Internal Combustion Engine Fuel Injection Control

Solution Overview

Problem

In internal combustion engines with two intake valves connected to a cylinder, differing opening timings can lead to non-uniform mixture gas in the cylinder, resulting in unburnt HC emissions and carbon deposition due to uneven fuel injection.

Innovation Solution

The engine is configured with a fuel injection control unit that advances the opening timing of the first intake valve relative to the second, allowing for exhaust stroke fuel injection to the earlier-opening intake port, promoting mixing and gasification by utilizing backflow, and adjusting valve opening phases to optimize fuel injection timing based on engine operating states.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If the opening timings of two intake valves are made different, then the fuel mixing and gasification are promoted, but the uniformity of mixture gas in the cylinder is reduced

Engineering Contradiction:

Improvefuel mixing efficiencyVSAvoiduniformity of mixture gas

Core Design Contradiction:

Use of energy by moving objectVSStability of the object's composition

Solution Approach 1:

Fuel injection is performed in advance during the exhaust stroke for the intake port with the earlier-opening intake valve. This preliminary action allows the fuel to mix with the backflow of exhaust gas before the intake stroke begins, promoting fuel gasification and mixing while compensating for the timing difference between the two intake valves.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

Different fuel injection strategies are applied to different intake ports based on their valve opening timings. The intake port with the earlier-opening valve receives exhaust stroke injection to promote mixing, while the other intake port uses standard intake stroke injection, creating localized optimization for each port's specific conditions.

Inventive Principle:

Principle #3Local quality

2Device complexity

If the fuel injection timing is the same for both intake valves, then the control is simplified, but the fuel enters the cylinder in the form of droplets leading to unburnt HC emission or carbon deposition

Engineering Contradiction:

Improvecontrol complexityVSAvoidunburnt HC emission

Core Design Contradiction:

Device complexityVSObject-generated harmful factors

Solution Approach 1:

Fuel injection is performed in advance during the exhaust stroke for the intake port with the earlier-opening intake valve. This preliminary action allows the fuel to mix with the backflow of exhaust gas before the intake stroke begins, promoting fuel gasification and mixing while compensating for the timing difference between the two intake valves.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The fuel injection timing is made dynamic and adaptive based on the valve opening timings. Instead of using a fixed injection timing for both ports, the system adjusts the injection timing for each intake port according to its specific valve opening characteristics, allowing optimal fuel atomization and mixing under varying conditions.

Inventive Principle:

Principle #15Dynamics

3Device complexity

If the fuel injection timing is the same for both intake valves, then the injection control is simplified, but the mixture gas uniformity is reduced

Engineering Contradiction:

Improveinjection control complexityVSAvoidmixture gas uniformity

Core Design Contradiction:

Device complexityVSStability of the object's composition

Solution Approach 1:

Fuel injection is performed in advance during the exhaust stroke for the intake port with the earlier-opening intake valve. This preliminary action allows the fuel to mix with the backflow of exhaust gas before the intake stroke begins, promoting fuel gasification and mixing while compensating for the timing difference between the two intake valves.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

Different fuel injection strategies are applied to different intake ports based on their valve opening timings. The intake port with the earlier-opening valve receives exhaust stroke injection to promote mixing, while the other intake port uses standard intake stroke injection, creating localized optimization for each port's specific conditions.

Inventive Principle:

Principle #3Local quality

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 configuration enhances fuel mixing and gasification, reducing non-uniformity and emissions of unburnt HC or carbon deposition by ensuring efficient fuel utilization and combustion.

Implementation Method 1

promoting mixing and gasification by utilizing backflow

Methodology Applied

Scientific EffectBackflow:

Data Source

PatentEP3002440B1Internal combustion engine

Publication Date: 2017.11.29 MITSUBISHI MOTORS CORP

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AI summary

To control fuel injection timings to two intake ports of a cylinder to promote mixing and gasification of the fuel, the internal combustion engine includes a first intake port (7a) and a second intake port (7b) which are connected to a cylinder (9), a first intake valve (15a) of the first intake port (7a), a second intake valve (15b) of the second intake port (7b), a first fuel injection valve (19a) for injecting fuel to the first intake port (7a), a second fuel injection valve (19b) for injecting fuel to the second intake port (7b), and a fuel injection control unit (65). The first intake valve (15a) is configured so that an opening timing of the first intake valve (15a) is advanced relative to an opening timing of the second intake valve (15b). The fuel injection control unit (65) is configured to perform fuel injection by the first fuel injection valve (19a) in advance of injection timing of the second fuel injection valve (19b).