Internal Combustion Engine Crank Chamber Segmentation for Blow-by Gas Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing internal combustion engines face issues with turbulent airflow and oil separation due to unexpected flow patterns in the crank and oil chambers, leading to excessive oil flow into the oil separator and inefficient separation.

Innovation Solution

The internal combustion engine design includes specific configurations such as separate crank chambers, an oil chamber connected to these chambers, and blow-by gas passages to the oil separator, with connecting paths between crank chambers that prevent direct connection between certain chambers, ensuring symmetrical airflow and reducing turbulent flow, thereby controlling oil flow effectively.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If blow-by gas passages are provided to guide gas from the oil chamber to the oil separator, then oil separation is enabled, but excessive oil may flow into the oil separator or oil separation becomes inappropriate due to unexpected turbulent flow

Engineering Contradiction:
Improveoil separation effectivenessVSAvoidturbulent flow
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The crank chamber is divided into multiple separate crank chambers (first, second, third, fourth crank chambers) that are connected through connecting paths. This segmentation allows control over gas flow patterns between chambers, preventing unexpected turbulent flow while maintaining effective oil separation through the blow-by gas passages.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The third wall is designed without a passage connecting the second and third crank chambers, creating a specific local flow restriction. This local quality change directs gas flow through controlled paths, reducing turbulent flow in the oil chamber while maintaining effective oil separation functionality.

Inventive Principle:
Principle #3Local quality

2Reliability

If connecting paths are provided between crank chambers, then gas flow control is improved, but device complexity increases due to additional walls and passages

Engineering Contradiction:
Improveairflow controlVSAvoidcrank chamber structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

Multiple crank chambers are merged into a single crankcase structure with shared walls and connecting paths. The first, second, third, and fourth crank chambers are integrated within the same crankcase, reducing overall structural complexity while maintaining the benefits of controlled gas flow between chambers.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The walls serving as separators between crank chambers also function as structural components of the crankcase and provide pathways for gas flow. For example, the second wall separates the first and second crank chambers while also providing a connecting path between them, achieving multiple functions with a single structural element.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP4242432B1Internal combustion engine
Publication Date: 2025.01.15 TOYOTA JIDOSHA KK
  • EP4242432B1 patent drawingFigure 1
  • EP4242432B1 patent drawingFigure 2
  • EP4242432B1 patent drawingFigure 3

AI summary

An internal combustion engine includes a first blow-by gas passage defined in a second wall. The internal combustion engine includes a second blow-by gas passage defined in a third wall. The internal combustion engine includes a third blow-by gas passage defined in a fourth wall. The first blow-by gas passage to the third blow-by gas passage connect an oil chamber and an oil separator to each other. The second wall includes a first connecting path. The fourth wall includes a second connecting path. The first connecting path connects the first crank chamber and the second crank chamber. The second connecting path connects the third crank chamber and the fourth crank chamber to each other. The third wall does not have a passage connecting the second crank chamber and the third crank chamber to each other.