摘要
文章针对以往凸轮开口的形式限制和性能缺陷,在结构创新、理论分析和实验验证基础上,设计开发了一种采用双轴驱动的积极式共轭凸轮开口系统。利用Matlab构建基于余弦加速运动规律的凸轮理论廓线,通过三维CAD建模和虚拟装配建立功能型数字样机。Motion仿真结果显示:开口运行状态与凸轮理论廓线分段特征相匹配,摆杆和综框的运动学曲线符合余弦加速运动规律设计预期。不同转速下的比例模型测试实验表明:在凸轮提综和回综过程中,综框升降平稳、机构运行可靠,且纱线形变和梭口特征明显,具有良好的开口工作效能。验证了设计方案的理论正确性与实践可行性,为织机凸轮开口系统的设计创新提供了有力借鉴。
Conjugate cam shedding mechanism is a common form in modern high-speed looms.It is different from the negative cam shedding in that no heald returning device is needed on the conjugate cam shedding which has the characteristics of high transmission accuracy and small vibration impact.The traditional conjugate cam shedding is mostly arranged coaxially;therefore,multiple pairs of main and auxiliary cams need to be installed on the same transmission shaft at the same time,which limits the axial size of cam and rotor to a great extent.When the contact width between the cam and the rotor is too small,it is easy to cause large extrusion stress on the contact surface,which is not conducive to reducing cam wear and prolonging working life.In order to improve the bearing conditions of conjugate cam shedding system,a new external conjugate cam shedding system with double shaft transmission is developed through structural innovation,mechanical design,program compilation,dynamic simulation and experimental verification.Based on the reference of coaxial conjugate cam shedding system,a shedding mechanism driven by double shaft was established through structural analysis and equivalent transformation.The cosine acceleration motion law was applied to the motion of heald frame,and the design program of cam theoretical profile was developed by using Matlab software,and then the dynamic calculation and analysis of cam pressure angle were realized.The two-dimensional coordinates(x,y)of the theoretical profile were transformed into three-dimensional coordinates(x,y,z)through data interface program,and the three-dimensional CAD geometric model of the cam and rotor was respectively set up by SolidWorks.On the basis of that,a functional prototype simulation model of the conjugate cam shedding driven by double shaft was constructed in the form of planar links and gear transmission,and the kinematics simulation analysis of key load-bearing components such as swing link and heald frame was carried out.On the basis of proportional model,the experimental tests of heald frame rises and falls at different speeds were used to verify the feasibility of design scheme and working principle of the mechanism.Through actively controlling the lifting movement of heald frame in the form of double cam locking,the axial size of cam could be doubled compared with coaxial conjugate cam,which was helpful to improve working performance and bearing conditions of conjugate cam shedding system.The simulation and experimental results show that the cam shedding system has good working performance,and design scheme and principle can meet the requirements of mechanism design conditions and plain fabric weaving process,and it can effectively reduce the extrusion stress and wear between cam and rotor.The application of double shaft drive in the transformation of conjugate camshedding system can not only solve the problem of contact wear between cam and rotor,but also help to improve the working efficiency of cam shedding system,which will provide important support for the innovative design and high-speed development of shedding system on modern loom.
作者
邱海飞
陈铭
QIU Haifei;CHEN Ming(School of Mechanical Engineering,Xijing University,Xi’an 710123,China)
出处
《丝绸》
CAS
CSCD
北大核心
2022年第6期66-71,共6页
Journal of Silk
基金
陕西省教育厅科研计划资助项目(15JK2177)
西京学院高层次人才专项基金资助项目(XJ20B09)
西京学院横向课题资助项目(2019610002001915)。
