Research On Warp Knitting Jacquard Technology And Its Product Process

The warp knitted jacquard fabric has the characteristics of high production efficiency,rich pattern,and variable layers.Its jacquard bar is different from other warp-knitted bars.Each jacquard bar can be offset independently,and can control the deviation of jacquard bar in front and back of the needle,which can better meet people's design requirements for the diversity of pattern.However,whether in the new three-needle or four-needle technology of Jacquard,due to the fact that Jacquard has only two offset position,the jacquard stitch produced by its lateral movement is still limited.At the same time,the complexity of jacquard patterns brings a lot of difficulties to artificial design.The application of computer-aided design is not only very helpful to pattern design,but also can shorten the process flow.However,the existing simulation models still have many shortcomings in the simulation of warp knitted jacquard fabric.Aiming at the problem that the existing jacquard stitch pattern is insufficient and the simulation model needs to be improved,this paper improves the jacquard component and analyzes its principle and the formation of the stitch.In addition,a new three-dimensional loop model is proposed.The methods and specific research are as follows:First of all,in view of the limitations of Jacquard stitch,this paper analyzes the offset principle of piezoelectric Jacquard with two offset positions,and proposes to obtain a new piezoelectric jacquard with three offset positions by adding a baffle mechanism.Then analysis of the needle selection technology,the principle of jacquard patterning and the technology of the three-station jacquard.After the same floating stitch structure and the triple loop stitch,which is not conducive to weaving are discarded,and compared with the 16 ways of padding of three-needle and four-needle technology of the two-station jacquard,the three-station jacquard still has 36 laying methods,which provides a theoretical basis for the design of the jacquard weave pattern.Secondly,the characteristics of the three-station jacquard stitch-units are analyzed.According to the decorative pattern,the stitches are divided into four categories: thick stitch,thin stitch,floating stitch,and mesh stitch.And further according to the number of crossing needles,36 types of stitches are divided into extra thick stitches,left open thick stitches,right open thick stitches,left thin stitches,middle thin stitches,right thin stitches,up floating stitches,floating stitches,double floating stitches and mesh stitches.Then the formation principle,lay-up method and formation effect of these jacquard stitch-units are detailed analyzed,and the decorative pattern of some special stitches are explored.Then,through the mechanical analysis of the loop,a new three-dimensional loop model that based on VC++ is proposed.The mathematical description of the laying digital,the connection method of coordinates and the three-dimensional coordinate formula are explored,and a new loop model is established which is subject to force offset.OPENGL functions are used to process the shape,color,light and shadow of the model to achieve three-dimensional,and the functions of zoom and rotation are added to facilitate observation.When the formula of laying digital and parameters is given,the simulation diagram can be drawn,which provides the basis for the application design of three position jacquard.Finally,the design process of warp knitted fabrics is analyzed.Including the selection of raw materials,process flow,process design,etc.And analyzing the application of three-station jacquard which can be regard as the bottom net stitches and the main pattern stitches.This research provides a reference for the design and simulation of new warp knitting technology and three-station jacquard technology.Hoping to promote the development of warp knitted jacquard fabric.