture content rate of the medium to reduce the corrosiveness of the medium.