Mazda Motor Corporation

Toshihiro Ishihara

Tetsushi Hosokai

Tetsuro Takaba

Hideki Kobayashi

Takahiro Inada

Tsunehisa Okuda

Tomoji Izumi

Satoru Ando

Kazuyoshi Okuda

Kenji Shimizu

Yoshiaki Sugamoto

A vehicle drive control system performs a speed control, in which the vehicle is controlled to travel at a desired cruising speed, and a distance control, in which the vehicle is controlled to keep a safe distance from a vehicle ahead of the vehicle with the drive control. The system is equipped with a feature in which a speed of the preceding vehicle is estimated when a range finder, which monitors a distance from the preceding vehicle, loses sight of the preceding vehicle during the distance control so as to establish a target cruising speed which the subject vehicle ought to attain according to the estimated speed of the preceding vehicle.

Drive control system for automotive vehicle

A traveling control system for a motor vehicle includes a detector for detecting an object which exists in front of the motor vehicle to follow a vehicle traveling ahead. The system further includes a first course determination device for estimating a first course on which the motor vehicle will travel hereafter, an identification device for identifying an first target vehicle among the objects existing on the first course, and a second course estimation device for estimating, based on the first target vehicle, a second course on which the motor vehicle will travel hereafter at least while the first target vehicle is outside of the first course. The identification device identifies a second target vehicle among vehicles which travel on the first or second courses while the first target vehicle is outside of the first course.

Traveling control system for motor vehicle

An ignition timing control system for an engine equipped with an automatic transmission corrects an ignition timing advance so as to retard ignition upon a demand to drop engine output torque when resumption of fuel injection is required after it has been interrupted during deceleration or when a shift of the automatic transmission is required. The ignition timing advance is corrected by a decaying retardation value so as to gradually fall with the passage of time. The corrected ignition timing advance is kept above a specific lower ignition timing advance limit, which is set smaller for lower air charging levels than for higher air charging levels. The corrected ignition timing advance is also kept below a specific lower limit ignition timing advance, which is set larger for lower air charging levels than for higher air charging levels.

Ignition timing control system for engine

A fuel control system for an engine has a fuel injector which injects fuel into an intake passage communicating with a combustion chamber. The quantity of a direct delivery part of fuel injected from the fuel injector which is directly fed to the combustion chamber is estimated, the quantity of a drawn part of fuel which has been on a wall surface of the intake passage and is vaporized and fed to the combustion chamber together with the direct delivery part is estimated, and the quantity of fuel to be injected from the fuel injection means is dcetermined on the basis of the estimated quantities of the direct delivery part and the drawn part so that the sum of them provides a desired quantity of fuel to be fed to the combustion chamber. The estimated quantity of at least one of the direct delivery part and the drawn part is increased as a factor which governs the degree of evaporation of the fuel on the wall surface changes in such a direction as to promote evaporation of the fuel on the wall surface.

Fuel control system for internal combustion engine

An air-fuel ratio control system for an engine has an air-fuel ratio sensor which generates an output value which changes according to an air-fuel ratio in an air-fuel mixture fed to the engine. An upper preset value which corresponds to an output value of the air-fuel ratio sensor for an air-fuel ratio which is larger than a stoichiometric air-fuel ratio and a lower preset value which corresponds to an output value of the air-fuel ratio sensor for an air-fuel ratio which is smaller than the stoichiometric air-fuel ratio are set. They are respectively reduced and increased by a predetermined value at one time at regular intervals, and are shifted each time the output value of the air-fuel ratio sensor exceeds the upper preset value at that time and reduces below the lower preset value at that time, to the output value of the air-fuel ratio sensor at that time. It is determined that the air-fuel ratio sensor is abnormal when the difference between the upper and lower preset values becomes smaller than a predetermined reference difference.

Air-fuel ratio control system for engine

An idle speed control system for an engine includes an idle regulator valve which controls the amount of intake air to be fed to the engine when the engine idles and a control unit which detects an engine speed and controls the opening of the idle regulator valve so that the detected engine speed converges on a target idle speed. The control unit calculates a basic air charging efficienty required to fixedly operate the engine at a target idle speed, calculates a first target air charging efficiency by feedback correction of the basic air charging efficiency on the basis of a correction value which is determined according to the difference between an actual idle speed and a target idle speed, calculates a second target air charging efficiency which is the air charging efficiency obtained when the engine is fixedly operated at a detected idle speed while the amount of intake air is kept at a mass flow which will fixedly provide the first target air charging efficiency, calculates a final target mass flow which provides a first-order lag air charging efficiency equal to the second target air charging efficiency, and controls the opening of the idle regulator valve on the basis of the final target mass flow.

Idle speed control system for engine

An airflow meter detects an amount of intake air flowing through an intake passage of the engine, and a fuel injector injects fuel in an amount which is determined according to the amount of intake air detected by the airflow meter. A controller calculates moving averages of outputs of the airflow meter, and the ratio of the difference between each output of the airflow meter and the moving average to a value derived from the moving average. The controller causes the fuel injector to increase the amount of fuel to be fed to the engine when the ratio is not smaller than a predetermined reference threshold value.

Growing community of inventors

Hiroshima, Japan

Toshihiro Ishihara