Dual Ignition Coil Control for Engine Spark Plug

Solution Overview

Problem

The existing ignition devices for internal combustion engines require a large number of ignition coils to prevent ignition failure, leading to increased size and cost, which is undesirable.

Innovation Solution

A control device that uses two ignition coils to supply electric energy to a spark plug, with a discharge amount detection unit to estimate the supplyable voltage and control the energization of the second coil when the difference between the estimated and required voltage is below a threshold, allowing for efficient energy distribution without increasing the number of coils.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a large number of ignition coils are provided to supply sufficient electric energy to the spark plug, then the ignitability of the fuel is improved, but the size and cost of the ignition device increases

Engineering Contradiction:

ImproveignitabilityVSAvoidnumber of ignition coils

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The system performs preliminary detection of the first ignition coil's supplyable voltage before the second ignition coil is energized. This advance knowledge allows the control unit to make an informed decision about whether the second coil is needed, enabling proactive energy management rather than reactive addition of components.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The control unit continuously monitors the supplyable voltage from the first ignition coil and uses this feedback information to dynamically control the energization of the second ignition coil. This closed-loop control ensures that the second coil is activated only when necessary, optimizing the balance between ignitability and component usage.

Inventive Principle:

Principle #23Feedback

2Reliability

If a large number of ignition coils are provided to supply sufficient electric energy to the spark plug, then the ignitability of the fuel is improved, but the cost of the ignition device increases

Engineering Contradiction:

ImproveignitabilityVSAvoidcost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The system performs preliminary detection of the first ignition coil's supplyable voltage before the second ignition coil is energized. This advance knowledge allows the control unit to make an informed decision about whether the second coil is needed, enabling proactive energy management rather than reactive addition of components.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The control unit continuously monitors the supplyable voltage from the first ignition coil and uses this feedback information to dynamically control the energization of the second ignition coil. This closed-loop control ensures that the second coil is activated only when necessary, optimizing the balance between ignitability and component usage.

Inventive Principle:

Principle #23Feedback

3Reliability

If multiple ignition coils are used to prevent ignition failure, then the reliability of ignition is improved, but the size of the ignition device increases

Engineering Contradiction:

Improveignition reliabilityVSAvoidsize of ignition device

Core Design Contradiction:

ReliabilityVSWeight of stationary object

Solution Approach 1:

The system performs preliminary detection of the first ignition coil's supplyable voltage before the second ignition coil is energized. This advance knowledge allows the control unit to make an informed decision about whether the second coil is needed, enabling proactive energy management rather than reactive addition of components.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The control unit continuously monitors the supplyable voltage from the first ignition coil and uses this feedback information to dynamically control the energization of the second ignition coil. This closed-loop control ensures that the second coil is activated only when necessary, optimizing the balance between ignitability and component usage.

Inventive Principle:

Principle #23Feedback

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach improves ignitability while maintaining a reduced number of ignition coils, thereby reducing the size and cost of the ignition device.

Implementation Method 1

a discharge amount detection unit which detects a voltage between electrodes of the spark plug

Methodology Applied

Scientific EffectVoltage detection: Ohm's Law

Implementation Method 2

an ignition control unit which controls energization of a first ignition coil and a second ignition coil which each provide electric energy to a spark plug

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentUS11274646B2Control device for internal combustion engine

Publication Date: 2022.03.15 ASTEMO LTD

AI summary

Ignitability of a fuel by a spark plug is improved while an increase in the number of ignition coils is suppressed. A control device for an internal combustion engine includes an ignition control unit 83 which controls energization of an ignition coil 300a and an ignition coil 300b which each provide electric energy to a spark plug which discharges in a cylinder of an internal combustion engine to ignite a fuel, and a discharge amount detection unit which detects an inter-electrode voltage of the spark plug. After the ignition control unit 83 discharges the spark plug using the electric energy of the ignition coil 300a, the ignition control unit estimates a voltage which is supply-able from the ignition coil 300a to the spark plug, and controls energization of the ignition coil so as to supply the electric energy of the second ignition coil 300b to the spark plug when a difference d between the estimated supply-able voltage and a required voltage based on the voltage detected by the discharge amount detection unit is equal to or less than a predetermined threshold value.