Cylinder Head Recessed Section Orientation for Weight and Efficiency

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing cylinder head designs face a trade-off between combustion efficiency improvement and weight reduction, particularly when a tumble control valve is attached, as the space required for the bearing limits the size of recessed sections, hindering effective weight reduction while compromising combustion efficiency.

Innovation Solution

The cylinder head features recessed sections that open towards the bottom wall section, allowing for a thinner space between intake passages, which inhibits shrinkage cavities and enables balanced combustion efficiency and weight reduction, achieved through strategic mold design and casting processes, including pressure die casting with a mold having high thermal conductivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Weight of moving object

If recessed sections are formed between intake ports to reduce cylinder head weight, then weight reduction is achieved, but the recessed section size is limited by bearing space when tumble control valve is attached, reducing weight reduction effect

Engineering Contradiction:
Improvecylinder head weightVSAvoidcombustion efficiency improvement
Core Design Contradiction:
Weight of moving objectVSAdaptability or versatility

Solution Approach 1:

The recessed section is configured to open toward the bottom surface direction rather than the contact plane direction, utilizing the vertical dimension below the intake passages. This dimensional reorientation allows the recessed section to extend downward between the intake passages without interfering with the bearing space required for the tumble control valve, thereby enabling greater weight reduction while maintaining combustion efficiency improvement capabilities

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Weight of moving object

If recessed section size is increased for weight reduction, then weight reduction effect is enhanced, but space for bearing is reduced, compromising combustion efficiency

Engineering Contradiction:
Improvecylinder head weightVSAvoidcombustion efficiency
Core Design Contradiction:
Weight of moving objectVSReliability

Solution Approach 1:

By orienting the recessed section to open toward the bottom surface rather than the contact plane, the invention utilizes the vertical space below the intake passages. This allows the recessed section to achieve sufficient size for effective weight reduction while the bearing for the tumble control valve maintains its required space between the intake passages, thus preserving combustion efficiency

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Weight of moving object

If space between intake passages is reduced for weight reduction, then weight reduction is achieved, but shrinkage cavities may occur during casting

Engineering Contradiction:
Improvecylinder head weightVSAvoidshrinkage cavities
Core Design Contradiction:
Weight of moving objectVSObject-affected harmful factors

Solution Approach 1:

The recessed section is strategically positioned and configured to open toward the bottom surface, creating localized thinning of the metal section between intake passages precisely where shrinkage cavities are most likely to occur during casting. This local quality modification effectively prevents shrinkage cavities while maintaining overall structural integrity and achieving weight reduction

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 effectively balances combustion efficiency improvement and weight reduction, preventing shrinkage cavities and enhancing fuel economy, while maintaining quality and preventing excess fuel injection by controlling fuel injection amounts based on intake flow rates.

Implementation Method 1

the recessed section is configured to be formed by using a part of the mold

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentEP3244050B1Internal combustion engine equipped with a cylinder head, and internal combustion engine equipped with a cylinder head manufacturing method
Publication Date: 2019.12.18 AICHI MASCH IND CO LTD
  • EP3244050B1 patent drawingFigure 1
  • EP3244050B1 patent drawingFigure 2
  • EP3244050B1 patent drawingFigure 3

AI summary

[Object] To provide a technique for contributing to the balance of combustion efficiency improvement and weight reduction. [Resolution Means] A recessed section (35), provided in the space between a second intake passage (322) and a third intake passage (323) of the spaces between each intake passage (32), is formed on a lower wall (27b) of an attachment part (27) so as to open toward the direction that a lower deck (24) is facing, not toward the direction that a contact plate (27a) is facing. This allows the size of the recessed section (35) to not be limited, even in the case that a bearing member (58) is disposed in the space between the second intake passage (322) and the third intake passage (323) to rotatably support a valve shaft (54) due to providing a tumble control valve device (50) on an attachment flange part (46) of an intake manifold (4). This allows a balance of combustion efficiency improvement and weight reduction of an internal combustion engine (1) to be achieved.