Patent ID: RE39684

Claim:
System for controlling selection of gear position for an automatic transmission of an automobile comprising: weight estimation means for estimating a total weight of said automobile; acceleration input means for receiving an acceleration signal indicative of acceleration of said automobile; output torque estimation means for estimating an output torque based on torque characteristics of a drive train of said automobile; running load estimation means for estimating a running load from the estimated weight of the automobile, the acceleration, and the estimated output torque; memory means for storing at least two shift schedules therein; a shift schedule variable-control unit which determines a shift schedule of an automatic transmission of said drive train during actual running of said automobile on the basis of the estimated running load, the estimated weight of the automobile and the stored shift schedules; and gear shift determination means for selecting a gear position of said automatic transmission based on the determination shift schedule; wherein said output torque estimation means estimates said output torque based on torque characteristics of an engine of said drive train when a ratio between an input revolution speed and an output revolution speed of said torque converter is greater than a predetermined value, and based on torque characteristics of a torque converter of said automatic transmission when said ratio is less than said predetermined value.