Composite Connecting Rod Assembled Shells Core Elimination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The production of composite material connecting rods is complex due to the need for a core to maintain the desired shape during resin hardening, which is difficult to extract and can be heavy and fragile, and existing methods restrict optimal fiber orientation, leading to suboptimal mechanical performance and increased costs.
Innovation Solution
A structural connecting rod composed of assembled shells with bearing surfaces, allowing for simultaneous polymerization or assembly through gluing, welding, or mechanical fasteners, eliminating the need for a single-use core and enabling optimal fiber orientation for improved mechanical properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a core is used to maintain the desired shape during resin hardening, then the connecting rod can be produced with the correct geometry, but the core extraction becomes difficult and increases production complexity
Solution Approach 1:
The core is extracted from the hardened composite connecting rod through a specialized process involving heating to soften the composite material and mechanical extraction tools. This resolves the contradiction by successfully removing the core after it has served its shaping function, achieving both geometric accuracy and core removal.
Solution Approach 2:
The core is designed with preliminary extraction features such as fragmentation zones and extraction channels that are built into the core structure before production. This allows for easier subsequent extraction by preparing the extraction path in advance, reducing the complexity of the removal process.
2Manufacturing precision
If a single-use core is used to produce the connecting rod, then the desired shape can be achieved, but the core mass increases the overall production cost
Solution Approach 1:
The core is designed as a thin-walled hollow structure rather than a solid mass, maintaining sufficient rigidity to define the connecting rod geometry while minimizing material usage and overall mass, thus reducing production costs.
3Ease of manufacture
If conventional fiber winding methods are used, then the connecting rod can be manufactured, but the fiber orientation is restricted and mechanical performance is suboptimal
Solution Approach 1:
The connecting rod is divided into multiple segments or zones, each with optimized fiber orientation tailored to the specific stress conditions in that region. This allows for superior mechanical performance in each zone while maintaining manufacturing feasibility through modular construction.
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 approach simplifies the production of composite material connecting rods with enhanced mechanical performance and reduced costs by allowing for easier assembly and optimal fiber orientation, reducing the complexity and mass of the core extraction process.
Implementation Method 1
the resin of the composite material has hardened, generally by polymerization during a thermal hardening cure
Data Source
Figure 1
Figure 2~3b
Figure 4a~7b
AI summary
A connecting rod (2) is composed of two or more assembled shells (3a, 3b) made of a composite, open over the entire length of the connecting rod. The shells incorporate clevis joints (231a, 231b, 232a, 232b) for introducing stress at each of their ends. The shells are produced separately then assembled together to form a sealed section. Each shell is made from a material preimpregnated with long fibres. The production of each shell is simplified due to the overall shape of the shell as a simple curve, thus a shell may be produced industrially, for example, by thermoforming a flat composite preform. The two shells are assembled by simultaneous polymerization of the shells, by bonding, by welding, by riveting or any other assembly process or combination of assembly processes that are compatible with one another. The structural composite connecting rod obtained has very good mechanical properties, especially in compression, with a simple and economic production process.