Research On Precision Forming And The Key Technology Of The Die For Auto Transmission Conjunction Gear

Conjunction gear is also called the helical transmission gear with clutch gear,It’s oftenused for transmission and shift design of automobile gearbox.At present,most of the autotransmission conjunction gear were produced by pressing the gear body and spline toothcircle together after cutting processing separate or welding them together after themachining processing respectively in our country.Although this process can satisfy user’sbasic requirements,this method is not only lower efficiency and higher cost,and alsosometimes they are even unable to be processed because of the limits of the structure.Itcaused a certain gap between the manufacture of the products and the original designthought.The conjunction gear is difficult to machine by forging technology is that designerdesigned a small-angle in the back taper part of gear in order to prevent the meshing fromdislocating in the course of gear shift.The traditional forging process can neither form thetooth nor make mold release normally.Therefore,in view of the difficulties,the paper putsforward a new processing method that forms tooth preliminarily through warm forming theconjunction gear blank,and on this basis,cold finishing the tooth shape.The paper put forward many different kinds of solutions about the processing ofconjunction gear’s warm forging forming.The finite element numerical simulation softwareDEFORM-3D simulate numerically many of the scheme in various processes byestablishing three dimension finite element model.And then,analyse the simulated data bycomparing the changes of the simulation results include the equivalent stress,equivalentstrain,forming load and mold wear and so on,so as to achieve the effect that optimization ofconjunction gear forging processing and providing the theory basis and guidance for theoptimize mould design.By simulating and analysising the data that tooth high and tooth thickness ofconjunction gear in the finishing process of tooth,we can get the surplus of tooth high andtooth thickness in the best finishing processing.And in the light of the special pour taperedgear tooth shape structure of conjunction gear,we put forward a method that radialextrusion over the cone forming,and on that base design a mold scheme and two teethmode structure.we select the best scheme by simulating and comparing the analysis of theprocessing of the reversed cone tooth’s forming and checking the strength of two teeth dies,The mould’s structure of the scheme is more reasonable,more easily control,moreconducivly prolong its life.The process scheme expounded in the paper not only overcames many shortcomingsof manufacturing techniques of conjunction gear,but also explores a series of problems anddifficulties that our country faced about whole precision forging of conjunction gear.At thesame time,the paper analyse and optimize some key problems,especially solve theproblems that conjunction gear’s reversed cone tooth shape can’t be formed and can’t bereleased.Based on the simulated result,design the best process of the conjunction gearforming and die structure and verifying the simulation results by the practical productionsituation,the results show that the product meets the requirement.