There is provided an ignition apparatus that makes it possible that after a spark discharge starts, a secondary current is reduced so that a plug is suppressed from being consumed. The ignition apparatus is provided with an ignition coil including a primary coil, a secondary coil, and a tertiary coil, a first switching circuit for performing on/off-switching of energization of the primary coil from a power source, a second switching circuit for performing on/off-switching of energization of the tertiary coil, and a controller that performs on/off-control of the first switching circuit so as to generate a secondary current in the secondary coil, thereby causing a spark discharge in an ignition plug, and then turns on the second switching circuit so as to reduce the secondary current through a change in flux in the tertiary coil.

An igniter includes a switch element with input, output control electrodes, a first lead in contact with the input electrode and connected to a primary coil of an ignition coil, a second lead that is grounded, a third lead spaced apart from the first and second leads, a first bonding wire connecting the output electrode and the third lead, a second bonding wire connecting the third lead and the second lead, and a control IC that drives the switch element based on an ignition instruction signal from an engine control unit. The control IC generates an ignition confirmation signal based on the voltage of the third lead, and outputs the signal to the engine control unit.

An ignition device for an internal combustion engine includes an ignition coil, a first switch, a secondary current adjuster, and controller. The ignition coil includes a primary coil, a core, and a secondary coil. The first switch switches an energized state of the primary coil between an ON state and an OFF state. The secondary current adjuster adjusts a current value of a secondary current flowing through the secondary coil. The controller controls the secondary current adjuster so that a current value of the secondary current in at least a part of a charging period of the ignition plug, which is a period from when the energized state of the primary coil is switched from the ON state to the OFF state by the first switch to when dielectric breakdown occurs in the ignition plug, becomes smaller than a peak value of the secondary current after the dielectric breakdown occurs.

The invention relates to an improved ignition system for spark ignited combustion engines. According to the invention the voltage over a coil winding 6P on the primary side of the ignition coil is regulated to a sufficiently low voltage level during timed periods of the ignition cycle, such that at least one function out of three in total, i.e. prevention of premature spark-on-make, or spark suppression after onset of ignition, or improved frequency response between primary and secondary side of the ignition coil after end of ignition, is obtained. When applied in an inductive ignition system a differential amplifier (8) may be connected over the primary winding 6P regulating a control switch 2CS via a drive unit (9). The invention is preferably implemented in ignition systems with ion sense circuitry 5C,5R on the secondary side of the ignition coil, and implementing all three functions.

An ignition control system for an internal combustion engine includes a controller, which includes an IGT generating section and an IGW generating section and is connected to ignition devices through an IGT signal line and an IGW signal line. The IGW signal line includes bifurcated portions, which sequentially bifurcate from a common main signal line. The bifurcated portions each correspond to one of the ignition devices and include a branched line, which is connected to an energy supply circuit inside the corresponding ignition device.

An ignition device for an internal combustion engine includes an ignition coil, a first switch, a secondary current adjuster, and controller The ignition coil includes a primary coil, a core, and a secondary coil. The first switch switches an energized state of the primary coil between an ON state and an OFF state. The secondary current adjuster adjusts a current value of a secondary current flowing through the secondary coil. The controller controls the secondary current adjuster so that a current value of the secondary current in at least a part of a charging period of the ignition plug, which is a period from when the energized state of the primary coil is switched from the ON state to the OFF state by the first switch to when dielectric breakdown occurs in the ignition plug, becomes smaller than a peak value of the secondary current after the dielectric breakdown occurs.

An igniter controls a current flowing in a coil unit for supplying a high voltage to a spark plug for use in an internal combustion engine. The igniter includes: a pyrogenic power element, a metal block, a lead frame, and a controller. The lead frame electrically connects the metal block and the coil unit to each other. The controller controls the operation of the power element. The power element is fixed directly to the metal block by soldering at a surface of the power element on one side, and is electrically connected to the controller at a surface of the power element on the other side. With this configuration, heat generated during the operation of the power element is transferred smoothly in a moment to the metal block. As a result, temperature increase at the power element is suppressed during the operation of the power element.

An ignition control system for an internal combustion engine includes a controller, which includes an IGT generating section and an IGW generating section and is connected to ignition devices through an IGT signal line and an IGW signal line. The IGW signal line includes bifurcated portions, which sequentially bifurcate from a common main signal line. The bifurcated portions each correspond to one of the ignition devices and include a branched line, which is connected to an energy supply circuit inside the corresponding ignition device.

An ignition device includes: a primary coil including a first winding and a second winding connected in series to the first winding; a secondary coil connected to a spark plug and magnetically coupled to the primary coil; a first switch that opens or closes the electrical path between the first terminal and the ground; a second switch that opens or closes the electrical path between the power source and the second terminal; a third switch that opens or closes the electrical path between the power source and the connection point; a fourth switch that opens or closes the electrical path between the second terminal and the ground; and a switch control unit that controls the opening and closing of each switch to open or close each electrical path.

The subject matter of this specification can be embodied in, among other things, a method that includes receiving a collection of measurements of electric current amplitude in a primary winding of an engine ignition system having the primary winding and a spark plug, identifying an ignition start time, identifying an inflection point based on the plurality of measurements, determining an inflection point time representative of a time at which the identified inflection point occurred, determining a spark start time based on an amount of time between the ignition start time and the inflection point time, and providing a signal indicative of the spark start time.