Analysis And Optimal Design For Synchromesh Behaviour

This paper deals with the synchromesh behaviour of the manual car gearbox.Firstly, the gear-changing process, as well as problems of behaviour using theBorg-Warner type synchroniser is studied and eight main operating phases are defined.The phases are described using classical tribological, mechanics, and thermodynamicstheories. Mathematical models of phenomena which can be used for description of thebehaviour are collected or innovative presented. And all this models are interconnectedto describe synchronizer behaviour and included in a numerical simulation software.Measured data on synchronizer test rig are compared with the results of simulationsoftware. The importance of the dynamical behaviour of the synchronizer is highlightedby simulations.Then, double bump phenomenon and stick-slip phenomenon during gear changingis emphatic studied. Double bump, key phenomenon for the feel of gear changing isassumed to be the maximum axial operating force coming from short successive phasesat the end of the gear-changing process. And more works are done to define its effectsfactors one by one. Stick-slip is supposed to be present in two contact zones: sleevesplines and the synchronizer cone. The effects in both zones are discussed. Stick-slip isseemed as a main component of the internal excitation, and the moment of the end ofthe indexing phase is determined by it.Further, improvements of practical use is premited to suggest according todiscussion of the results，which including the number of grooves, the angle of claws andsome others. And more, an innotive idea and relative optimizing structure forsynchronizer is presented to make the gear-changing flexible. Solid foundation is builtfor optimizing synchronizer performance.