The Research On Engagement Principle And Transmission Performance Of Double Roller Worm Pair

Traditional double enveloping worm gear with planar generating surface has the characteristics of strong bearing capacity,high transmission efficiency and long service life,but at the contact point of the tooth flank,the relative sliding speed is high with serious agglutination and abrasion.The author studies a new meshing type and theory in order to reduce the friction and improve the efficiency.In this paper,double-cylinder enveloping worm pair adopts planar enveloping gear surface and uses double-cylinder roller so that the public section of two Cylindrical rollers replacing enveloping master plane together with the worm forms "mismatching" meshing transmission.In this type of transmission,the instantaneous line contact transforms into instantaneous point contact where most sliding friction translates into rolling friction and Meshing efficiency is greatly improved.According to this mismatch meshing idea,the load distribution,relative velocity and meshing efficiency of the transmission are analyzed and studied in this paper.Firstly,based on the space meshing theory,the basic meshing theory system of double roller toroidal worm pair is established,the meshing equations of worm and tool worm gear are deduced,and the numerical calculation function of MATLAB and the three-dimensional modeling ability of Pro/E are used.The solid model of worm and worm wheel is established,and the assembly of double roller worm gear pair is completed.Secondly,according to the force characteristics of worm gear teeth,the relative velocity at the contact point between the meshing surfaces is deduced.By using MATLAB software,the variation law of relative velocity at contact point during the whole meshing process of worm and worm is obtained.The results show that the rotation speed of the roller greatly reduces the relative sliding speed at the contact point between the meshing teeth.Finally,the expression of meshing efficiency of worm pair is deduced,and the variation law of meshing efficiency of worm pair in the whole meshing process is obtained by using MATLAB software.The influence of envelope mother plane inclination,roller and friction coefficient on meshing efficiency of worm pair is analyzed systematically.The method and theory of further improving the meshing efficiency of worm pair are put forward.