Research On Auotomatic Weaving Of Variable Width Fabric

With increasing demands fabric uses,fabrics with constant width could not meet customer requirements.In the case of the clinical use of artificial blood vessels,a tapered tube fabric has to be woven to better simulate the shape and performance of blood vessels in the human body.At present,there are two kinds of weaving methods to realize the change of fabric width:one is to increase or decrease the number of warp yarns on both sides of the width direction;the other is to change the weft density,but automatic weaving is not currently implemented.Based on weaving tapered tubular fabrics,the research studied the influence of the lifting and lowering the chest beam on the weaving process.Also,the loom was modified to facilitate automatic weaving of variable width fabrics.Firstly,the effect of the lifting and lowering the chest beam on the weaving was studied.The study established geometric relationships and obtained that changing take-up quantities could compensate weft density deviation,adjusting the rear beam height could eliminate uneven tension warp yarns,controlling the position of rapier and shuttle box could enable the rapier to normally enter the shed and enable the shuttle to normally enter the shuttle box.The numerical relationships between the chest beam relatively with the rear beam,the rapier and the shuttle box were conducted,providing a foundation for automatic weaving of variable width fabrics.Secondly,the specific tubular fabric weaving loom was modified.An electric cylinder with high precision and stable running performance was used to control the rise and fall of chest beam,rear beam,rapier and shuttle box.The software of the loom was refined according to the theory of equal tightness design and the conducted numerical relationships between chest beam relatively with rear beam,rapier and shuttle box.The software could use to calculate the variable width fabric parameters and the lift parameters of the electric cylinder.Next,the modified loom was debugged.The single-step moving method was implemented to verify the accuracy of each mechanism and the rationality of software design,and the deficiencies of the loom and software were improved.Finally,taking the tapered tubular fabric as an example,the reasonable parameters ofweaving were designed,and the tapered tubular fabrics were automatically woven and analyzed after weaving.The problems occurred in the weaving process were solved.Tests of the off-loom fabrics mainly included fabric width,cone length,fabric warp and weft density.Results showed that tested values of the woven fabrics were as the same as the designed parameter values,which indicated the loom design was rational and could achieve automatic weaving of variable width fabrics.