Peirce机织物几何结构模型的探讨

织物几何结构就是纱线在织物内部的屈曲状态,它影响织物的外观效应和物理机械性能,必须精确计算.在被普遍使用的Peirce机织物几何结构模型中,暗含如下假设:1织物中经纬纱屈曲波高无论怎样变化,其和均等于经纬纱理论直径之和乘以压扁系数;2同一浮长覆盖下的纱线中心在同一水平面上,屈曲波高仅与织物密度和织造缩率有关.从两个方面对此进行验证,一是以经典教材多块织物样品为例,用Peirce公式计算结果评估自身的精确性;二是用Nedgraphics纹织系统设计同一经纬密度的各种结构的机织物,在电子提花机上织造后利用Keyence 3D共聚焦显微镜对织物正反面进行非破坏性测量,得到不同浮长织物的屈曲波高并进行分析.结果表明,Peirce机织物的几何结构模型存在不足,需进一步改进.

Study on Peirce woven fabric geometry model

The geometry structure of the fabric is the buckling statue in the weave, which influences the appearance effect and physical and mechanical properties. Thus, the geometry structure has to be calculated delicately. Peirce gave the woven fabric geometry model under the assumptions： （1）no matter how the yam crimp wave height changes, it is equal to the sum of the diameter of the warp and weft yams ; （2）under the same float, yarn centers are on the same horizontal plane, the crimp of the yam is only related to the shrinkage and fabric density and weaving. In this paper, two methods are used to evaluate the model. （ 1 ） Some examples of the woven fabrics listed in the classic books are cited and recalculated according to the model; （2） Some special samples with different woven structure are designed based on Nedgraphics Jacquard CAD System, woven on Tongyuan loom and measured by Keyence 3D Laser Microscope. All the results demonstrate that the calculation based on Peirce model are not accurate enough. It is necessary to revise the geometry model for the woven structure.