Patent ID: 6526343
Filing Date: 2003-02-25
Classification: F16H,Y10T

Abstract:
A system for controlling an automatic transmission of a vehicle having an input shaft connected to an internal combustion engine mounted on the vehicle and an output shaft connected to driven wheels of the vehicle, the transmission transmitting input torque, through any of frictional engaging elements, generated by the engine and inputted by the input shaft to the driven wheels by the output shaft, in accordance with predetermined shift scheduling defining a target gear based on detected operating conditions of the vehicle and the engine, comprising;input torque calculating means for calculating the input torque inputted to the transmission; desired torque calculating means for calculating a desired torque, at inertia-phase of shift, of one of the frictional engaging elements of the target gear to be shifted to, based on at least the calculated input torque and a predetermined value selected in a range of acceleration of gravity defined by upper and lower limits when defining the acceleration of gravity at a current gear now being engaged and the target gear as the upper and lower limits; hydraulic pressure calculating means for calculating hydraulic pressure to be supplied to the one of the frictional engaging elements based on at least the calculated desired torque; and hydraulic pressure control circuit for supplying hydraulic pressure to the one of the frictional engaging elements based on at least the calculated hydraulic pressure, wherein the transmission has a torque converter and the input torque calculating means includes: engine torque calculating means for calculating an engine torque generated by the engine in accordance with a predetermined characteristic based on at least an engine speed and an engine load of the detected operating conditions; inertial torque calculating means for calculating a parameter indicative of an inertia torque used raising the engine speed based on the engine speed; and torque converter torque ratio calculating means for calculating a torque ratio of the torque converter; and calculates the input torque based on at least the calculated engine torque, the calculated parameter and the calculated torque ratio.