Abstract:

Objective In order to address the technological limitations inherent in conventional jacquard leno weaving, a craft historically constrained by low operational speed (100 r/min), rigid pattern design frameworks, and mechanical incompatibilities with modern production demands, the research targets two critical challenges. One is the tension imbalance between standard ends and doup ends caused by conventional heald configurations, which restricts weaving speed and pattern complexity, and the other is the labor-intensive manual pattern design process that hinders customization capabilities. By reengineering the lifting heald mechanism and developing a matrix-based digital design system, this work bridges the gap between artisanal textile heritage and industry requirements. The elimination of standard heald devices and implementation of a dual warp stop-motion device system represents fundamental mechanical breakthroughs, enabling simultaneous preservation of traditional aesthetics and achievement of industrial-scale productivity.

Method The methodology integrated mechanical innovation with mathematical modeling. A redesigned doup heald device replaced conventional standard shaft using a pressing rod to position doup threads beneath standard threads, reducing heald usage by 50%. A dual warp stop-motion system created three distinct shed types: crossed, open, and plain. Matrix operations (A₁=A₂×A₃) were applied to model fabric structure (A₁), heald arrangement (A₂), and pattern files (A₃), enabling digital pattern generation. Practical validation involved weaving trials with 1∶3 twisted/ground warp ratio using single-layer and triple-weft structures on a 4,800-needle electronic jacquard loom.

Results The comprehensive trials revealed transformative advancements across technical and operational parameters. The redesigned crossed heald mechanism enabled a 120% increase in loom speed, improving operational capacity from 100 r/min to 220 r/min while maintaining continuous stability, with warp tension differentials between standard and crossed warp systems. Matrix-based pattern generation demonstrated exceptional precision, achieving consistency with manual designs for complex 8-end/3-steps weft-faced satin structures, while resolving structural conflicts in asymmetric warp distributions through matrix regularization techniques. Digital methods reduced trial weaving iterations, compressing pattern development cycles for multi-layer fabrics, with computational efficiency improvements allowing simultaneous optimization of six critical parameters (thickness of yarn, weaving speed, warp tension, warp density, pick density, heald lift height, etc.) through matrix parameterization. Structural versatility was evidenced by the system's ability to produce both conventional crossed leno fabric (requiring synchronized 2-axis coordination) and simplified non-crossed variants, the former achieving faster processing through fixed back heald positions. Practical validation across two fabric structures, i.e. single-layer and triple-weft structures, confirmed pattern fidelity on multiple high-speed rapier jacquard loom. The technology demonstrated industrial scalability. In comparative trials, the system enabled seamless integration of leno patterns with conventional jacquard weaves.

Conclusion This research provides a detailed analysis of the characteristics of the structure of the leno Jacquard loom for leno jacquard weaving and establishes a groundbreaking digital-physical framework that redefines leno jacquard production for the smart manufacturing era. It introduces a comprehensive process innovation design for the plastic Jacquard harness, which is most compatible with digital jacquard machines and high-speed rapier looms. The design innovatively modifies the crossing warp device by directly connecting the crossing warp to the warp beam, eliminating the need for the back hook. By adding drop wire device of crossing warp devices of various sizes and utilizing the function of the pressing rod device, it innovatively creates a unique dual-opening structure with open and crossed sheds, as well as a long-distance single-opening structure with a standard shed opening. Additionally, the article innovatively draws the template of weaving draft of leno jacquard fabric for both the crossing warp and non-crossing parts of the leno weaving fabric, deeply analyzing the mathematical relationships among the pattern, heald threading, and pattern card diagrams in these diagrams. It verifies the generation methods and rules of the weaving file through various changes in organizational structures, it tests the digital innovative design theory of leno jacquard weaving fabrics, ultimately achieving industrialization.

Key words: leno jacquard fabric, crossing warp device, double opening structure, digital design, fabric design