Abstract: An oil retaining amount determination device includes a collected-liquid tank, an element, a thermistor, and a control unit. The collected-liquid tank is arranged in a supply line of CNG. The element separates oil from the CNG that flows into the collected-liquid tank. The thermistor is arranged in a downward direction from the element in the collected-liquid tank and generates heat by being electrified. The control unit determines whether the thermistor is immersed in the oil based on change of a thermistor voltage at the time of electrification of the thermistor. The control unit performs the determination procedure when flow of the CNG in the supply line is stopped.

Abstract: In the present invention, in a control system for a spark ignition internal combustion engine, when a catalyst is not sufficiently active, the ignition timing is advanced to be earlier than MBT to decrease the quantity of hydrocarbons (HC) discharged from the internal combustion engine, and oxygen is supplied to the exhaust gas upstream of the catalyst to thereby oxidize carbon monoxide (CO) discharged from the internal combustion engine. According to this invention, exhaust emissions emitted before activation of the exhaust gas purification apparatus can be decreased as much as possible, and early activation of the catalyst can be achieved by making use of heat generated by oxidation reaction of carbon monoxide (CO).

Abstract: A present exhaust purifying apparatus comprises a SCR catalyst, a urea-water injector, and a downstream air-fuel ratio sensor (an oxygen concentration sensor having a diffusion resistance layer) disposed at a position downstream of the SCR catalyst. The present apparatus, when a predetermined condition is satisfied, stops injecting the urea-water from the urea-water injector, and obtains an output value of the downstream air-fuel ratio sensor, as a first output value, in that state. The present apparatus obtains an output value of the downstream air-fuel ratio sensor when the urea-water is being injected from the urea-water injector, as a second output value. The present apparatus obtains a concentration of ammonia which flows out from the SCR catalyst based on the difference between the first output value and the second output value.

Abstract: An ignition control system for a spark ignition internal combustion engine has: over-advancing means for over-advancing an ignition time for a cylinder of the internal combustion engine beyond an MBT; obtaining means for obtaining an adhering fuel amount that is the amount of fuel that adheres to the inner face of the cylinder of the internal combustion engine; and controlling means for controlling the over-advancing means to execute the ignition time over-advancement when the adhering fuel amount obtained by the obtaining means is equal to or larger than a predetermined amount.

Abstract: An output calibration apparatus for an NOx sensor according to the present invention includes a urea addition valve provided in an exhaust passage in an internal combustion engine to allow urea to be added to inside of the exhaust passage, and an NOx sensor provided at least downstream of the urea addition valve, the NOx sensor being capable of detecting not only an NOx concentration but also an ammonia concentration. The output calibration apparatus executes fuel cut on the internal combustion engine, and calibrates a gain of the NOx sensor based on ammonia obtained from the urea added via the urea addition valve during execution of the fuel cut. The ammonia obtained from the urea added during execution of the fuel cut is used as standard gas to calibrate the gain of the NOx sensor.

Abstract: A device for controlling an internal combustion engine which uses, as the fuel, a heavy fuel, a light fuel, an alcohol fuel and a mixture thereof, comprising a heavy fuel/light fuel ratio detector 39 capable of detecting the ratio of the heavy fuel and the light fuel, and an air-fuel ratio detector 41 for detecting the air-fuel ratio of the exhaust gas, wherein the amount of fuel injection is calculated based on the heavy fuel/light fuel ratio detector so that the air-fuel ratio becomes a target air-fuel ratio. The heavy fuel/light fuel ratio detector is diagnosed if it is in an abnormal condition based on a difference between the target air-fuel ratio and the air-fuel ratio detected by the air-fuel ratio detector while the engine temperature is in a particular temperature region. The heavy fuel/light fuel ratio detector can be correctly diagnosed if it is in an abnormal condition even when an alcohol-mixed fuel is used.

