Cylinder Crankcase Cooling via Machined Coolant Jacket

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for producing cylinder crankcases with wet hanging liners require additional cores for water jacket formation, leading to increased effort and material usage, especially in die-casting, and result in thick-walled bushings for strength and cooling, which are heavy and costly.

Innovation Solution

Mechanical processing of side walls to create axial sections with varying diameters forms a coolant jacket without additional cores, allowing for optimal cooling and precise bushing positioning, eliminating the need for water jacket cores and enabling thinner bushings for reduced weight and distortion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If water jacket cores are used to form coolant channels, then cooling is achieved, but additional manufacturing effort and material usage increase

Engineering Contradiction:
Improvecooling efficiencyVSAvoidmanufacturing process complexity
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The invention extracts and eliminates the water jacket core from the manufacturing process. Instead of using a core to form the coolant channel cavity, the method uses direct machining of the cylinder chamber walls after casting to create the coolant passage. This removes the additional step of core insertion and extraction, simplifying the manufacturing process while maintaining effective cooling.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention applies preliminary action by providing machining allowances on the cylinder chamber walls during the initial casting process. These allowances are prepared in advance to enable subsequent machining operations that will create the coolant channels. This preliminary preparation eliminates the need for complex core formation while ensuring proper cooling channel geometry.

Inventive Principle:
Principle #10Preliminary action

2Strength

If thick-walled bushings are used for strength and cooling, then durability is improved, but weight increases

Engineering Contradiction:
Improvebushing strengthVSAvoidcrankcase weight
Core Design Contradiction:
StrengthVSWeight of moving object

Solution Approach 1:

The invention changes the wall thickness parameter of the bushings by eliminating the need for thick walls to accommodate water jacket cores. With the coreless design, thinner-walled bushings can be used while maintaining sufficient structural strength and cooling effectiveness, as the coolant channels are formed directly in the crankcase material surrounding the bushings.

Inventive Principle:
Principle #35Parameter changes

3Temperature

If additional cores are inserted and removed, then water jacket formation is achieved, but manufacturing time and cost increase

Engineering Contradiction:
Improvecoolant channel formationVSAvoidmanufacturing efficiency
Core Design Contradiction:
TemperatureVSProductivity

Solution Approach 1:

The invention extracts the water jacket core from the process entirely and replaces it with a machining operation. This eliminates the time-consuming steps of core insertion, positioning, and subsequent removal, thereby improving manufacturing efficiency and productivity while still achieving the necessary coolant channel formation.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention substitutes the mechanical core-based system with a machining-based system. Instead of using physical cores to form the coolant channels, the method uses machining operations on the cast cylinder chamber walls to create the passages. This substitution simplifies the manufacturing process and improves productivity by eliminating complex core handling operations.

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

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 method achieves efficient cooling with minimal material usage and reduced weight, eliminating the need for core production and processing, resulting in a cost-effective and lightweight cylinder crankcase with precise cooling and improved engine stability.

Implementation Method 1

at least one steel quill is inserted into the mold to form at least one cylinder chamber

Methodology Applied
Scientific EffectDisplacement:

Implementation Method 2

By machining the side walls bounding the at least one cylinder chamber before inserting the liners

Methodology Applied
Scientific EffectMachining:

Implementation Method 3

a free space for forming a coolant jacket is created between a first section of larger diameter and a third axial section of smaller diameter

Methodology Applied
Scientific EffectConvection cooling: Convection

Data Source

PatentEP2738377B1Process for manufacturing a cylinder crankcase
Publication Date: 2021.04.28 KS HUAYU ALUTECH GMBH
  • EP2738377B1 patent drawingFigure 1~2
  • EP2738377B1 patent drawingFigure 3

AI summary

Producing cylinder crankcase (10) comprising wet- and hanging bushes (16), comprises closing a casting mold, introducing at least one steel sleeve into the casting mold for forming at least one cylinder chamber (14), filling the casting mold with a molten metal, extending the steel sleeve after solidification of the melt, opening the mold, removing the cylinder crankcase from the casting mold, and inserting a wet hanging bush into the respective cylinder chambers. The sidewalls bounding the cylinder chamber, before inserting the bushes, are mechanically processed. Producing cylinder crankcase (10) comprising wet- and hanging bushes (16), comprises (a) closing a casting mold, (b) introducing at least one steel sleeve into the casting mold for forming at least one cylinder chamber (14), (c) filling the casting mold with a molten metal, (d) extending the steel sleeve after solidification of the melt, (e) opening the mold, (f) removing the cylinder crankcase from the casting mold, and (g) inserting a wet hanging bush into the respective cylinder chambers formed by the steel sleeve. The sidewalls bounding the cylinder chamber, before inserting the bushes, are mechanically processed, in which a first section of larger diameter is produced between a second axial section of smaller diameter and a third axial section of smaller diameter, which are formed by the steel sleeve.