Abstract: A reduction gear for forming a geared motor having a motor and a reduction gear is provided. The reduction gear for a geared motor includes an intermediate orthogonal gear head having an orthogonal transfer mechanism for changing a rotational direction of power delivered from the motor into an orthogonal direction and houses the orthogonal transfer mechanism in a separate intermediate casing. The reduction gear further includes a rear stage parallel gear head having a parallel shaft reduction mechanism including an output shaft serving as a final output shaft of the geared motor when the geared motor is formed, the rear stage parallel gear head being capable of directly connecting to a rear stage of the intermediate orthogonal gear head, with the parallel shaft reduction mechanism being housed in a separate rear stage casing.

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. When the detected temperature of the sensor element is higher than a predetermined temperature, said heater is operated.

Abstract: 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.

Abstract: A failure determination device that detects the humidity of exhaust gases from an internal combustion engine and a control system for an exhaust passage changeover valve, which can switch the changeover valve with appropriate timing, thereby enabling sufficient purification of exhaust gases. An operating condition of the engine is detected. Based on the detected operating condition of the engine, it is determined whether the engine is in an operating condition in which failure determination of the humidity sensor can be executed. It is determined whether the humidity sensor has failed, based on a result of detection by the humidity sensor, when it has been judged that the failure determination of the humidity sensor can be executed.

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: 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.

Abstract: An exhaust gas purification system of internal combustion engine having a branch pipe coupled to the exhaust pipe through a flange and having a first cylindrical case constituting a bypass exhaust gas passage and a second cylindrical case constituting a main exhaust gas passage, whose flow are switched by a switch-over valve by selectively connecting the exhaust pipe to the main exhaust gas passage or the bypass exhaust gas passage, and an adsorbent installed in the bypass exhaust gas passage for adsorbing unburned components of the exhaust gas. The unburned exhaust gas components are recirculated to the air intake system through an EGR pipe. In the system, an inlet of the EGR pipe is formed integrally with the branch pipe flange, thereby enabling to prevent increase in fabrication step and cost and further to facilitate maintenance. Moreover, the first cylindrical case is made displace relative to the second cylindrical case.

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 simple planetary gear mechanism is provided with an automatic alignment function to support the planet gear to obtain a speed reducer having reduced backlash by a simple method. A planet gear is supported by a carrier pin that is in turn supported by a carrier. The carrier pin includes a crank portion that is eccentric by “e” relative to the axis center of the carrier pin with the eccentric angle being made variable. The planet gear is supported rotatably about the axis center of the crank portion. Consequently, with the eccentric angle being made variable, the axis center of the planet gear is automatically aligned in the radial direction upon assembly of each gear, thereby making it possible to minimize backlash only by incorporating a sun gear having a proper dimension.

Abstract: There are provided a failure determination device simple in construction and capable of properly determining failure of a humidity sensor that detects the humidity of exhaust gases from an internal combustion engine and a control system for an exhaust passage changeover valve, which can switch the changeover valve with appropriate timing, thereby enabling sufficient purification of exhaust gases. In one form of the invention, an operating condition of the engine is detected. It is judged based on the detected operating condition of the engine whether or not the engine is in an operating condition in which failure determination of the humidity sensor can be executed. It is determined whether or not the humidity sensor has failed, based on a result of detection by the humidity sensor, when it has been judged that the failure determination of the humidity sensor can be executed.

Abstract: A system for purifying exhaust gas generated by an internal combustion engine having an adsorbent, installed in an exhaust system of the engine, which adsorbs unburned components of the exhaust gas such as hydrocarbons generated by the engine. The system has a first temperature sensor for detecting a temperature of the adsorbent and timer for measuring a time until the detected temperature becomes greater or equal to a predetermined value, when the measured time is less than a threshold value, it is discriminated that the adsorbent deteriorates. With this, the deterioration of the adsorbent can be discriminated accurately.

