US 10,801,461 B2Granted

Ignition apparatus

AssigneeDenso Corporation

InventorsYasuomi Imanaka, Kaori Doi

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Abstract

An ignition apparatus performs energy input control in which energy is continuously inputted to an ignition coil to enable a spark discharge in a predetermined energy input period after interrupting a primary current by an ignition switch and generating a discharge of a spark plug by a secondary current. A combustion state determination circuit determines a combustion state by comparing a combustion pressure P detected by a combustion state detector. When the combustion pressure P is smaller than a second threshold Pth2, and there is room for improving the combustion state with respect to the present energy input condition, the energy input period IGW is increased or a target secondary current I2* is increased. By compensating the condition of the energy input control in accordance with the combustion state, a target combustion state can be achieved with just enough energy consumption.

Claims8

Dependent claims

An ignition apparatus for controlling operation of a spark plug for igniting an air-fuel mixture in a combustion chamber of an internal combustion engine, comprising:

an ignition coil including a primary coil through which a primary current supplied from a DC power supply flows, and a secondary coil which is connected to an electrode of the spark plug and in which a secondary voltage occurs due to conduction and interruption of the primary current causing a secondary current to flow therethrough;
an ignition switch which is connected to a ground side opposite to the DC power supply of the primary coil and intermits the primary current in accordance with an ignition signal;
an energy input section configured to input energy to the primary coil of the ignition coil with a same polarity as the secondary current in a predetermined energy input period after the primary current is interrupted by the ignition switch and a discharge of the spark plug is generated by the secondary voltage due to the interruption;
an input energy control section configured to control the input energy;
and
a combustion state determination section configured to acquire information from a combustion state detector for detecting a combustion state in the combustion chamber, and determines the combustion state based on the information, wherein:
the input energy control section is further configured to compensate a control value of the input energy in accordance with the determined combustion state;
the energy input section is further configured to input the energy to the primary coil of the ignition coil with the same polarity as the secondary current flowed by the discharge of the spark plug, and the secondary voltage is generated due to the primary current being interrupted by the ignition switch being turned off after the primary current starts to flow due to the ignition switch being turned on;
the energy input section includes a rectifying element configured to being connected to the ground side of the primary coil, interrupt a current which flows in the direction to a ground, and flow a current to the ground side of the primary coil from the ground;
and
the rectifying element is configured to flow a current to the ground side of the primary coil from the ground even if the primary current is interrupted by the ignition switch being turned off.

8 more elements

An ignition apparatus for controlling operation of a spark plug for igniting an air-fuel mixture in a combustion chamber of an internal combustion engine, comprising:

an ignition coil including a primary coil through which a primary current supplied from a DC power supply flows, and a secondary coil which is connected to an electrode of the spark plug and in which a secondary voltage occurs due to conduction and interruption of the primary current causing a secondary current to flow therethrough;
an ignition switch which is connected to a ground side opposite to the DC power supply of the primary coil and intermits the primary current in accordance with an ignition signal;
an energy input section configured to input energy to the primary coil of the ignition coil with a same polarity as the secondary current in a predetermined energy input period after the primary current is interrupted by the ignition switch and a discharge of the spark plug is generated by the secondary voltage due to the interruption;
an input energy control section configured to control the input energy;
and
a combustion state determination section configured to acquire information from a combustion state detector for detecting a combustion state in the combustion chamber, and determines the combustion state based on the information, wherein:
the input energy control section is further configured to compensate a control value of the input energy in accordance with the determined combustion state;
the energy input section is further configured to input the energy to the primary coil of the ignition coil with the same polarity as the secondary current flowed by the discharge of the spark plug, and the secondary voltage is generated due to the primary current being interrupted by the ignition switch being turned off after the primary current starts to flow due to the ignition switch being turned on;
the energy input section includes a capacitor, a switch and a rectifying element;
and
the capacitor, the switch and the rectifying element form a structure that is configured to input energy with the same polarity as the secondary current to the ignition coil from the ground side of the primary coil.

8 more elements

Dependencies are inferred from the claim text.

Facts

Application: 15/302,034Filed 2 Apr 2015
Priority: JP 2014-08065710 Apr 2014
Published: US 2017/0122281 A14 May 2017
Granted: 13 Oct 2020
Term ends: Not estimatedThe source records don’t support an estimate.

Classification18 codes

F02P 3/05
Layout of circuits: for control of the magnitude of the current in the ignition coil
F02P 3/0892
Closing the discharge circuit of the storage capacitor with semiconductor devices: using digital techniques
F02P 5/1502
Digital data processing: using one central computing unit
F02P 15/10
Electric spark ignition having characteristics not provided for in, or of interest apart from, groups F02P1/00 - F02P13/00 and combined with…:…