Theoretical And Experimental Study On Axial Rolling Forming Of Worm

Worm is a kind of parts widely used in transmission systems.The main processing methods currently include turning,milling and grinding.Cold rolling processing technology has the characteristics of high forming efficiency,no material waste,high fatigue strength of formed parts,and low cost.In recent years,worm cold rolling has become a research hotspot in the worm machining industry.This paper takes copper worm cold-rolling forming as the object,studies the basic theories such as the tooth profile design of the rolling wheel,the bite conditions of the rolling process,the eccentric bending of the workpiece,and conducts an experimental study on the quality of copper worm rolling.The main research contents of this paper are as follows:(1)The normal tooth profile design of the rolling wheel and the strength check of the tooth root of the rolling wheel are studied.Based on the principle of spatial helical gear meshing,the normal tooth profile of the rolling wheel is derived from the worm tooth profile;the finite element model copper worm rolling simulation is carried out,and the force energy parameters in the simulation are used for the tooth root strength of the rolling wheel Check.(2)The bite conditions of the worm axial cold rolling are pushed and the finite element simulation is carried out.According to the basic size and relative position relationship between the workpiece and the rolling wheel,the biting conditions of the workpiece are deduced,and the influence of friction coefficient,spindle inclination angle,rolling wheel entry angle,rolling wheel outer diameter and blank diameter on biting conditions is analyzed.(3)The eccentric bending phenomenon and the cause of the workpiece in the cutting-in stage of worm rolling are studied.The mechanism of eccentric bending of the workpiece is analyzed,and the influence of the yield strength of the workpiece material,the diameter of the workpiece,the elongation of the workpiece,the length of the support sleeve,the gap between the support sleeve and the workpiece,and the rolling force on the eccentric bending of the workpiece are studied.(4)The experimental research on the factors affecting the rolling stability and forming accuracy of the worm is carried out.The influence of the cutting angle and length of the cutting section of the rolling wheel on the rolling stability is analyzed through experiments,and the influence of the rolling speed and the inclination of the spindle on the forming accuracy is studied.The research methods and research results in this paper provide theoretical support and good practical value for the design of the axial cold rolling die,the selection of process parameters,the feasibility and stability analysis of rolling processing of the worm.