The Mechanism Design And Analysis For Non-Lubricated Lockstitch Sewing Machine

With the tendency of high speed, high energy efficiency, low costs, intelligent and oil-free for sartorial products, there are more requirements for the control, material and mechanism of the sartorial. However, research of sartorius mechanism in our country is still at the end of lower-level, all of new production don't make theoretical study and performance experimental study, structural parameter of new production don't make optimal calculation but is cut-and-try. Moreover, the technological personnels is less to acquire and apply the modern idea of designing and design method, because they are struggling to fit current production. This article aims to look at the researches of mechanism characteristic, recurs to virtual prototype technique, from the angle of creative design, for reduce new product development, depressed the cost of research.By syncretizing existing mechanism, developing various feasible mechanism, this thesis advances the movement plan of the non-lubricated lockstitch sewing machine, analyzes kinematic characteristics of needle bar mechanism, drawing mechanism, take-up lever mechanism, feed Processing System mechanism respectively, and lays the foundation for simulation analyses on a base of oil lubricating lockstitch sewing machine.And then built up the virtual prototype for the whole mechanism of oil-free lockstitch sewing machine and analyzed parametrically the operating characteristic of thread-taking-up and needle bar mechanism by using the 3-D CAD(Computer-Aided Design) software Pro/Engineer and ADAMS (Automatic Dynamic Analysis of Mechanical Systems).The results provide the basis for trial-manufacture of physical prototyping and betterment design.The sartorius have always been struggling with a problem is reducing vibration. Calculating of dynamic balance is required to the sartorial of high speed. By use the computer simulation, this paper designs a convenient and practical machinery dynamical balancing optimization simulation flows, combined the rationally balancing objective function, it realizes the research of machinery dynamical balancing based on computer simulation, reduces vibration and reaction forces of the system's kinetic pairs, and achieved satisfactory objective.Finally, this thesis uses the modal analysis to the rotating shafts and whole machine by using FEA (Finite Element Analysis) and obtained the correlate relationship between rotate speed and frequency, modal line, produce improvements of components avoid resonance.This thesis analyzes the characteristics of the dynamic of sewing machine successfully through CAE (Computer-Aided Engineering), and draws some practical conclusions. And this provides good reference for mass production, creates favorable experiment condition for control system and software development in the future.