Nippondenso Co., Ltd.

Ko Narita

Hiroshi Haraguchi

Toshiharu Iwata

Koichi Toyama

Toshihito Nonaka

Takeshi Matsui

An ignition system for and internal combustion engine ignition coil energization time is controlled in accordance with operating conditions. First and second sections with respective constant angles in an ignition cycle are defined. An integrating circuit integrates in one direction in the second section of a preceding ignition cycle of the angle signal, and in the other direction in the first section of the next ignition cycle. When the integration value reaches a first predetermined value, an energization start signal is generated. An ignition coil begins to be energized at the time of generation of the energization start signal or at the shift of the angle signal from the first section to the second section, whichever arrives earlier, and the energization is stopped when the angle signal shifts from the second to first section. The engine speed is detected to change the rate of integration of the integrating circuit thereby to change the first predetermined value for generating the energization start signal. When the integration value in the second section reaches a second predetermined value cooresponding to the low-speed engine operation, the energization start signal is invalidated thereby to fix the coil energization time in the second section.

Ignition system for internal combustion engine

A current flowing time period control system for an ignition coil of an internal combustion engine is disclosed in which a current flowing time period setting circuit sets the time period for supplying the primary current of the ignition coil and an output signal of the current flowing time period setting circuit is amplified by a drive circuit and supplied to a power transistor, whereby the primary current of the ignition coil is intermittented to control the ignition operation. The current flowing time period control system has a primary current rise detection circuit for detecting the rise period of the primary current of the ignition coil to 1/n of the desired interruption current value (n&gt;1), and includes an accumulation device in which the accumulated amount changes gradually in one direction at a first rate until detection of the rise of the ignition coil primary current to 1/n of the desired interruption current value by the rise detection circuit, in the other direction at a second rate gradually at an ignition timing, and again in the original direction at a third rate 1/n of the first rate. In accordance with the accumulated amount of the accumulation device, a time length n times longer than the time period required for the rise of the ignition coil primary current to 1/n of the desired interruption current value is set as a primary current flowing time period for the next ignition cycle.

Current flowing time period control system for ignition coil of internal

An ignition system for internal combustion engines is constructed so that, in response to each ignition signal from ignition signal generating means, through a predetermined angle before a succeeding ignition timing, a storage quantity of storing means is gradually increased from an initial value and then it is gradually decreased, and a time point when the storage quantity of the storing means has been decreased to reach the initial value is detected by first storage quantity detecting means to thereby turn on a power transistor for turning on and off a primary current of an ignition coil at that time point, and further the fact that the storage quantity of the storing means has been decreased to reach a set value larger than the initial value is detected by second storage quantity detecting means to thereby change a decrease rate of the storage quantity of the storing means.

Ignition system for internal combustion engines

In a system for retarding an ignition timing of the engine depending on a signal from a knock detector, the knocking intensity and the knocking frequency are discriminated in accordance with the signal of the knock detector. On the basis of the discriminated results, the system provides a small amount of retard angle for ignition timing per one knocking when the knocking frequency is low, that is, the interval between knocking signals is long and the intensity of knocking is light. On the contrary, the system provides a large amount of retard angle when the interval is short and the intensity is heavy.

Ignition timing control system for internal combustion engines

An internal combustion engine ignition timing control system with knock control detects the knocking in an engine and the acceleration of the engine speed to control the ignition timing of the engine. The ignition timing of the engine is retarded in response to the detection of knocking in the engine and the amount of retard is increased as compared with the amount of retard provided under the steady-state condition when the knocking occurs during the acceleration operation of the engine and the frequency of occurrence of knocking is high.

Ignition timing control system with knock control for internal

In an ignition timing control system, a knocking detector detects a knocking of the internal combustion engine. The ignition timing control circuit includes a cylinder switching signal generator circuit for generating a cylinder switching signal in synchronism with the rotation of the engine, a plurality of integrators each corresponding to each or a plurality of cylinders for producing a reference signal in response to the noise signal produced from the knocking detector, a plurality of analog switches for changing one of the integrators into ON-state in response to the cylinder switch signal, and a comparator having an input terminal supplied with the detection signal of the knocking detector and the other input terminal supplied with an integration output signal of the integrators, said comparator producing a knocking signal which retards the ignition timing of the engine when the detection signal is larger in amplitude than the integration signal.

In ignition timing control system for an internal combustion engine, a knocking detector is provided to detect knockings of the engine, and a control unit responsive to the knocking signals of the knocking detector to provide a variable retard amount signal per one knocking which depends on whether the occurrence of another knocking is decided before the lapse of a predetermined time interval from the decision of the knocking.

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Aichi, Japan

Ko Narita