A method for checking electrodes of a spark gap of an ignition system for a combustion chamber of an internal combustion engine with an externally provided ignition includes generating a spark at the spark gap in an operating state without ignition of an ignitable mixture in the combustion chamber; ascertaining a parameter or characteristic function representing the spark current, the spark voltage, and/or the spark duration; comparing the parameter or the characteristic function to a reference; adapting an energy for a voltage buildup for a further spark generation for the mixture ignition and/or for maintaining an ignition spark for the mixture ignition, in particular for a future ignition process, as a function of a difference between the parameter or the characteristic function and the reference.

It is possible to adjust electromagnetic energy introduced from a low-voltage side of a primary winding 20 of an ignition coil 2 after start discharging to a spark plug 1 from the ignition coil 2 in the correct proportion by threshold-determining either one or both of a primary voltage V1 applied to a primary side of the ignition coil 2 and a secondary current I2 flowing in a secondary side of the ignition coil 2, and by opening and closing a discharging switch 32 disposed between an auxiliary power supply 3 including an energy storage coil 330 and a low-voltage side terminal 201 of the ignition coil 2.

In a method for creating a spark across a spark gap, in particular for igniting a flammable liquid to measure its flash point, by means of a spark generator which comprises an ignition transformer, wherein the spark generator, on the primary side of the ignition transformer, comprises at least one DC voltage source and, on the secondary side of the ignition transformer, comprises two electrodes delimiting the spark gap to be formed, wherein voltage pulses from the DC voltage source are applied to the ignition transformer on the primary side thereof, which voltage pulses generate ignition voltage pulses on the secondary side, the ignition transformer is operated in a first phase according to the flyback converter principle and in a subsequent, second phase according to the forward converter principle.

Provided is an ignition system including: a main primary coil; a sub primary coil; a secondary coil; a control unit configured to: drive a main IC to switch a main primary coil mode from a de-energization mode to an energization mode; stop the drive of the main IC to switch the main primary coil mode from the energization mode to the de-energization mode; drive the sub IC to switch a sub primary coil mode from a de-energization mode to an energization mode; and stop the drive of the sub IC to switch the sub primary coil mode from the energization mode to the de-energization mode; and a detection circuit configured to detect a state of the secondary coil. The ignition system is configured such that the drive of the sub IC is stopped when the state of the secondary coil detected by the detection circuit is a no-current supply state.

An ignition coil for an internal combustion engine includes a primary bobbin including a winding cylinder part and a connection part between the winding cylinder part and a connector part, a primary coil including a primary main coil and a primary sub coil, and a secondary coil. When one of the primary main coil and the primary sub coil that includes an innermost coil part around the winding cylinder part is defined as a firstly-wound coil and the other is defined as a secondly-wound coil, firstly-wound ends, which are ends of the firstly-wound coil, and secondly-wound ends, which are ends of the secondly-wound coil, are attached to the connection part, and a shortest distance from a central axis of the winding cylinder part to each of the firstly-wound ends is smaller than a shortest distance from the central axis of the winding cylinder part to each of the secondly-wound ends.

The present invention relates to an ignition coil for generating a high-voltage pulse with a superimposed high-frequency voltage. The ignition coil comprises a first coil arranged on the primary side, a second coil arranged on the secondary side, a magnetic core and a third coil. The windings of the first coil and of the second coil are wound around the magnetic core. The second coil and the third coil are electrically connected to one another. A high-frequency terminal, which receives the high-frequency voltage, is electrically connected to the second coil and to the third coil.

Methods and systems are provided for multiplexing ignition signals in an engine system based on engine operating conditions, each cylinder of the engine system including a main chamber spark plug and a pre-chamber system. In one example, a method may include multiplexing spark signals to a first spark plug and a second spark plug, the first spark plug coupled to a pre-chamber of a first cylinder and the second spark plug coupled to a main chamber of a second cylinder. In this way, one ignition coil may be used to actuate two different spark plugs coupled to separate cylinders.

The objective is to provide an internal-combustion-engine controller that can diagnose a smolder state in a subsidiary combustion chamber of a subsidiary-chamber-type internal combustion engine at low cost and in real time and that can perform control so as to securely produce a spark discharge. The controller controls an internal combustion engine in which a fuel-air mixture in the main combustion chamber is ignited with combustion gas to be injected through an orifice provided in a subsidiary combustion chamber; the controller includes an ignition plug and a detection probe arranged in the subsidiary combustion chamber, an ignition coil, a fuel injector, a smolder detector, and a smolder diagnosis device, and controls at least one of the ignition coil and the fuel injector in accordance with a diagnostic result in the smolder diagnosis device.

The internal-combustion-engine combustion state control apparatus includes an ignition control means that generates two or more ignition signals during a single compression stroke or a single combustion stroke of an internal combustion engine, a high voltage means that makes an ignition plug, provided in a combustion chamber of the internal combustion engine, perform an ignition discharge based on the ignition signal, an ignition-discharge parameter detection circuit that detects a parameter indicating a state of the ignition discharge, an ignition-discharge duration detection means that detects two or more ignition discharge durations, based on an output signal of the ignition-discharge parameter detection circuit, and an abnormal-combustion determination means that diagnoses a combustion state of the internal combustion engine, based on at least one of the two or more ignition discharge durations; an abnormal-combustion-suppression control means is made to operate based on the result of a determination by the abnormal-combustion determination means.

An ignition coil for an internal combustion engine includes a primary bobbin including a winding cylinder part and a connection part between the winding cylinder part and a connector part, a primary coil including a primary main coil and a primary sub coil, and a secondary coil. When one of the primary main coil and the primary sub coil that includes an innermost coil part around the winding cylinder part is defined as a firstly-wound coil and the other is defined as a secondly-wound coil, firstly-wound ends, which are ends of the firstly-wound coil, and secondly-wound ends, which are ends of the secondly-wound coil, are attached to the connection part, and a shortest distance from a central axis of the winding cylinder part to each of the firstly-wound ends is smaller than a shortest distance from the central axis of the winding cylinder part to each of the secondly-wound ends.