Jointed Strand Structure for Clean Cutting and Fiber Dispersity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for jointing carbon or glass fiber strands result in uneven bundle widths, increased monofilament count, and reduced cutability, leading to defects and mechanical property deterioration in chopped strand mats.
Innovation Solution
A method involving superposing strands with oriented fibers, creating slits orthogonal to the fiber direction, and interlacing monofilaments at joint spots to form a joint portion with slits, enhancing flexibility and reducing monofilament interlace.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If strands are jointed by making a knot, then strands can be connected, but the knot may remain in the product causing defects, or the strand may break during cutting
Solution Approach 1:
The joint portion is segmented into multiple small joint spots rather than one large knot. The air splicer creates multiple localized interlacing points along the strand joint area, distributing the connection function across several segments. This segmentation prevents formation of a single large knot that would cause defects, while maintaining reliable strand connection through cumulative effect of multiple small joint spots.
2Strength
If strands are jointed by twisting, then joint strength is improved, but chopped strands may not be cut properly and areal weight unevenness occurs
Solution Approach 1:
The air splicer applies localized interlacing action at specific joint spots rather than uniform twisting along the entire joint portion. This creates local quality variation where only specific points have increased monofilament interlace for strength, while surrounding areas maintain normal cutability. The localized treatment prevents widespread impact on chopping uniformity and areal weight distribution.
3Reliability
If air splicer is used to interlace monofilaments, then strands can be connected, but the number of monofilaments at joint portion increases causing poor cutability and large chopped strand lumps
Solution Approach 1:
The air splicer applies partial interlacing action only at specific joint spots rather than uniformly across the entire joint portion. This partial action creates sufficient connection reliability at critical points while avoiding excessive monofilament accumulation that would deteriorate cutability. The controlled, localized application of interlacing force prevents formation of large chopped strand lumps.
4Manufacturing precision
If multiple strands are twisted together, then chopped strands with large number of monofilaments are reduced, but areal weight unevenness is improved only partially
Solution Approach 1:
The patent replaces the mechanical twisting system with an air splicing system that uses compressed air to create localized interlacing. This substitution eliminates the need for complex mechanical twisting mechanisms while achieving similar or better control over monofilament distribution. The air-based system provides more precise control over joint spot formation, leading to improved areal weight uniformity without increasing device complexity.
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
Improves cutability and dispersity of chopped strands, reduces bundle width unevenness, and maintains mechanical properties by minimizing monofilament interlace and slit presence.
Implementation Method 1
a joint portion in which the first strand end and the second strand end are jointed by interlacing monofilaments using an air splicer
Data Source
Figure 1
Figure 2
Figure 3(a)~3(d)
AI summary
In order to provide a jointed strand which exhibits excellent cutability in a case of forming a chopped strand, exhibits excellent dispersity after cutting, and can control a bundle width of the chopped strand, the jointed strand includes a superposed portion in which a first strand end in which fibers are oriented in one direction and a second strand end in which fibers are oriented in one direction are superposed; and a joint portion in which fibers of the first strand and the second strand are interlaced at the superposed portion, wherein the joint portion has a slit extending in a fiber orientation direction and a joint spot adjacent to the slit at one location or a plurality of locations aligned in a direction orthogonal to the fiber orientation direction, and monofilaments of the first strand and the second strand are interlaced at the joint spot.