Research On The Relationship Between The Elasticity And Technological Parameters Of High-Elastic Weft-Knitted Fabric

With the improvement of living standards,people's requirements for clothing are not only at the level of beauty,fit and warmth,but also pay more attention to the comfort of clothing.Clothing comfort includes moisture absorption,elasticity,breathability,softness and many other aspects,of which clothing elasticity is an important parameter index for evaluating clothing comfort.There are many parameters that affect the elasticity of clothing,but the parameters that can be flexibly adjusted during the weaving process are mainly two parameters:Feeding speed and Bending depth.The research on the adjustable parameters of weaving can on the one hand quickly estimate the elasticity and pressure range of the forming fabric and judge whether the fabric product is qualified;on the other hand,it can guide the improvement of the production process and provide a theoretical basis for the setting of processing parameters.In this paper,the high-elastic plain-knitted fabric is taken as the research object.The relationship between the fabric elasticity and the weaving technological parameters is analyzed by studying the unidirectional tensile properties of the fabric.Firstly,carrying out the sample trial production and the measurement of sample coil structure.Within the range that the Feeding speed and Bending depth of the loom can be matched,19 sets of sample weaving with different combinations of Feeding speed and Bending depth are completed.The fabric sample was scanned by CT and photographed by VHX-2000 camera to obtain the structure state of the fabric coil,including the course spacing,wale spacing,coil length and other parameters.The change state of the coil and the relative movement trend between the coils were measured.Secondly,carrying out theoretical modeling and analysis.According to the measured fabric loop structure characteristics,a suitable plain-knitted fabric structure model,spring mass model is established.By using this model,the relationship between the elastic coefficient of fabric and the loop structure parameter,course spacing and wale spacing,were calculated and analyzed.The influence of various parameters on fabric elasticity is analyzed theoretically,and the optimal parameter combination configuration under certain elastic conditions is obtained.Lastly,carrying out tensile experiment research and analysis.The measurement and calculation methods of course spacing and wale spacing based on image recognition were studied,a platform for measuring the elastic modulus of yarn was built,and a clamping method was designed to eliminate the effect of curling.On this basis,the relationship between the course spacing and wale spacing,the yarn elastic modulus,and the stress and strain of the sample fabric were measured.The relationship between the course spacing and wale spacing and the fabric elastic coefficient was obtained and compared with the theoretical model.The experimental results agree with the theoretical model.Finally,by analyzing the calculation relationship between the weaving process parameters(Feeding speed and Bending depth)and the fabric coil parameters(course spacing and wale spacing),the correspondence between the fabric elasticity and the weaving process parameters is established.