The Design Of Warp System And Beating-up Mechanism In3-d Weaving Machine

As a composite textile structure preform, the three-dimensional woven fabric has good performance in integrity and profiling. Composites made of it have superior mechanical properties and are used in the aerospace, defense and military industry, transportation, general machinery, construction, energy and other fields. Manufacturing the woven fabrics with three-dimensional interwoven structure has become a modern textile research hotspot. To achieve the mechanized production of three-dimensional woven fabrics, three-dimensional looms with high degrees of efficiency and automation must be developed.The purpose of this thesis is to study the processing technology on three-dimensional weaving and to design the warp system and the beating-up mechanism on three-dimensional loom, which will be discussed in more details in the following.(1) The technology to weave the three-dimensional fabric has been researched, and the weaving technology of the three-dimensional loom has been designed. Great attention has been paid to resolve issues in the adaptability and diversity of three-dimensional looms. On the basis of existing technology, according to the special requirements of weaving three-dimensional fabric, the mechanisms in shedding, weft-insertion, beating-up, let-off and take-up are modified and improved.(2) The principles of the generation of beating-resistance have been researched, and a beating-up resistance calculation method based on the integral calculation which can be applied to both plane fabrics and three-dimensional fabrics has been put forward. It thus lays a theoretical foundation for designing of beating-up mechanism. (3) Two parallel beating-up mechanisms of three-dimensional loom has been designed in this paper. Slider-crank beating-up mechanism has good performance in neutral position, reducing mechanical vibration and accomplishing the beating-up motion; While parallel four link-eccentric wheels beating-up mechanism is simple to carry out.(4) According to the characteristics of the let-off in the three-dimensional weaving process, a let-off system of negative creel has been designed. Considering the fabric variety requirement of the three-dimensional, multiple waip beams have been installed to achieve multilayer warp control in dependently and to control the negative let-off of warp with the aerodynamic damping.(5) An electronic take-up system on three-dimensional fabric has been designed. The take-up motion on three-dimensional fabric has been completed by motor control with Hall sensor. The take-up system comprises two stages:the first stage is a continuous feeding device and the second stage is an intermittent take-up apparatus. For thin three-dimensional fabric, the traditional method can be used for its winding directly; for three-dimensional fabric with high thickness, direct taking-up will destroy the fabric structure so the fabric should be connected to the head-cloth so as to be dragged by the force of head cloth.