Range Shift Fork Wearing Test Analysis On Heavy Manual Transmission

Along with the rapid development of China automobile market, transmission is facingbig opportunity as well. The manual transmission mainly use different gear sets to generatevariable speed and torque. The working condition of shift fork and range clutch wearingcouple in range shift system is very severe, such as shock load, relative motion in high loadand relative sliding in high speed difference etc. So the shift fork wearing resistance is oneof the key elements during transmission product design. Based on the development projectof range shift fork system, structure characteristics study, wearing root cause investigation,design optimization and DOE method were performed to find the design and improvementproposal. The main work of this thesis is summarized as follows:1. Performed structural mechanics analysis and FEA to know force condition on rangeshift fork system. Identified shift fork force and stress/strain distribution, and found out theoptimization direction.2. Further studied on the severe wearing issue, and evaluated the design and lube intesting to find the key factor. A serial of feasible development and optimization ideas wereproposed.3. Used DOE method on several very likely proposals and designed accelerated testingbased on the tough project lead time. The data after testing was analyzed by different ways,like regression, statistics, normality and reliability. Finally the optimization solution tosolve shift fork wearing issue was found and confirmed.This thesis provided solution for product development and real engineering technicalproblem, and thought map/approach for transmission or similar products development andapplication as well.