Combining both launch and reverse drive functions with the ratio change function in a geared neutral continuously variable transmission (GN-CVT), thus making a launch device like a torque converter and a drive-neutral-reverse set obsolete, is attracting considerable attention. This paper covers modelling and simulation of a V-belt type geared neutral transmission in and around the geared neutral point. Due to the specific nature of the geared neutral state, conventional driveline simulation models are shown to be inadequate. Experimental results are presented allowing for a more detailed description of the functional properties of the V-belt type variator, especially those related to small amounts of slip between the belt and the pulleys. The measured data will be analyzed to obtain grey model fitting parameters, which allow the data to be used in a simulation program, based on a dynamic driveline model. It will be shown that with a GN-CVT stall and launch performance can be considerably better than that to be achieved with a driveline with torque converter.
|Journal||Proceedings of the Institution of Mechanical Engineers. Part D : Journal of Automobile Engineering|
|Publication status||Published - 2005|