Partially Separated Fiber Bundle for Composite Molding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing fiber bundles with an optimal number of single fibers for composite material molding struggle with continuous separation without causing yarn breakage, especially when dealing with large tows containing twist, and often require frequent blade exchanges or result in suboptimal mechanical properties and flowability.
Innovation Solution
A method for producing a partially separated fiber bundle by alternately forming separation-processed and not-separation-processed sections, using a separation means with projected parts that penetrate and remove from the fiber bundle to create nonuniform divisions, allowing for continuous and stable slitting without worrying about blade exchange life, even with twisted or large tow fibers, and enabling optimal distribution of thin and thick fiber bundles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a fiber bundle with a large number of single fibers is used, then flowability at the time of molding is improved, but mechanical properties of the molded article deteriorate
Solution Approach 1:
The fiber bundle is divided into multiple sub-bundles with different numbers of single fibers through the separation processing. This segmentation allows the creation of a mixed fiber bundle containing both thin sub-bundles (fewer fibers) and thick sub-bundles (more fibers), thereby balancing flowability and mechanical properties in the molded article
2Manufacturing precision
If disk-shaped rotary blades are used for longitudinal slitting, then the number of single fibers can be adjusted, but the fiber bundle loses convergence property and becomes difficult to handle
Solution Approach 1:
Instead of longitudinally slitting the entire fiber bundle, the invention applies partial separation processing only to specific sections. The separation means (projected parts) are made to penetrate and remove from the fiber bundle in a repetitive manner, creating alternating separation-processed and not-separation-processed sections. This partial action maintains convergence property while still achieving the desired fiber number adjustment
3Ease of operation
If a separation cutter with longitudinal and lateral blades is used, then handling property is improved, but blade exchange frequency increases when one blade reaches cutting life
Solution Approach 1:
The invention extracts the cutting function from the system by eliminating the need for lateral blades. Instead of using a complex separation cutter with both longitudinal and lateral blades, the invention uses only projected parts that penetrate and remove from the fiber bundle. This simplification removes the blade exchange problem while maintaining effective separation capability
4Device complexity
If circumferential speed of roll and conveying speed are synchronized, then processing is simplified, but control over lengths of separated and not-separated sections becomes impossible
Solution Approach 1:
The invention makes the separation means dynamic by allowing it to penetrate and remove from the fiber bundle in a repetitive manner during conveyance. The projected parts are positioned to penetrate at specific points along the fiber bundle path, enabling control over the lengths of separation-processed and not-separation-processed sections without requiring complex speed synchronization mechanisms
Data Source
Figure 1
Figure 2
Figure 3(A)~3(B)
AI summary
A partially separated fiber bundle that comprises separation-processed sections and not-separation-processed sections that are alternately formed along the lengthwise direction of a fiber bundle that comprises a plurality of single fibers, wherein the separation-processed sections comprise a plurality of divided fiber bundles that have been divided by separation processing. The partially separated fiber bundle is characterized in that the numbers of single fibers of the divided fiber bundles in the separation-processed section are nonuniform. A production method for the partially separated fiber bundle, a fiber-reinforced resin molding material that uses the partially separated fiber bundle, and a production method for the fiber-reinforced resin molding material that uses the partially separated fiber bundle. Because the partially separated fiber bundle is separated into comparatively thin bundles and comparatively thick bundles that have different numbers of single fibers, when the partially separated fiber bundle has been made into an intermediate substrate that is to be used in composite material molding, it is possible to control thin fiber bundles and thick fiber bundles at an optimal distribution state and to exhibit the flowability during molding and the mechanical properties of a molded article at a good balance.