Cover Member Attachment Structure for Internal Combustion Engine

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional oil seal come-off prevention apparatuses in internal combustion engines fail to maintain sufficient sealing performance due to positional deviations caused by thermal deformation of the housing, leading to potential oil leakage.

Innovation Solution

An internal combustion engine design featuring a cover member with multiple attachment portions and a seal member that restricts deformation near the oil seal securing portion, using fastening members to secure the cover member to the engine body, thereby preventing positional deviations and ensuring reliable sealing performance without the need for additional oil seal fall-off prevention members.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If the housing is deformed due to thermal strain, then the opening of the housing is deformed, but this causes positional deviation of the oil seal and insufficient sealing performance

Engineering Contradiction:

Improvethermal strainVSAvoidsealing performance

Core Design Contradiction:

TemperatureVSReliability

Solution Approach 1:

The cover member is divided into multiple attachment portions (first main body attachment portion near the oil seal securing portion, and second main body attachment portion at the edge portion), each independently fastened to different parts of the internal combustion engine main body. This segmentation allows differential movement absorption while maintaining overall structural integrity and sealing performance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A seal member is introduced as an intermediary element between the cover member and the internal combustion engine main body. The seal member absorbs thermal expansion and shrinkage, acting as a buffer that accommodates dimensional changes while maintaining the sealing function.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If multiple attachment portions are used to restrict deformation, then sealing performance is improved, but device complexity increases

Engineering Contradiction:

Improvesealing performanceVSAvoidattachment structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The first fastening member serves multiple functions: it attaches the first main body attachment portion to the internal combustion engine main body, and simultaneously acts as an oil seal fall-off prevention member by restricting the oil seal from falling off. This multi-functionality reduces the need for separate components and simplifies the overall device structure.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The oil seal fall-off prevention function is merged with the fastening function of the first fastening member. Instead of being a separate component, the fastening member's structure inherently provides the fall-off prevention capability, thereby reducing device complexity while maintaining sealing performance.

Inventive Principle:

Principle #5Merging (Combining)

3Reliability

If the cover member is rigidly fixed to prevent deformation, then sealing performance is maintained, but thermal expansion and shrinkage cannot be absorbed

Engineering Contradiction:

Improvesealing performanceVSAvoidthermal deformation

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

The inner diameter of the second main body attachment portion is specifically designed to generate a clearance that can absorb positional deviations caused by thermal expansion and shrinkage. By controlling the dimensional parameters of the attachment portion, the system accommodates thermal variations while maintaining sealing effectiveness.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

A clearance is pre-designed in the second main body attachment portion to accommodate future thermal expansion and shrinkage. This beforehand cushioning allows the cover member to move within acceptable limits during thermal cycles without compromising the sealing performance or causing excessive stress.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

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

The solution effectively maintains sufficient sealing performance by restricting deformation and positional deviations, preventing oil leakage and simplifying the configuration by integrating the oil seal fall-off prevention function, while also absorbing thermal expansion and shrinkage through strategically designed clearances.

Implementation Method 1

the clearance includes a size which is absorbable a positional deviation of the second main body attachment portion which is caused by at least one of thermal expansion of the cover member and thermal shrinkage of the cover member

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Implementation Method 2

a seal member arranged between the cover member and the internal combustion engine main body

Methodology Applied

Scientific EffectElasticity: Elasticity

Data Source

PatentEP3070376B1Internal combustion engine and cover member attachment structure for internal combustion engine

Publication Date: 2018.02.14 AISIN SEIKI KK

Figure 1
Figure 2~3
Figure 4~5

AI summary

This internal combustion engine includes an oil seal attached to a crankshaft of an internal combustion engine main body, and a cover member including an oil seal securing portion for securing the oil seal attached to the crankshaft, the cover member including a first main body attachment portion which is arranged in a vicinity of the oil seal securing portion and which is for attaching the cover member to the internal combustion engine main body by a first fastening member.