Abstract: A secondary air supply system includes an exhaust gas control catalyst which is provided in an exhaust system in an internal combustion engine, and which purifies a harmful component in exhaust gas; a secondary air supply device which supplies secondary air into the exhaust gas upstream of the exhaust gas control catalyst; a secondary air supply stop device which stops the secondary air supply performed by the secondary air supply device; a fuel supply device which supplies fuel to the internal combustion engine; a fuel amount increasing device which increases a fuel amount supplied to the internal combustion engine during the secondary air supply; and a fuel amount increase stop time delaying device which delays, by a predetermined delay period, a stop time at which the increase in the fuel amount caused by the fuel amount increasing device is stopped even when the secondary air supply is stopped.

Abstract: An anomaly judgment apparatus for a secondary air supply system which includes a secondary air supply path for introducing secondary air from an intake path of an engine into an exhaust path at a location upstream of a catalytic converter disposed in the exhaust path. The apparatus includes a pressure detector for detecting pressure in the secondary air supply path, and an anomaly judgment section for calculating pulsation level indicative of the degree of pulsation of pressure detected by the pressure detector and for judging, on the basis of at least the pulsation level, whether or not the secondary air supply system is anomalous. The apparatus further includes an anomaly judgment prohibiting section for prohibiting judgment by the anomaly judgment section when the degree of propagation of intake air pulsation arising in the intake path into the secondary air supply path is equal to or higher than a predetermined level.

Abstract: When the determination result of failure determination at a start of AI (auxiliary air injection=supply) is that there is a possibility of a closing anomaly due to freezing, a reevaluation process 1 being a reevaluation after a warm-up is performed. When the determination result of determination at an end of AI is that there is a possibility of an opening anomaly due to freezing, a reevaluation process 2 being a reevaluation after a warm-up is performed.

Abstract: The invention relates to a secondary air feeding apparatus and a method of detecting an abnormality in the apparatus capable of making a precise determination on abnormalities in components and detecting operational failures as well. According to one aspect of the invention, the opening-closing state of opening-closing means (ASV) is switched during the operation of an air pump, and abnormalities in respective components are detected on the basis of pressure values and pressure fluctuation values detected by a pressure sensor disposed between the air pump and the ASV before and after the switching of the opening-closing means.

Abstract: An internal combustion engine includes an air pump that supplies secondary air to an upstream side of an exhaust gas control catalyst in an exhaust pipe via a secondary air supply passage; an adjusting device that adjusts an intake air amount delivered into a combustion chamber from an intake pipe; and a controller that performs control for increase correction of the intake air amount adjusted by the adjusting device when the air pump performs an operation of supplying the secondary air. Thus, it is possible to prevent a problem caused by a reduction in an engine speed due to the secondary air supply.

Abstract: A secondary air supplying apparatus of the present invention comprises a secondary air supplying device for supplying secondary air to upstream of an emission purifying device in an exhaust system of an internal combustion engine, a coolant temperature sensor for detecting a temperature of a coolant for the engine, an intake air temperature sensor for detecting a temperature of intake air, a supply controller for actuating the secondary air supplying device in accordance with a predetermined secondary air supply condition, and a summing unit for summing an actuation period of the secondary air supplying device and storing a sum. The supply controller stops the secondary air supply by the secondary air supplying device when the sum stored by the summing unit reaches a predetermined upper limit.

Abstract: Injection of secondary air (AI) into an exhaust gas pipe upstream of an exhaust gas purification catalyst is performed after a startup of an engine, in order to accelerate the warm-up of the catalyst. If the degree of catalyst warm-up during the AI is greater than or equal to a predetermined criterion degree of the warm-up and the engine output is greater than or equal to a criterion output, the injection of secondary air is stopped and exhaust gas purification on the catalyst is conducted so as to curb degradation of emissions.

Abstract: An anomaly judgment apparatus for a secondary air supply system which includes a secondary air supply path for introducing secondary air into an exhaust path of an internal combustion engine and an open-close valve disposed in the secondary air supply path. The valve is opened and/or closed by drive force of negative pressure introduced from a portion of an intake path of the engine downstream of a throttle valve. The anomaly judgment apparatus includes an anomaly judgment section for judging whether or not the secondary air supply system is anomalous; a negative pressure judgment section for judging whether or not the negative pressure is secured to a degree required for the drive force to reliably open and/or close the open-close valve; and an anomaly judgment prohibition section for prohibiting judgment by the anomaly judgment section when the negative pressure is not secured to the required degree.