Abstract: An output calibration apparatus for an NOx sensor according to the present invention includes a urea addition valve provided in an exhaust passage in an internal combustion engine to allow urea to be added to inside of the exhaust passage, and an NOx sensor provided at least downstream of the urea addition valve, the NOx sensor being capable of detecting not only an NOx concentration but also an ammonia concentration. The output calibration apparatus executes fuel cut on the internal combustion engine, and calibrates a gain of the NOx sensor based on ammonia obtained from the urea added via the urea addition valve during execution of the fuel cut. The ammonia obtained from the urea added during execution of the fuel cut is used as standard gas to calibrate the gain of the NOx sensor.

Abstract: A present exhaust purifying apparatus comprises a SCR catalyst, a urea-water injector, and a downstream air-fuel ratio sensor (an oxygen concentration sensor having a diffusion resistance layer) disposed at a position downstream of the SCR catalyst. The present apparatus, when a predetermined condition is satisfied, stops injecting the urea-water from the urea-water injector, and obtains an output value of the downstream air-fuel ratio sensor, as a first output value, in that state. The present apparatus obtains an output value of the downstream air-fuel ratio sensor when the urea-water is being injected from the urea-water injector, as a second output value. The present apparatus obtains a concentration of ammonia which flows out from the SCR catalyst based on the difference between the first output value and the second output value.

Abstract: An object to be achieved by the present invention is to achieve ignition timing that is suitable for an environment in which a spark ignition internal combustion engine is used during the period of starting of the internal combustion engine and warm-up thereof just after starting. To achieve this object, according to the present invention, in an ignition control system for an internal combustion engine in which, ignition timing is controlled by feedback in such a way that the engine rotation speed becomes equal to a target rotation speed when the temperature of the internal combustion engine is lower than a prescribed temperature, and retard control for retarding the ignition timing by a predetermined amount from target ignition timing is performed when the temperature of the internal combustion engine is equal to or higher than the prescribed temperature, the aforementioned prescribed temperature is changed according to the altitude of the place where the internal combustion engine is used.

Abstract: In at least a first cycle at startup, an opening timing of an exhaust valve is controlled to 45 degrees before-bottom-dead-center of an exhaust stroke, or to a retard side of the normal closing timing that is set after warm-up is complete. Also, the closing timing of the exhaust valve is preferably controlled to an advance side of top-dead-center in a second cycle at startup and thereafter at the latest. Accordingly, the amount of unburned HC discharged during a cold start of an internal combustion engine is reduced.

Abstract: When starting an internal combustion engine from cold, after-burning of unburned HC in the exhaust gas within an exhaust passage is promoted by supplying secondary air into the exhaust passage upstream of a catalyst. At this time, the pressure within the exhaust passage is controlled by controlling the opening timing of an exhaust valve. Desirably, when the exhaust temperature has been elevated to a temperature at which it is possible to promote after-burning of the unburned HC in the exhaust gas within the exhaust passage, the opening timing of the exhaust valve is retarded.

Abstract: In the present invention, in a control system for a spark ignition internal combustion engine, when a catalyst is not sufficiently active, the ignition timing is advanced to be earlier than MBT to decrease the quantity of hydrocarbons (HC) discharged from the internal combustion engine, and oxygen is supplied to the exhaust gas upstream of the catalyst to thereby oxidize carbon monoxide (CO) discharged from the internal combustion engine. According to this invention, exhaust emissions emitted before activation of the exhaust gas purification apparatus can be decreased as much as possible, and early activation of the catalyst can be achieved by making use of heat generated by oxidation reaction of carbon monoxide (CO).

Abstract: An ignition control system for a spark ignition internal combustion engine has: over-advancing means for over-advancing an ignition time for a cylinder of the internal combustion engine beyond an MBT; obtaining means for obtaining an adhering fuel amount that is the amount of fuel that adheres to the inner face of the cylinder of the internal combustion engine; and controlling means for controlling the over-advancing means to execute the ignition time over-advancement when the adhering fuel amount obtained by the obtaining means is equal to or larger than a predetermined amount.

Abstract: An object to be achieved by the present invention is to achieve ignition timing that is suitable for an environment in which a spark ignition internal combustion engine is used during the period of starting of the internal combustion engine and warm-up thereof just after starting. To achieve this object, according to the present invention, in an ignition control system for an internal combustion engine in which, ignition timing is controlled by feedback in such a way that the engine rotation speed becomes equal to a target rotation speed when the temperature of the internal combustion engine is lower than a prescribed temperature, and retard control for retarding the ignition timing by a predetermined amount from target ignition timing is performed when the temperature of the internal combustion engine is equal to or higher than the prescribed temperature, the aforementioned prescribed temperature is changed according to the altitude of the place where the internal combustion engine is used.

