Analyses and Evaluation on Synchronizer of Manual Transmission

Modern manual transmissions are equipped with synchronizer systems for better and more comfortable shifting performance. In this paper the typical structure of manual transmission assemble for heavy-duty vehicle is firstly introduced with emphasis on the power flow of 3^rd gear. Then the components of the synchronizer are introduced and the working process is analyzed theoretically. The synchronizer performance test rig is developed with which the actual working conditions are simulated. The shift robot is adopted instead of human being driver. The test data are recorded at 1 K sample rate while shifting. The test methods and evaluate methods are introduced. Finally, the synchronizers for main transmission are tested. The shifting process is analyzed qualitatively with the test curve.