Research Of Automatic Assembly System Thread Connection

Screw joint assembly is more and more important in the industrial assembly manufacture and one of the main methods of finishing the sophisticated screw joint is to study and enhance the core technology. This dissertation studies and designs the system of multiple unit valve screw joint assembly combined with the enterprises’ demands under the background of the project application of screw joint assembly in the production of multiple unit valve assembly. The article has mainly finished these studies as follows:(1) Give a brief introduction on the background and source of the research project. This article analyzes the development process and the status quo of the study, points out the significance of the equipment tightening screw thread to the guarantee of the multiple unit valve screw assembly’s quality and efficiency, and dissects the main target and the contents of work of this project research very carefully.(2) The design of screw joint assembly system consisted of automatic tightening equipment, multiple unit valve preliminary assembly elevating platform and electric-controlled cabinet, which is based on the enterprises’actual demands. The lectotype and job description have also been finished.(3) This article determines the numerical value of bolts’tightening angle in the elastic range, proposes the control method about screw-tightening based on torque-angle control method and designs the workflow of tightening control for the mathematical model, including preload, tightening angle and tightening torque, in the process of screw assembly tightening.(4) For a particular type of screw thread connection of pre-tightening torque requirements, tighten the shaft unit control model is established, the design of the process of the screw thread connection expected trajectory, speed control model is established for simulation, it is concluded that with model compensation PI pole assignment control strategy can achieve better dynamic response and steady-state accuracy.(5) Build dSPACE DS1103 control of servo motor speed adjusting experiment system to control the simulation of screw thread connection, the parameter estimation and servo motor speed control algorithm validation.