Abstract: An intake system for an internal combustion engine comprises an intake pipe structure connected through an intake manifold to cylinders of the engine, a fuel injection valve for injecting fuel into the intake pipe structure to form an air-fuel mixture, a throttle valve disposed in the intake pipe structure, and a baffle plate disposed in the intake pipe structure between the fuel injection valve and the throttle valve for promoting fuel atomization. The baffle plate has a surface which faces the fuel injection valve with a predetermined distance from the latter in order that the fuel injected from the fuel injection valve may impinge on the surface, and an outer edge spaced from an inner wall surface of the intake pipe structure to define a mixture passage therebetween.

Abstract: A method for controlling the ignition timing of internal combustion engines in which the magnitude of knocking is detected for each of at least two different magnitude levels. A knocking signal representing the detected magnitude level of the knocking and produced in each combustion cycle of the engine is sampled for a predetermined number of combustion cycles of the engine, and an ignition timing correction signal is produced to effect either to retard or advance depending on whether the sampled number of the knocking signals is above or below a predetermined reference number.

Abstract: An ignition timing control system for internal combustion engines includes a knock detecting circuit for determining the presence or absence of the knocking in response to a signal from a knock detector, and includes a correction advance computing circuit for computing a correction value of ignition advance thereby to retard the ignition timing by a predetermined angle when the knock is present and to advance the ignition timing when the knock is absent. A further battery is provided to supply electric power to the correction advance computing circuit even after a key switch associated with a main battery for supplying power to the ignition timing control system has been turned off. Hence, the correction advance computing circuit memorizes the computed advance correction value corresponding to a knock condition of the engine just prior to the turn-off of the key switch and the memorized advance correction value is made available in a subsequent operation of the ignition timing control system.

Abstract: An ignition timing control system including a counter into which is introduced a data generated from a memory and indicative of the proper ignition advance corresponding to the operating conditions of an engine and the decrement or increment of the count is made in synchronism with predetermined degrees of rotation of the engine to determine the desired ignition timing. When knock occurs n times per m times of engine explosion stroke, the knocking ratio n/m is computed and the content of the counter is corrected in response to the value of the knocking ratio to correct the ignition timing. The value of m for the knocking ratio n/m is variable in accordance with the engine operating conditions.

Abstract: A method of and apparatus for controlling ignition timing of an internal-combustion engine in accordance with the degree of knocking, the apparatus comprising a knock detector for detecting a vibration corresponding to knocking of the internal-combustion engine, a knock detector circuit responsive to output from the knock detector for detecting the knocking of the internal-combustion engine, and corrective advance computing circuit responsive to an output signal from the knock detector circuit for controlling ignition timing of the engine, wherein the corrective advance computing circuit counts the number of knocks detected during a period of predetermined combustion cycles, compares the number of knocks with a predetermined number, and controls ignition to advance or delay it in accordance with the result of comparison.