Engine Ignition Control Device Timing Synchronization

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Solution Overview

Problem

In hybrid vehicles, the timing mismatch between the application of electric assist torque from the motor to the internal combustion engine's crankshaft and the combustion initiation timing can lead to unstable ignition starts, potentially resulting in combustion failures.

Innovation Solution

An electronic control unit adjusts the initiation timing of sparking and the electric assist torque based on real-time crank angle acceleration and torque indication values, using maps to correct deviations and detect abnormalities in the clutch system, ensuring synchronization between clutch engagement and combustion initiation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the timing of electric assist torque application is advanced to ensure sufficient torque for ignition start, then the reliability of engine start is improved, but the timing mismatch with combustion initiation increases causing unstable ignition

Engineering Contradiction:
Improveignition start reliabilityVSAvoidtiming synchronization precision
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The control device detects actual crank angle acceleration during ignition start and compares it with predetermined thresholds. Based on this feedback, the control device determines whether timing mismatch occurred and adjusts the electric assist torque application timing accordingly for the next ignition start,实现闭环控制

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent replaces mechanical timing adjustment mechanisms with electronic control. The ECU calculates and adjusts the electric assist torque application timing based on detected crank angle acceleration, substituting mechanical synchronization methods with electronic sensing and control

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If the initiation timing of sparking is advanced to ensure combustion occurs, then combustion reliability is improved, but timing mismatch with clutch engagement increases causing combustion failure

Engineering Contradiction:
Improvecombustion reliabilityVSAvoidtiming coordination precision
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The control device uses detected crank angle acceleration to determine whether timing mismatch occurred between sparking and clutch engagement. Based on this feedback, it adjusts the sparking initiation timing for subsequent operations,实现动态时序校正

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent makes the sparking timing dynamic rather than fixed. The ECU adjusts the sparking initiation timing based on real-time detection of crank angle acceleration and determination of timing mismatch, enabling adaptive timing coordination

Inventive Principle:
Principle #15Dynamics

3Manufacturing precision

If clutch engagement timing is delayed to match combustion initiation, then timing synchronization is improved, but the torque support duration for crankshaft rotation is insufficient reducing start reliability

Engineering Contradiction:
Improvetiming synchronization precisionVSAvoidignition start reliability
Core Design Contradiction:
Manufacturing precisionVSReliability

Solution Approach 1:

The control device detects crank angle acceleration and determines whether timing mismatch occurred. Based on this feedback, it adjusts the clutch engagement timing and electric assist torque application timing to prevent future mismatches,实现预防性校正

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP3175101B1Control device for starting an engine of a vehicle
Publication Date: 2021.08.25 TOYOTA JIDOSHA KK
  • EP3175101B1 patent drawingFigure 1
  • EP3175101B1 patent drawingFigure 2(A)~2(G)
  • EP3175101B1 patent drawingFigure 3A~3B

AI summary

A control device for a vehicle includes an electronic control unit which executes electric assist of rotation of an engine crankshaft by a motor in association with engagement of a clutch, at the time of an ignition start in which fuel injection and sparking are executed with respect to a target cylinder, which has been stopped in an expansion stroke. The electronic control unit corrects at least one of the initiation timing of sparking (204) which is to be initially performed in the target cylinder at the time of the ignition start and an electric assist torque (204, 208) which is to be used for the ignition start, on the basis of a combination of the relationship between an acquisition value and an estimation value of a torque indication value, and the relationship between an acquisition value and an estimation value of an ignition delay time (200, 202, 208).