【作者】 王斐；

【导师】 李小平；

【作者基本信息】 华中科技大学 ， 机械工程， 2021， 硕士

【摘要】 全自动装袋设备广泛应用于饲料、食品和化工行业,高可靠性编织袋立式传送和集成制袋是制袋包装一体化包装机的关键技术。然而,编织袋立式传输过程中容易产生漂移、褶皱,集成制袋过程容易产生折边缝纫阻力等问题。本文针对上述关键技术问题,从立式传输机构设计、大挠度编织袋受力模型、折边阻力分析三个方面展开研究,主要研究内容和结论如下:1)建立了现有编织袋立式传输机构的尺寸约束及模型,分析了编织袋在立式传输过程中存在的法向漂移、段间变形、夹送力不均匀等问题及形成原因,提出了采用开合机构、段间引导钣金、皮带导轨结构等方案来解决上述问题。2)分析得到了编织袋在通过折边器时的阻力是导致编织袋皱褶变形的关键因素,建立了编织袋在拉力和转矩共同作用下的受力模型,求解了编织袋在通过缝包机、折边器过程中多楔带的法向力。3)建立了在斜向载荷作用下,基于椭圆积分的弹性杆大挠度变形模型。分析载荷倾斜角、斜向载荷大小、挠曲线长度、自由端转角、径向位移和法向位移的关系,并求解出了在斜向载荷作用下的挠曲线方程。4)建立了基于椭圆积分的编织袋折边阻力模型,通过MATLAB对模型进行了建模计算,并与Recurdyn中折边受力过程相对比,两者结果较为吻合。得出了双折折边器通过减少半径收缩功能区的长度,可以减小折边阻力的结论,并依据该结论完成了折边器结构的优化工作。更多还原

【Abstract】 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.更多还原