Mitsubishi Jidosha Kogyo Kabushiki Kaisha

Mitsubishi Denki Kabushiki Kaisha

Takanao Yokoyama

Masato Yoshida

Katsuhiko Miyamoto

Kazumasa Iida

Muneyoshi Nanba

Yoshihiko Kato

Toshio Iwata

Atsushi Ueda

Tooru Okada

In a fuel blending ratio detecting method, a first blending ratio of the methanol in the fuel supplied to an internal combustion engine is detected by a blending ratio sensor; an air/fuel ratio feedback compensation coefficient computed on the basis of an output of an O.sub.2 sensor is used to compute a feedback learned value, and the current blending ratio compensation coefficient is multiplied by this value to compute the next blending ratio compensation coefficient so as to obtain a second blending ratio; the current blending ratio compensation coefficient is multiplied by a peak mean value of the computed feedback compensation coefficient to compute the next blending ratio compensation coefficient so as to obtain a third blending ratio; and the first, second or third blending ratio is selected according to the operating conditions of the internal combustion engine. Thus, the selected blending ratio is always used as the control blending ratio very close to the true ratio, so that the internal combustion engine can be accurately controlled.

Method for detecting fuel blending ratio

A method includes a step of calculating an estimated blending ratio of a mixed fuel supplied to a combustion chamber of an internal combustion engine and a following equation is effected in this step to derive the estimated blending ratio:

Method for detecting blending ratio of mixed fuel to be supplied to

An air-fuel ratio feedback control method for a multi-fuel internal combustion engine using a dual O.sub.2 sensor system is provided, in which the concentration of oxygen in exhaust gas on the upstream side of an exhaust gas purifier is detected, a value corresponding to the detected oxygen concentration is compared with a first target value, and the air-fuel ratio is feedback-controlled in accordance with the result of the comparison. The mixture ratio of at least two fuels is detected, and a second target value is set in accordance with the detected fuel mixture ratio. On the other hand, the concentration of oxygen in the exhaust gas on the downstream side of the exhaust gas purifier is detected, and a value corresponding to the detected downstream-side oxygen concentration is obtained. The first target value is corrected in accordance with the difference between the obtained value and the second target value.

Air-fuel ratio feedback control method for a multi-fuel internal

Provided according to the present invention is a vehicular engine cooling apparatus comprising cooling fan means for cooling at least one of an engine and an environment of the engine, the engine being operated with use of any of two or more different fuels and a mixed fuel formed of a combination of the different fuels. This apparatus further comprises a mixture ratio sensor for detecting the mixture ratio of the two or more different fuels, and a controller for actuating the cooling fan means in accordance with the fuel mixture ratio detected by the mixture ratio sensor, after the engine is stopped. Preferably, the cooling fan is operated only during a predetermined operating time set in accordance with the fuel mixture ratio and the temperature of at least one of the engine and the environment of the engine.

Vehicular engine cooling apparatus

In an engine using fuel mixture of gasoline and methanol, the present control system compensates a detection value of a blend ratio sensor with a detection value of a knock sensor, or causes trouble detecting means to detect a failure of the blend ratio sensor and memories the blend ratio immediately before the failure as an assumed blend ratio and compensates the stored value with the detection value of the knock sensor, whereby the engine control is executed based on the control blend ratio and the ignition timing acquired through the compensation.

Engine control system

A control apparatus for an internal combustion engine operable on fuels of different octane numbers implements automatic control when the engine knocks to correct the ignition timing preset in accordance with the octane number of the fuel in use to the retarded side so that the engine operates under the optimum condition. This automatic control enhances engine output and drivability, prevents engine fracture and saves fuel cost.

Growing community of inventors

Nagaokakyo, Japan

Takanao Yokoyama