Optimization Design Of The Opening Mechanism Of A Three-dimensional Loom With Hollow Fabrics Connected By Flanne

Compared with traditional metal and alloy materials,composites have been widely used in transportation,aerospace,civil industry,national defense and military industry because of their high specific strength,large specific modulus,high temperature resistance,corrosion resistance and good design.As a preform of composite materials,the three-dimensional hollow fabric is woven with a three-dimensional loom.Because the flannelette of the middle connecting layer connects the upper and lower layers together to form an overall three-dimensional hollow structure,the fabric has certain compression elasticity,and there is sufficient gap between the upper and lower layers.Compared with other laminated three-dimensional fabrics,angle interlocking three-dimensional fabrics and other solid three-dimensional fabrics,three-dimensional hollow fabrics can not only eliminate the disadvantages of low interlaminar strength and vulnerable to impact damage of laminated structural composites,but also have the advantages of air permeability,sound absorption and light texture.Therefore,the fabric is mainly used in lightweight plates,insulation and heat insulation materials,noise shielding materials,etc.This paper mainly takes X-type hollow woven fabric as the research object,introduces its fabric structure and weaving principle,and focuses on the design and optimization of loom opening mechanism.The main contents are as follows:(1)The structural characteristics of three-dimensional hollow woven fabric are introduced.According to the structural form of X-type hollow woven fabric,the weaving process and weaving technology of X-type middle space spacer fabric are analyzed and studied.The weaving principle of X-type spacer fabric is designed in detail.The three-dimensional model of the whole machine is designed.(2)The detailed structure analysis and design of let off,beating up,weft insertion and tension compensation are carried out,and the three-dimensional structure is designed in Solid Works.The timing coordination and design of the main mechanism of three-dimensional loom are carried out.(3)In view of the fact that the existing opening mechanism of hollow fabric three-dimensional loom can not fully meet the requirements of frequent transformation of large spacing hollow fabric structure,large opening stroke and large heald lifting force,a set of servo motor opening mechanism is designed.The mathematical model of driving arm angle and heald frame displacement of electronic opening mechanism is established.The pressure angle of swing arm is compared and simulated in MATLAB to obtain the optimal swing arm angle.(4)In view of the fact that the existing opening mechanism of hollow fabric three-dimensional loom can not fully meet the requirements of frequent transformation of large spacing hollow fabric structure,large opening stroke and large heald lifting force,a set of servo motor opening mechanism is designed.The mathematical model of driving arm angle and heald frame displacement of electronic opening mechanism is established.The pressure angle of swing arm is compared and simulated in MATLAB to obtain the optimal swing arm angle.