Torque Reversal Lash Impact Load Mitigation Method By Slipping A Traction Clutch

摘要

The present invention provides an algorithm to provide slip across a traction clutch during a torque reversal event to prevent impact loading on the system. This method diverts the energy associated with a torque reversal impact load to the slipping clutch in the form of heat. The algorithm shall be initiated when a torque reversal is initiated by operator input. At the initiation of a torque reversal 1 the algorithm shall drop pressure on the traction clutch to a pressure 2 low enough to allow slip across the clutch before the torque sign changes 3. When positive slip which is determined by the input side is faster than the output side of the clutch is measured 4, the algorithm shall begin to ramp clutch control pressure back in 5. This shall be done in a manner proportional to currently provided torque. Once measured clutch slip is back below a threshold the clutch shall be commanded back to full pressure 6.