Research And Design Of Portable Numerical Control Torque Wrench Controller

Electric tools can expand the scope and enhance the strength of human action,and greatly improve the work efficiency.They play very important roles in daily work and life.With the increasing mechanization and automation of social production,electric wrench has been widely used in many industries to strengthen and tighten bolts.The current domestic electric wrench has gradually become incapable of meeting people's increasing use demands.This thesis presents the design of an advanced electric wrench and studies its portability,reliability and torque accuracy.In line with the basic principle of saving resources and costs,this portable CNC fixed torque wrench can accurately control the output torque,effectively control the forward and reverse rotation,and can retrieve previous working conditions of the wrench.Furthermore,the whole drive system is set up to protect the module and increase operation safety.This thesis studies and develops the control system of the portable CNC fixed torque wrench.It expounds the background and significance of this subject,briefly analyzes the current development of electric wrenches at home and abroad,and the necessity of electric wrench design.The theoretical basis and control model for the design of electric wrench controller are described in this paper.At the same time,the design requirements of dc motor driven by the mathematical model are proposed.This thesis introduces the hardware circuit design of the portable CNC fixed torque wrench.The hardware circuit includes system main controller circuit,motor drive circuit,current detection circuit,power supply circuit,liquid crystal display and key control circuit and system protection circuit.The functions and principles of each circuit module are described respectively.This thesis introduces the software design of wrench controller system based on hardware.The overall process of system software design is described.The process of motor driver,data acquisition program,liquid crystal display program flow,key processing program flow and data storage procedure are program respectively.And the communication interface of upper computer based on C#is briefly introduced.The NC set torque wrench is assembled and debugged to test prototype,and the torque test platform built by the commissioned manufacturer is tested repeatedly to obtain a large amount of data.Through the data analysis and the result verification,I have designed the method allowing the user to preform adjustment for in-situ calibration,and achieved the wrench design requirements of torque output range of 800-3200N·m with error less than 3%.The final design has validated and accepted by,the manufacturer and has now entered production.