Fiber Bundle Joint with Segmented Interlacing for Carbon Fiber Production
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for joining precursor fiber bundles in carbon fiber production lead to heat accumulation and breakage in the fiber joint portion during the calcination step, resulting in reduced productivity and potential thermal destruction.
Innovation Solution
A fiber bundle with a fiber joint portion comprising superposed and interlaced fiber portions, where the fibers are interlaced at intervals in the length direction and unraveled in between, allowing for efficient heat dissipation and maintaining fiber density, preventing breakage and slippage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If pressurized fluid jets are applied to interlace the fibers in the fiber joint portion, then the fiber bundles can be joined together, but the fiber density becomes too high causing heat accumulation and thermal destruction during the oxidizing step
Solution Approach 1:
The fiber joint portion is divided into multiple interlaced sub-portions (first, second, and third sub-portions) along the length direction, with unraveled fiber portions between them. This segmentation reduces the fiber density in any single location, preventing heat accumulation while maintaining overall binding strength through distributed interlacing points.
2Reliability
If the temperature of the oxidizing step is lowered to prevent heat accumulation, then thermal destruction is avoided, but the oxidizing step requires significantly longer time, decreasing productivity
Solution Approach 1:
By segmenting the fiber joint portion into multiple interlaced sub-portions with unraveled sections between them, the invention reduces local fiber density and heat accumulation. This allows the oxidizing step to proceed at normal temperatures without thermal destruction, maintaining high productivity while ensuring reliability.
3Strength
If pressurized fluid jets are applied to large-number filament fiber bundles, then the bundles can be joined, but the jets cannot cover the entire bundle, resulting in uneven interlacement and local density increase that accelerates heat accumulation
Solution Approach 1:
The invention segments the fiber joint portion into multiple interlaced sub-portions distributed along the length direction. This segmentation ensures that even for large-number filament bundles, the pressurized fluid jets can effectively cover each sub-portion without creating excessive local density, thereby preventing accelerated heat accumulation while achieving sufficient interlacement.
Solution Approach 2:
The invention creates different structural zones along the fiber joint portion: interlaced sub-portions where fibers are bound together and unraveled fiber portions where fibers are separated. This local quality variation ensures adequate interlacement for strength while preventing excessive density and heat accumulation in any single location.
4Strength
If the fiber joint portion has high fiber density to ensure binding strength, then the bundles are well joined, but heat accumulation occurs causing breakage during the oxidizing step
Solution Approach 1:
The fiber joint portion is segmented into multiple interlaced sub-portions (first, second, third sub-portions) separated by unraveled fiber portions. This segmentation distributes the binding strength across multiple locations while reducing the fiber density in any single location, thereby preventing heat accumulation-induced breakage during the oxidizing step.
Solution Approach 2:
The invention implements local quality variation along the fiber joint portion, creating alternating zones of interlaced fibers (for strength) and unraveled fibers (for heat dissipation). This allows the structure to simultaneously achieve adequate binding strength and resistance to heat accumulation.
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 enables continuous production of carbon fibers without significant temperature reduction, maintaining high operating efficiency and preventing heat accumulation, thus improving productivity and preventing fiber bundle breakage.
Implementation Method 1
applying pressurized fluid jets emitted from jetting nozzles to interlace the fibers
Implementation Method 2
an unraveled fiber portion in which said fibers are unraveled and that is located between said two or more interlaced fiber portions
Data Source
Figure 1~4
Figure 5~7
Figure 8~11
AI summary
A fiber bundle which has a pieced part formed by jetting a pressurized fluid against a fiber-bundle overlap formed either by directly superposing the ending part of a fiber bundle composed of many fibers on the beginning part of another fiber bundle composed of many fibers or by superposing the end part and the beginning part on a jointing fiber bundle composed of many fibers, whereby the many fibers of the fiber bundles are interlaced with one another to thereby piece up the fiber bundles. The pieced part comprises an opened-fiber part in which the fibers have been opened and interlaced-fiber parts respectively located on both sides thereof, each interlaced-fiber part being composed of a plurality of constituent interlaced parts located apart in the width direction for the fiber bundle. The fiber bundle having the pieced part, when fed to a process for producing a carbon fiber, is inhibited from suffering thermal damage to the pieced part, because the pieced part comprises the opened-fiber part and the interlaced-fiber parts.