Finite Element Analysis Of A Single-cone Synchronizer And The Fork’s Structure Optimization

At present, the research of synchronizer mainly focus on the test studies, theoretical physical modeling, dynamic simulation of shift process and the parts’ structure optimization. The test studies on synchronizer can reflect real shift process, but it cannot get the detailed movement and costs much; theoretical physical modeling and dynamic simulation of shift process concentrate on the analysis of components’ motion, shift force and time, but it lacks the study on some failure problems; the structure optimization generally depends on designer’s experience and test verification, like the structure improvement of fork and spring stiffness, but that’s inefficient.In this paper, a single-cone synchronizer of a commercial vehicle’s gearbox is studied. For further understanding of its strength fracture, wear and burning in reality, some virtual simulation techniques are applied to analyzing the shift process and the result of these failure problems. Based on the five periods of pre-synchronization, synchronization, disengaging, meshing and shift completion, a dynamic simulation is modeled to get some parameters, like shift force and fork’s displacement. Using the parameters, the finite element models with two different fork’s structure are created to analyze the reason of stress concentration and fractures. By means of topology optimization and shape optimization to the asymmetric fork, a new fork is produced and assembled to the synchronizer. The new single-cone synchronizer is analyzed and compared to the result of initial one, which verify the optimization effect.Above all, analyzing single-cone synchronizer is to improve design efficiency and shift quality, prolong the lifespan of asymmetric synchronizer.