http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
최재훈(Jaehoon Choi),서준호(Junho Suh),박노길(Nogil Park) 한국트라이볼로지학회 2020 한국트라이볼로지학회지 (Tribol. Lubr.) Vol.36 No.2
The electric vehicle industry is rapidly developing because of enforced environmental regulations, and several studies have been conducted on the multispeed transmission to improve the fuel efficiency of electric vehicles. Among these studies, research on the power density improvement of electric vehicle transmission is critical. Thus, the optimal design of the gear train is necessary to enhance transmission efficiency. In this study, an optimal design methodology for the lightweight two-speed transmission of electric vehicles is proposed. Because a multispeed transmission has many operating conditions and equality and inequality constraints, a new gear design method that combines analytical and iterative methods is applied without using complex optimization algorithms. Sets of possible design variables are generated considering the operating conditions and various design variables. The modules and face width ratios of each stage gear that satisfy the corresponding operating conditions are analytically calculated. The volume of the gear train is calculated, evaluated, and arranged using these values to determine the optimal solution for minimizing the volume, and the proposed methodology is applied to the actual model to verify its effectiveness. The design of a two-speed transmission with multiple operating conditions and constraints without complicated optimization algorithms can be optimized.
류정현(Jeonghyeon Ryu),성상훈(Sanghun Soong),박노길(Nogil Park) 한국자동차공학회 2002 한국자동차공학회 춘 추계 학술대회 논문집 Vol.2002 No.5_2
A continuously variable transmission (CVT) of a new type of traction drive consisting of a four-bar linkage and rotor with spherical surface is introduced. The fiction of this traction drive acts on the point where the interior surface of sphere contacts with the exterior one. The four-bar linkage is designed to give precise movement of the counter rotors and to extend the speed ratio range, which causes to improve the transmission performances when this model is applied to a split-power transmission system. The relationship between crank angle and follower angle is theoretically investigated and discussed on the desirable design considerations. For two cases of an offset-shafted transmission and a coaxial-shafted one, the variator speed ratio is also simulated with respect to the crank angle shows that all of negative, positive, zero, and infinite values can be included within the desirable crank angle range. The maximum contact stresses based on Hertz theory are compared with other traction drives. A simplified analysis shows that the proposed model have a significant advantage to increase the power density. Finally, the combining effect of the proposed model with an epicyclic gear train and the changing trend on variator speed ratio within the considered crank angle range showing enough possibility to apply to the infinite variable transmission (IVT) is discussed.
류정현(Jeonghyeon Ryu),김정훈(Jeonghun Kim),박노길(Nogill Park) 한국자동차공학회 2004 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
A new CVT. the Inner Spherical Traction CVT(ISCVT) for scooter is introduced. Transmission of the most scooters is the self-controlled variable pulley-belt type of CVT having some disadvantages in the fuel consumption and the limitation of the transmittable power due to the slippage between the belt and pulley. Unlike this, ISCVT controlled directly by driver is more efficient and the contact mechanism having the same line of contact normal of the spherical rotors of different radii on common center causes that the power density and torque capacity are remarkably improved. The prototype with the specifications of 50㏄ scooter is designed and tested.