Development of a Dual-Clutch Transmission System for ATVs

A demand for the easy driving made possible by automatic transmissions has been rising recently, even in the category of All-Terrain Vehicles (ATVs), which are mostly used off road. At the same time, from a practical usage point of view, users are still conscious of both fuel economy and drivability. Thus, the authors focused on developing a dual-clutch transmission system, which would combine the ease of use of an automatic transmission and the efficiency of a conventional manual transmission. Conventional dual-clutch transmission systems that have been developed for passenger vehicles are difficult and complicated to fit onto ATVs as they are. In particular, the shifting system complicates the total mechanism, by appending a number of parts as the control device. We therefore developed a new shifting system that consists of manual transmission components like dog-clutch type gears, a shift-drum system, and a shifting motor. A dog-clutch generates a hammering noise due to collision energy at the time of gear shifting. However, this collision energy can be reduced by shift timing and by motor control, which moderates the collision energy of the dog-clutch. A simple dual-clutch transmission for ATVs was thus developed.