Research On Z-direction Steel Needle Replacement And Fiber Locking Device Of Three-dimensional Fabric

The integrated piercing three-dimensional fabric is a three-dimensional fabric which is uniformly laminated and laid in the plane direction of the carbon fiber cloth,and is vertically stitched by continuous carbon fibers.The fabric has good overall structure and high carbon fiber volume content.It is an excellent substrate for the production of high-performance structural materials and thermal protection materials.At present,it is successfully used in solid rocket engine nozzle,throat insert,combustion chamber,launch vehicle solid booster and so on.Because of the complicated molding process and high technical difficulty of the carbon fiber three-dimensional fabric,the integrated piercing three-dimensional fabric weaving equipment in China is mainly semi-mechanical and semi-automatic equipment,and some are even manually operated.Based on the analysis of the research status of carbon fiber three-dimensional fabric forming equipment at home and abroad,this paper develops a prototype of steel needle replacement and fiber locking device.The main research contents are as follows:According to the traditional steel needle replacement and fiber locking process design,through the program comparison,the device mainly includes Y/Z mobile worktable,needle gripper mechanism,wire feeding mechanism,fiber locking mechanism and tension control mechanism.Due to the detailed design of the determination plan,determining the size of the parts through theoretical analysis,then selecting and checking the parts,and building a virtual prototype using Pro/E software.For the steel needle replacement and fiber locking process,the traditional steel needle gripper can not meet the requirements of clamping the equidistant densely packed Z-direction steel needle,and the special gripper design is carried out.The working process analysis and theoretical analysis of the gripper are carried out.And ANSYS simulation analysis and experimental verification of the work situation.Aiming at the problems of sewing jumping and floating lines in the process of fiber locking,the ideal wire loop shape and forming mechanism in this process are studied based on the principle of chain stitching.The theoretical behavior of steady-state wire loop mechanical behavior analysis of multi-body system is used to determine the ideal formation.The length of the suture required for the wire loop is used to improve the reliability of the stitching.The MATLAB software was used to solve and the Adams software was used to simulation analysis and then carry out experimental research.In the stitching process,the stitch formation is complicated and the bending is more,the yarn is easy to break at the pinhole,calculating the required thread quantity in a single cycle,analyzing the yarn tension,and the discontinuous supply yarn model is established,and the fuzzy PID control algorithm is used to control the yarn tension by using MATLAB software Simulink simulation platform,which provides a theoretical basis for practical work.The control system design and electrical schematic drawing of steel needle replacement and fiber locking device are carried out.According to the assembly drawing and circuit diagram construction,build an experimental platform.Debugging assembled device and weaving of fabrics.