Six-speed automatic gearbox transmission mechanism for optimizing transmission ratio

Disclosed is a six-speed automatic gearbox transmission mechanism for optimizing a transmission ratio. The six-speed automatic gearbox transmission mechanism comprises an input device, an output device, three planetary gear assemblies, three connecting components, three brakes and three friction clutches, and all the components are arranged in a gearbox shell. According to the six-speed automatic gearbox transmission mechanism, six advancing speed ratios or transmission ratios and reverse gears can be achieved, the structure is compact, the size is small, mounting space is saved, the transmission ratio drive power achieves 0.8632, the efficiency of a gearbox is excellent, and the minimum efficiency value achieves 0.955.