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A Continuously Variable Power Split Transmission for Automotive Applications
ISSN: 0148-7191, e-ISSN: 2688-3627
Published February 24, 1997 by SAE International in United States
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Continuously variable transmissions, commonly known as CVT's, have been shown to be feasible alternatives to the conventional multi-step gear transmissions (standard or automatic) typically used in automotive applications. Most CVT applications, however, rely on a shaft-to-shaft transmission arrangement, in which the belt-sheave action limits the load capacity of the transmission, particularly at the high power ranges (low speed, high torque).
In this paper, a system based on a combined planetary gear train and a continuously variable pulley system is presented. The uniqueness of this arrangement is that the variable pulleys provide a power/torque split and recirculation function, which, when combined with the planetary gear train function, produces a continuously variable power split transmission system. The CVT ratio (r) is used as the regulator of the overall transmission ratio (R), in such a way that at low speeds, the power circulating through the belt can be only a fraction (less than 50%) of the total input power. Then, as the continuous shift is made to the high speed range, the power circulation shifts towards the CVT unit, a much desired feature in automotive applications.
|Technical Paper||Simulation of a Continuously Variable Power Split Transmission|
|Technical Paper||Development of a Large Torque Capacity Half-Toroidal CVT|
|Technical Paper||Claas CVT Development for Different Applications in Commercial Vehicles|
CitationMucino, V., Smith, J., Cowan, B., and Kmicikiewicz, M., "A Continuously Variable Power Split Transmission for Automotive Applications," SAE Technical Paper 970687, 1997, https://doi.org/10.4271/970687.
1997 Transmission and Driveline Systems Symposium: Transmission Systems, Components, Gears and Friction and Fluid Materials
Number: SP-1241 ; Published: 1997-02-24
Number: SP-1241 ; Published: 1997-02-24
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