Research On Vertical Transmission And Sewing Method Of Non-coated Woven Bag

Fully automatic bagging equipment is widely used in feed,food and chemical industries.Vertical transmission of woven bag with high-reliability and integrated bag making are the key technologies of packaging machines integrated with bag making.However,woven bags are prone to drift and wrinkles during the vertical transmission,and the integrated bag making process is prone to problems such as folding and sewing resistance.In view of the abovementioned key technical issues,this thesis conducts research from three aspects: vertical transmission mechanism design,large-deflection force model for woven bag,and hemming resistance analysis.The main research contents and conclusions are as follows:1)The size constraint and model of the existing woven bag vertical transmission mechanism are established.The problems of normal drift,deformation between segments and uneven clamping force in the process of vertical transmission of woven bag are analyzed.The methods to solve the above problems are put forward by using the opening and closing mechanism,the guiding sheet metal between segments and the belt guide rail structure.2)The analysis shows that the resistance of the woven bag passing through the folding device is the key factor leading to the wrinkle deformation of the woven bag.The force model of the woven bag under the combined action of tension and torque is established,and the normal force of the multi wedge belt in the process of the woven bag passing through the sewing machine and the folding device is solved.3)A large deflection deformation model of elastic rod under oblique load is established based on elliptic integral.The relationship among load inclination angle,oblique load,deflection curve length,free end angle,radial displacement and normal displacement is analyzed,and the deflection curve equation under oblique load is solved.4)The resistance model of woven bag folding based on elliptic integral is established.The model is calculated by MATLAB,and compared with the force process of folding in Recur Dyn,the results of the two were more consistent.It is concluded that the double-folding device can reduce the folding resistance by reducing the length of the radius contraction function area,and the optimization of the structure of the folding device is completed according to the conclusion.