Abstract: A device for controlling an internal combustion engine which uses, as the fuel, a heavy fuel, a light fuel, an alcohol fuel and a mixture thereof, comprising a heavy fuel/light fuel ratio detector 39 capable of detecting the ratio of the heavy fuel and the light fuel, and an air-fuel ratio detector 41 for detecting the air-fuel ratio of the exhaust gas, wherein the amount of fuel injection is calculated based on the heavy fuel/light fuel ratio detector so that the air-fuel ratio becomes a target air-fuel ratio. The heavy fuel/light fuel ratio detector is diagnosed if it is in an abnormal condition based on a difference between the target air-fuel ratio and the air-fuel ratio detected by the air-fuel ratio detector while the engine temperature is in a particular temperature region. The heavy fuel/light fuel ratio detector can be correctly diagnosed if it is in an abnormal condition even when an alcohol-mixed fuel is used.

Abstract: In at least a first cycle at startup, an opening timing of an exhaust valve is controlled to 45 degrees before-bottom-dead-center of an exhaust stroke, or to a retard side of the normal closing timing that is set after warm-up is complete. Also, the closing timing of the exhaust valve is preferably controlled to an advance side of top-dead-center in a second cycle at startup and thereafter at the latest. Accordingly, the amount of unburned HC discharged during a cold start of an internal combustion engine is reduced.

Abstract: An intake port of an internal combustion engine 10 is provided with a fuel injection valve 22. An intake adjustment mechanism 30 for varying the valve timing of an intake valve 24 and an exhaust adjustment mechanism 32 for varying the valve timing of an exhaust valve 26 are furnished. Immediately after internal combustion engine startup, fuel atomization is facilitated by exercising control so that the valve opening timing for the intake valve 24 coincides with a retarded valve opening timing after exhaust top dead center. In such an instance, the fuel introduced into a cylinder is inhibited from adhering to the exhaust valve 26 and its neighborhood by exercising control in such a manner that the valve closing timing for the exhaust valve 26 coincides with a retarded vale closing timing, which is retarded from a normal valve closing timing.

Abstract: In an ignition control system for an internal combustion engine which is capable of advancing the ignition timing beyond the MBT, the amount of fuel used for the combustion in a cylinder is made appropriate by performing a decreasing correction of the amount of fuel injection of a fuel injection valve when the ignition timing is advanced beyond the MBT.

Abstract: Provided is a control apparatus and a control method of an internal combustion engine which can intend to suppress a deterioration of an emission and suppress a reduction of a startability. According to the method, a target ignition timing at a time of starting an internal combustion engine is acquired (step ST101); an ignition timing is controlled to a spark advance side and an air fuel ratio of the internal combustion engine is controlled to a lean side (step ST103) if a start of a cranking is judged (step ST102); the ignition timing is controlled to a spark retard side (step ST106) if an end of a first cycle after the cranking is judged based on the acquired engine speed (steps ST104 and ST105); and a spark advance correction of the ignition timing to a spark advance direction in correspondence to an exhaust temperature is executed until the ignition timing comes to the target ignition timing (steps ST108, ST109, and ST110).

Abstract: An intake port of an internal combustion engine 10 is provided with a fuel injection valve 22. An intake adjustment mechanism 30 for varying the valve timing of an intake valve 24 and an exhaust adjustment mechanism 32 for varying the valve timing of an exhaust valve 26 are furnished. Immediately after internal combustion engine startup, fuel atomization is facilitated by exercising control so that the valve opening timing for the intake valve 24 coincides with a retarded valve opening timing after exhaust top dead center. In such an instance, the fuel introduced into a cylinder is inhibited from adhering to the exhaust valve 26 and its neighborhood by exercising control in such a manner that the valve closing timing for the exhaust valve 26 coincides with a retarded vale closing timing, which is retarded from a normal valve closing timing.