CONTROL APPARATUS FOR INTERNAL COMBUSTION ENGINE

摘要

In an ignition control apparatus, a control unit controls switching elements so as to supply a primary current to the other end side of a primary winding opposite to one end thereof connected to a DC power source by discharging (which is performed by turning on a second switching element stored energy from a capacitor during ignition discharge (which is started by turning off a first switching element. In particular, the control unit controls the second switching element or the third switching element so as to provide variability to the amount of stored energy discharged from the capacitor according to an operating state of an internal combustion engine.

主权项

1. An ignition control apparatus configured to control operation of an ignition plug, which is provided to ignite a fuel-air mixture in a cylinder of an internal combustion engine, the apparatus comprising:
an ignition coil including a primary winding and a secondary winding and configured to increase/decrease a primary current, which passes through the primary winding, to generate a secondary current in the secondary winding connected to the ignition plug; a DC power source having a non-grounded side output terminal connected to one end side of the primary winding, so as to cause the primary current to pass through the primary winding; a first switching element configured as a semiconductor switching element including a first control terminal, a first power source side terminal, and a first grounded side terminal, and configured to control turn-on and turn-off of current supply between the first power source side terminal and the first grounded side terminal on the basis of a first control signal inputted to the first control terminal, the first switching element having the first power source side terminal connected to the other end side of the primary winding and the first grounded side terminal connected to the grounded side; a second switching element configured as a semiconductor switching element including a second control terminal, a second power source side terminal, and a second grounded side terminal, and configured to control turn-on and turn-off of current supply between the second power source side terminal and the second grounded side terminal on the basis of a second control signal inputted to the second control terminal; a third switching element configured as a semiconductor switching element including a third control terminal, a third power source side terminal, and a third grounded side terminal, and configured to control turn-on and turn-off of current supply between the third power source side terminal and the third grounded side terminal on the basis of the third control signal inputted to the third control terminal; an energy storing coil configured as an inductor interposed on a power line that connects the non-grounded side output terminal of the DC power source and the third power source side terminal of the third switching element to store energy when the third switching element is turned on; a capacitor disposed between the non-grounded side output terminal and the grounded side of the DC power source and connected in series with the energy storing coil to store energy when the third switching element is turned off; and a control unit provided to control the second switching element and the third switching element so as to supply the primary current to the primary winding from the other end side thereof by discharging the stored energy from the capacitor when the second switching element is turned on during ignition discharge of the ignition plug started by turning off the first switching element, the control unit controlling the second switching element or the third switching element so as to provide variability to the amount stored energy or the amount of stored energy discharged from the capacitor according to an operating state of the internal combustion engine.