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Abstract

A continuously variable power transmission (CVT) has a potential to present comfortable cruising, powerful acceleration, fuel economy and improvement of exhaust-gas emission as an automotive power transmission. There have been many developments of the half-toroidal traction-drive CVT since 1980 and ceaseless improvements on the traction material, synthetic fluid and efficiency continue to be made. This paper discusses some fundamental issues such as the influence of spin on the temperature rise of the traction surface, stress-cycle endurance of the traction element and heat transfer of the power roller, and shows the efficiency curve of the latest double-cavity CVT with a nominal input-torque capacity of 340 N m and rotational speed of 7000 r/min working at the maximum Hertzian pressure of 3.2 GPa.

Keywords

continuously variable power transmission half-toroidal traction-drive CVT automobile power-train

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Half-Toroidal Traction-Drive Continuously Variable Power Transmission

Abstract

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References