The Research And Design Of Synchronizer Test-bench Of Commercial Vehicle Transmission

Synchronizer is the key component of an automobile gearbox during the shifting. It can make shifting gears of different speeds not mesh until they achieve the same speed, avoiding noise and impact between gear teeth in the shifting process. Its performance plays an important role in improving shifting stability and acceleration performance of auto starts. As automotive structures have become increasingly complex, working conditions of synchronizers can not be accurately simulated, making the study of synchronizers’ properties become very hard. Thus, conducting relevant tests on synchronizer is a critical part of product development process. In order to ensure the quality of synchronizers as well as enhance research and development capabilities, designing an advanced automotive synchronizer test bench for accurate performance tests has far-reaching significance.This project has adequately studied the working principle of synchronizer, referred to related technical data of test bench at home and abroad, and developed a synchronizer test bench according to relevant national synchronizer test standards.The author has mainly completed the design of mechanical part of the test bench and hardware parts of control system, and developed the test software based on LabVIEW virtual instrument. The test bench uses AC motor to drive its mechanical part and controls the motor speed by adjusting the frequency converter. Shift control mechanism uses the servo motor to provide the drive. As to the measurement and control part, the author mainly build its hardware structure and write the test program based on LabVIEW to automatically control the action of the test rig. Furthermore, virtual laboratory instruments have also been built to complete data acquisition, graphical display and data management.Finally, this test bench has conducted a performance test on a certain type of synchronizer. The test data has been analyzed and they are consistent with theoretical results. Therefore, it can be concluded that this synchronizer performance test bench can run normally, perform stably and meet the design requirements.