Abstract
Traction drive CVT is a transmission changing the speed of output shaft continuously and smoothly. However, the speed ratio of the CVT is affected by the load torque - the increase of load torque generally makes the speed ratio lower. In this paper, effect of the load torque on the speed ratio of 2K-H type CVT equipping loading cam was investigated by the experiment focusing on the slip at contact zone in the unit. The experiment showed that the speed ratio drastically decreased when the load torque was quite small around zero, and that the change in speed ratio became moderate when the load torque became higher though the trend depended on the initial speed ratio. In addition, it was found that the slope of traction curve and traction coefficient at contact zone affected the speed ratio of the CVT.
