Determining fill time for friction elements of automatic gearbox involves neutral compensation, drive compensation and computation of fill time from computed piston stroke ratios

摘要

The method involves neutral compensation, whereby a piston stroke ratio is adapted by detecting an N-range change time and using it and a pre-set chart when a change from drive to neutral or reverse is detected, drive compensation by detecting the D/R region change time and using it with the pre-set chart if a change to neutral is detected, and computation of the fill time using the computed piston stroke ratios. Independent claims are also included for the following: a system for determining fill time for friction elements of automatic gearbox.