Mazda Motor Corporation

Toyo Kogyo Co., Ltd.

Katsumi Okazaki

Yasuhiro Yuzuriha

Mitsuo Hitomi

Kiyotaka Mamiya

Tadataka Nakazumi

Junso Sasaki

Hiroyuki Oda

Tomomi Watanabe

Katsuhiko Yokooku

Noboru Hashimoto

Masanori Misumi

Akinori Yamashita

Akihito Nagao

Tsugio Fukube

Toshiyuki Terashita

Yoshinori Honiden

A combustion chamber structure including a cylinder head having a bottom surface for defining an upper portion of a combustion chamber, a piston having a top surface for defining a lower portion of the combustion chamber, an intake recess formed in the cylinder head for an intake port of the combustion chamber to define a part the chamber, an exhaust recess formed in the cylinder head for an exhaust port to define a part of the chamber. The intake recess is smaller than the exhaust recess in volume. An extended wall portion is formed at a boundary portion between the intake and exhaust recess in the cylinder head to extend along the intake port and project into the exhaust recess. An ignition plug is arranged in the vicinity of a tip end of the extended wall portion. A compact structure of the combustion chamber can be obtained with an improved combustion property.

Combustion chamber of internal combustion engine

An intake system with a simple and compact structure for an internal combustion engine having a plurality of cylinders each cylinder having an intake port, the opening timing of the intake ports being determined so that that of each cylinder overlaps with that of another in which the intake stroke takes place subsequently to that in the former, the intake system comprising intake passges each being connected to the intake port of one of the cylinders, a juction portion connected to the respective intake passages, a resonance intake passage connected to the junction portion at one end thereof, in which the intake pressure resonance effect is to be produced and control valves provided in the respective intake passages, the opening timing of the respective control valves being determined so as to be retarded relative to that of said respective intake ports under at least a low speed and heavy load engine operating condition.

Intake system for internal combustion engines

An intake system for a multiple-cylinder engine has a main intake passage open to the atmosphere at its upstream end, a plurality of discrete intake passages which communicate the respective cylinders with the main intake passage by way of intake ports, and a circular passage which is communicated with the cylinders. The circular passage is adapted to propagate pressure waves generated by the intake strokes without reflecting the pressure waves, and is provided with a valve which opens the circular passage to permit propagation of the pressure waves in a predetermined high engine speed range. The length of the circular passage is selected so that the pressure waves resonate in the predetermined high engine speed range.

Intake system for multiple-cylinder engine

An air-fuel ratio control system for an engine in which a fuel injection amount is calculated according to the engine operating conditions and is corrected according to the output of an air-fuel ratio sensor, comprises a base fuel injection amount calculating section for calculating a base fuel injection amount corresponding to the stoichiometric air-fuel ratio on the basis of the intake air amount, a target air-fuel ratio calculating section for calculating a target air-fuel ratio according to the engine operating condition, a reference value calculating section for calculating a reference value which represents the target air-fuel ratio and is submitted to comparison with the output of the air-fuel ratio sensor, a feedback correction coefficient calculating section for calculating a feedback coefficient according to the deviation of the output of the air-fuel ratio sensor from the reference value, and a final fuel injection amount calculating section which corrects the base fuel-injection amount on the basis of the ratio of the stoichiometric air-fuel ratio to the target air-fuel ratio and the feedback coefficient to obtain a final fuel injection amount.

Air-fuel ratio control system for engine

An intake system for an internal combustion engine comprises a first valve provided to open and close an intake passage leading to each combustion chamber, a bypass passage for introducing intake air into each combustion chamber bypassing the first valve, and a second valve provided to open and close each of the bypass passages. The first valves are operated to close the respective intake passages in a light load range and to open the same in a heavy load range. The second valve is operated to close the bypass passage in the middle of each intake stroke. The first valves are controlled so that the opening of the intake passages is increased as the engine load increases after exceeding a predetermined value, and the second valve is controlled to delay the time the bypass passage is closed with increase in the engine load so that the time the bypass passage is opened overlaps with the time the intake valve is opened when the engine load reaches the predetermined value.

Intake system for internal combustion engine

An air-to-fuel ratio control system for an internal combustion engine comprises means for performing a feedback control for keeping a fuel mixture to have the theoretical air-to-fuel ratio or approximations thereof in response to the output of an air-to-fuel ratio sensor, means for conducting the learning to compute a supplemental feedback quantity of fuel used for revising the quantity of fuel by which the fuel actually supplied is determined in at least one of partitions of the operating condition of the engine under the feedback control, means for memorizing the supplemental feedback quantity of fuel in at least one of memorizing areas partitioned in accordance with the partitions of the operating condition of the engine as a resultant of the learning, means for renewing the resultant of the learning in each of the remaining memorizing areas on the strength of the resultant of the learning newly memorized in at least one of memorizing areas, and means for supplying the fuel of the quantity computed with the renewed resultant of the learning in each memorizing area so as to produce the fuel mixture having a desired air-to-fuel ratio different from the theoretical air-to-fuel ratio and approximations thereof through an open-loop control under the situations where the operation of the engine meets predetermined conditions.

Air-to-fuel ratio control systems for internal combustion engines

An ignition timing control system for an automobile internal combustion engine comprises knocking detecting circuitry, ignition timing control circuitry and inhibiting circuitry. The inhibiting circuitry is operable to interrupt the supply of an output signal from the detecting circuitry to the control circuitry only when the engine, which has been operated under a particular operating condition wherein the engine speed is lower than a predetermined speed value while the actual load imposed on the engine is larger than a predetermined load value, is operated under any one of operating conditions other than such particular operating conditions.

Growing community of inventors

Hiroshima, Japan

Katsumi Okazaki