Composite Spring Wire Winding for Torsional Strength and Weight Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wire materials for elastic members, such as coil springs, face issues with breakage due to diameter contraction under torsional loads, leading to reduced strength and rigidity, which hinders weight reduction and desired performance.
Innovation Solution
A wire material with a specific fiber winding configuration, where the angle between the outer circumferential reinforced fibers and the winding direction is 40° to 50°, and the ratio of the outer to inner fiber layer thickness is 0.5 or higher, along with a core member made of an elastically deformable material, providing a rigidity of 9 GPa or higher and static torsional strength of 540 MPa or more.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If fibers are wound around the core member in a mesh manner, then the wire material can be produced, but buckling breakage of fibers occurs when torsional stress is applied
Solution Approach 1:
The patent changes the winding angle parameter from a mesh pattern (typically 0° or random) to a specific angle range of 30° to 60° relative to the axial direction. This parameter change transforms the fiber arrangement to better withstand torsional stresses while maintaining manufacturability through standard winding processes.
Solution Approach 2:
The patent creates a composite structure combining the core member with fibers wound at specific angles. This composite configuration leverages the directional strength of fibers at optimized angles to resist torsional loads, creating a material that combines the advantages of both the core member and the angularly-oriented fiber reinforcement.
2Strength
If the diameter of the wire material is increased to ensure strength, then torsional strength is improved, but weight reduction effect is insufficient
Solution Approach 1:
Instead of increasing diameter, the patent changes the fiber winding angle parameter to 30°-60°, which optimizes the structural efficiency of the existing diameter. This allows the same strength to be achieved with a smaller, lighter diameter, or the same diameter to provide enhanced strength with weight savings.
Solution Approach 2:
The patent applies fiber reinforcement with specific local orientation (winding angle) where it is most needed to resist torsional stresses. This localized optimization of fiber orientation provides strength where required without adding unnecessary material elsewhere, achieving weight reduction while maintaining strength.
3Ease of operation
If the wire material undergoes diameter contraction under torsional load, then coil spring compression is enabled, but breakage of wire material occurs
Solution Approach 1:
The patent optimizes the fiber winding angle parameter to 30°-60° to balance the wire material's response to torsional loading. This angular optimization allows controlled diameter contraction for compression functionality while distributing stresses to prevent breakage, achieving both operational requirements and reliability.
4Ease of manufacture
If conventional fiber winding is used, then manufacturing is simple, but the strength and rigidity of the coil spring are lowered
Solution Approach 1:
The patent modifies the winding angle parameter from conventional mesh patterns to a specific range of 30° to 60°. This parameter change maintains compatibility with existing manufacturing processes while dramatically improving the strength and rigidity characteristics of the resulting wire material and coil spring.
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 achieves a balance of reduced weight and improved strength, enabling effective performance as a suspension spring with enhanced resistance to torsional stress while maintaining necessary deflection characteristics.
Implementation Method 1
an angle formed by the center axis of the winding of the outer circumferential-side reinforced fibers and the winding direction of the outer circumferential-side reinforced fibers is 40° to 50°
Implementation Method 2
the core member and the wire material for the elastic member have circular cross sections
Data Source
Figure 1
Figure 2~3
Figure 4A~4B
AI summary
A wire material for an elastic member according to the present invention is a wire material for an elastic member for producing an elastic member and includes inner circumferential-side reinforced fibers that are wound in a spiral form, outer circumferential-side reinforced fibers that are wound around the inner circumferential-side reinforced fibers, and thermosetting resin that is provided in at least a part of the inner circumferential-side reinforced fibers and the outer circumferential-side reinforced fibers and firmly fixes the reinforced fibers with each other. A winding direction of the inner circumferential-side reinforced fibers forms equal to or larger than 70° and equal to or smaller than 110° with respect to a center axis of the winding, and a winding direction of the outer circumferential-side reinforced fibers with respect to the center axis of the winding is along a direction of a tensile load that is applied to the wire material for the elastic member in accordance with a load applying torsional stress to the wire material for the elastic member as an externally applied load.