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 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 system for purifying exhaust gas generated by an internal combustion engine including a bypass branching out from the exhaust pipe downstream of a catalyst and merging to the exhaust pipe, an adsorber installed in the bypass, a bypass valve member which closes the bypass, and an EGR conduit connected to the bypass at one end and connected to the air intake system for recirculating the exhaust gas to the air intake system. The bypass valve member is opened for a period after engine startup to introduce the exhaust gas such that the adsorber installed in the bypass adsorbs the unburnt HC component in the exhaust gas. The adsorber adsorbs the HC component when the exhaust temperature rises and the adsorbed component is recirculated to the air intake system through the EGR conduit. In the system, the bypass valve is provided at or close to the branching point in the exhaust pipe and a chamber is provided close to the branching point such that the conduit is connected to the bypass at the one end in the chamber.

Abstract: An air-fuel ratio control system for an internal combustion engine having a fuel injection valve for each cylinder and an electronic air control valve (EACV) for controlling intake air bypassing the engine throttle valve. When the target air-fuel ratio is switched over from a rich value to a lean value, the amounts of fuel injected into the cylinders, for example, #1, #2, #3 and #4 cylinders are controlled so that they are sequentially decreased at predetermined intervals, and the EACV is controlled to be opened stepwise. This causes a decrease in engine torque generated by the switching-over of the target air-fuel ratio to be offset by an increase in engine torque generated by an increase in amount of air drawn, thereby preventing the generation of a torque shock. At this time, the target opening degree of the EACV is corrected based on the magnitude of the interval and the magnitude of a loading of the internal combustion engine, thereby further effectively preventing the generation of the torque shock.

Abstract: The eccentric body shaft bearing holes, the eccentric body bearing holes and the carrier pin holding holes are set to satisfy the following relationship. Namely, when the first and second supporting blocks and the externally toothed gears are appropriately rearranged in the axial positions thereof, the diameters of the eccentric body shaft bearing holes and the diameters of the eccentric body bearing holes become smaller toward one direction. Also, while keeping the above rearrangement, the diameters of the carrier pin holding holes become smaller in the same direction. The outside diameter of the first and second supporting blocks is set to be smaller than the root diameter of the external teeth of each externally toothed gear.

Abstract: A control system for an internal combustion engine adjusts at least one predetermined control parameter such that a rate of combustion variation calculated based on a detected state of combustion of the engine becomes equal to a desired rate of combustion variation, which is dependent on operating conditions of the engine. A state of engagement of a lock-up clutch connected to the engine and a slip ratio of a torque converter connected to the same are detected. The desired rate of combustion variation is corrected in dependence on at least one of the detected state of engagement of the lock-up clutch and the detected slip ratio of the torque converter.

Abstract: The eccentric body shaft bearing holes, the eccentric body bearing holes and the carrier pin holding holes are set to satisfy the following relationship. Namely, when the first and second supporting blocks and the externally toothed gears are appropriately rearranged in the axial positions thereof, the diameters of the eccentric body shaft bearing holes and the diameters of the eccentric body bearing holes become smaller toward one direction. Also, while keeping the above rearrangement, the diameters of the carrier pin holding holes become smaller in the same direction. The outside diameter of the first and second supporting blocks is set to be smaller than the root diameter of the external teeth of each externally toothed gear.

Abstract: In a control system for controlling a gear ratio of a multi-step geared or continuously variable automatic transmission, the driver's intention to decelerate is inferred by carrying out a first fuzzy reasoning using a degree of throttle opening or the like and then the target gear ratio is determined by carrying out a second fuzzy reasoning using parameters including the inferred driver's intention to decelerate. The first fuzzy reasoning is carried out using fuzzy production rules classified by operating conditions such as a road profile and a vehicle speed. The inferred driver's intention to decelerate is canceled if braking is discontinued. Thus the control ascertain the intention of the driver and is thus possible to achieve sophisticated shift scheduling well matched to the sensibilities of the driver.