Toyota Jidosha Kabushiki Kaisha

Nippon Soken, Inc.

Nao Murase

Hiroki Ichinose

Yuuichi Katou

Nobuhiko Koga

Shogo Suda

Masahiro Ozawa

Keiichiro Aoki

Takahiko Fujiwara

Rentaro Kuroki

Rie Osaki

Yuuichi Kato

Yoichiro Goya

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).

Control system for internal combustion engine

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.

Exhaust purifying apparatus for an internal combustion engine

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.

Ignition control system for internal combustion engines

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.

Output calibration apparatus and output calibration method for NOx sensor

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 detectorcapable of detecting the ratio of the heavy fuel and the light fuel, and an air-fuel ratio detectorfor 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.

Device for controlling internal combustion engines

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.

Ignition control system for internal combustion engine

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.

Control apparatus and control method for internal combustion engine

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.

Control device and control method for internal combustion engine

An intake port of an internal combustion engineis provided with a fuel injection valve. An intake adjustment mechanismfor varying the valve timing of an intake valveand an exhaust adjustment mechanismfor varying the valve timing of an exhaust valveare furnished. Immediately after internal combustion engine startup, fuel atomization is facilitated by exercising control so that the valve opening timing for the intake valvecoincides 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 valveand its neighborhood by exercising control in such a manner that the valve closing timing for the exhaust valvecoincides with a retarded vale closing timing, which is retarded from a normal valve closing timing.

Valve timing control device

An ECU executes a determination process determining whether the rate of increase in the engine speed is above a prescribed rate immediately after the engine start, and if so, delays the ignition timing.

Internal combustion engine and ignition control method

In an internal combustion engine including a plurality of cylinders, a fuel injection system and method sets an amount of fuel injected into each cylinder sequentially in a first cycle of fuel injection during a normal engine start in which an engine speed increases, such that an amount of fuel to be injected into one of the cylinders where the last injection is to be performed within the first cycle is larger than an amount of fuel to be injected into another one of the cylinders in the first injection within the first cycle.

Growing community of inventors

Susono, Japan

Nao Murase