A STUDY OF AUTOMATIC MECHANICAL TRANSMISSION BASED ON A TWELVE-SPEED GEARBOX

摘要

Adopting as many as possible shift gears is an important measure to reduce fuel consumption, and it is also a trend of the development of gearbox. The paper analyzes one kind of 12-speed manual gearbox, and summarizes the motional principle of the changing gear mechanism and the operational principle of changing gears of this manual transmission case. Based on this analysis, an ECU which is independent of the whole vehicle control system and a pneumatic actuator is designed in order to substitute the manual shifting mechanism. Through hereinbefore study we change this 12-speed manual transmission to an automatic mechanical transmission (AMT). We design the auto-shift principle of this gear box by matching this 12-gear gearbox and the corresponding engine of the experimental truck so as to get the optimal power performance and economical performance. We adjust this auto-shift rule several times by analyzing the collected data in road tests, and the final road test shows that the truck with automatic mechanical transmission has particular advantage in fuel consumption compared with the truck using manual transmission.