Structural Optimization Design Of Yarn Carrier For Three-dimensional Braiding Machine

Three-dimensional braided composite material is a new composite material,which is widely used in military,aerospace,civil and medical fields due to its unique characteristics.The use of three-dimensional braided preforms to enhance the composite material,because of its multi-directional fiber orientation,three-dimensional weaving and other characteristics,making the composite mechanical properties of the composite to better play,so a lot of scientific research workers attention.At present,for this kind of three-dimensional braided composite material,one of the bottlenecks in the fabrication of the variable-section and variable-diameter prefabricate is limited to its application in actual production.In the existing three-dimensional weaving equipment,the more prominent problem is that the weaving equipment can't be automated,requires a large number of artificial auxiliary weaving,which not only reduces the efficiency while increasing the labor costs,in view of this,for the active study of 3D woven with yarn has obvious significance.In this paper,a yarn feeder that can automatically add and subtract yarns is developed by using the matured yarn adding and subtracting technology combined with the current technology of adding and subtracting yarns so as to complete the weaving work of the preform accurately and efficiently.Based on the three-dimensional weaving technology,this paper discusses the knitting method to realize the variable-diameter preform.According to the comparative analysis of different weaving technologies,the design scheme of the active yarn feeder that can increase or decrease the yarn is proposed.A plurality of yarns,through the chemical bonding method to complete the process of yarn increase,and then change the number of braided yarn bundles,in order to achieve this variable cross-section and the purpose of reducing the fabric weave.In this paper,the structure design and assembly of the parts of the yarn carrier are completed based on the Creo software platform.The active yarn carrying device mainly includes the yarn storage,the addition and the decrease of the yarn.The relevant parts of the software are used to assemble the designed parts in a virtual manner to verify whether there is any interference between the parts,thus laying a theoretical foundation for the subsequent processing and assembling of the prototype of the yarn feeder.In response to the automatic yarn feeder to increase or decrease yarn work requirements,this paper discusses the selection of chemical adhesives and their characteristics compared with the reliability of chemical bonding were calculated and analyzed,which including the calculation and inspection of the bonding effect of the main and secondary yarns and the analysis and verification of the strength of the yarn increasing device,and the design of yarn feeder is met to meet the design requirements,thus laying a solid foundation for the subsequent design work.At the end of thesis,ANSYS is used to statically analyze the important parts in the yarn-adding and removing device,verify the reliability of the work and optimize its parameters to obtain more reasonable data,so the conditions for the processing and analysis are prepared.