Basic Theory on a Multi-Mode CVT

다중모드 무단 변속기의 구조이론에 관한 연구

  • Published : 2000.10.01


A planetary gear assembly is a key component to combine and/or split a power from the source. With a planetary gear assembly, a continuously variable unit extends its capacity by means of power bra nching mechanism. Power branching with one planetary gear assembly and one continuously variable unit is categorized into 12 basic types. Each type represents peculiar power transmitting characteristics. Additionally, a multi-mode (range) continuously variable transmission can be designed with accompanying clutches. A multi-mode continuously variable transmission changes the path through which the source power is transmitted. Each path has its own features, such as high efficiency. In this paper, some design principles are examined such as, criteria to guarantee the minimum power efficiency, and constraints to guarantee the smooth mode shift after discussing well-known features of multi-mode M mathematically


Continuously Variable Transmission(CVT);Continuously Variable Unit(CVU);Infinitely Variable Transmission(IVT);Power Re-circulation/Split


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