Abstract: An anomaly judgment apparatus for a secondary air supply system which includes a secondary air supply path for introducing secondary air from an intake path of an engine into an exhaust path at a location upstream of a catalytic converter disposed in the exhaust path. The apparatus includes a pressure detector for detecting pressure in the secondary air supply path, and an anomaly judgment section for calculating pulsation level indicative of the degree of pulsation of pressure detected by the pressure detector and for judging, on the basis of at least the pulsation level, whether or not the secondary air supply system is anomalous. The apparatus further includes an anomaly judgment prohibiting section for prohibiting judgment by the anomaly judgment section when the degree of propagation of intake air pulsation arising in the intake path into the secondary air supply path is equal to or higher than a predetermined level.

Abstract: A failure diagnosis apparatus for secondary air supplier according to the present invention determines a failure of a secondary air supplier based on pressure and pressure pulsation in a secondary air supply path. A failure diagnosis is made by determining the presence or absence of pressure pulsation in the secondary air supply path based on a determination threshold, and in the present invention the determination threshold is varied according to a pressure value in the secondary air supply path (a smoothed value or an average value of measured pressure). This permits the apparatus to make an accurate failure diagnosis, while eliminating pressure pulsations except for that due to exhaust pulsation (e.g., that due to noise of the pressure sensor and that caused by surging of an air pump).

Abstract: A secondary air supply system includes an exhaust gas control catalyst which is provided in an exhaust system in an internal combustion engine, and which purifies a harmful component in exhaust gas; a secondary air supply device which supplies secondary air into the exhaust gas upstream of the exhaust gas control catalyst; a secondary air supply stop device which stops the secondary air supply performed by the secondary air supply device; a fuel supply device which supplies fuel to the internal combustion engine; a fuel amount increasing device which increases a fuel amount supplied to the internal combustion engine during the secondary air supply; and a fuel amount increase stop time delaying device which delays, by a predetermined delay period, a stop time at which the increase in the fuel amount caused by the fuel amount increasing device is stopped even when the secondary air supply is stopped.

Abstract: An internal combustion engine includes an air pump that supplies secondary air to an upstream side of an exhaust gas control catalyst in an exhaust pipe via a secondary air supply passage; an adjusting device that adjusts an intake air amount delivered into a combustion chamber from an intake pipe; and a controller that performs control for increase correction of the intake air amount adjusted by the adjusting device when the air pump performs an operation of supplying the secondary air. Thus, it is possible to prevent a problem caused by a reduction in an engine speed due to the secondary air supply.

Abstract: Injection of secondary air (AI) into an exhaust gas pipe upstream of an exhaust gas purification catalyst is performed after a startup of an engine, in order to accelerate the warm-up of the catalyst. If the degree of catalyst warm-up during the AI is greater than or equal to a predetermined criterion degree of the warm-up and the engine output is greater than or equal to a criterion output, the injection of secondary air is stopped and exhaust gas purification on the catalyst is conducted so as to curb degradation of emissions.

Abstract: The invention relates to a secondary air feeding apparatus and a method of detecting an abnormality in the apparatus capable of making a precise determination on abnormalities in components and detecting operational failures as well. According to one aspect of the invention, the opening-closing state of opening-closing means (ASV) is switched during the operation of an air pump, and abnormalities in respective components are detected on the basis of pressure values and pressure fluctuation values detected by a pressure sensor disposed between the air pump and the ASV before and after the switching of the opening-closing means.

Abstract: When the determination result of failure determination at a start of AI (auxiliary air injection=supply) is that there is a possibility of a closing anomaly due to freezing, a reevaluation process 1 being a reevaluation after a warm-up is performed. When the determination result of determination at an end of AI is that there is a possibility of an opening anomaly due to freezing, a reevaluation process 2 being a reevaluation after a warm-up is performed.

Abstract: A secondary air supply apparatus controls emissions from an engine through secondary combustion of combustible matters in exhaust gas accomplished by supplying air to an exhaust pipe upstream of an emission control device. A pressure behavior pattern is determined from a pressure value detected by a pressure sensor disposed between an air pump and an open-close valve, and a pressure variation value. The secondary air supply apparatus determines operational states of the air pump and the open-close valve based on variations of the pressure behavior pattern at the time of a secondary air supply control and at the time of a secondary air stop control.

Abstract: The idling speed controller for an internal-combustion engine includes a judging device for determining whether the internal-combustion engine is in an idling state and whether a variation in the revolutional speed of the internal-combustion engine is equal to or greater than a predetermined value, an air amount adjuster that adjusts an air amount supplied to the internal-combustion engine when it is determined that the internal-combustion engine is in the idling state and the variation in the revolutional speed of the internal-combustion engine is equal to or greater than the predetermined value; and a device for prohibiting the adjustment of the air amount by the air amount adjuster after the passing of a predetermined time from a change of a throttle valve form an open state to a substantially closed state.