Patent ID: 9140337
Filing Date: 2015-09-22
Classification: B60K,B60L,B60W,F16D,F16H,Y02T,Y10T

Abstract:
1. Method for operating a powertrain comprising an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and an electric machine configured to selectively transmit mechanical power to an output member through selective application of a plurality of hydraulically actuated clutches, the method comprising: in response to a command to activate one of said clutches, monitoring a state of a pressure control switch operatively coupled to the clutch; operating the pressure control switch in one of a full feed state and an overlap state and monitoring a hydraulic line pressure utilized by said pressure control switch to fill said clutch; determining a hydraulic flow rate flowing to said clutch based upon said state of said pressure control switch and said hydraulic line pressure; tracking a clutch fill volume of said clutch based upon said hydraulic flow rate; estimating a clutch fill completion time based upon said clutch fill volume and said hydraulic flow rate and a time span wherein achieving clutch fill completion is expected based upon said clutch fill completion time; monitoring an output of a pressure switch operatively coupled to said clutch and detecting a fill completion based upon achievement of a clutch pressure calibrated to expected clutch fill completion independent of said estimating of the clutch fill completion time based upon said clutch fill volume and said hydraulic flow rate; indicating the clutch fill completion indicating said clutch is in a touching state,