Patent ID: 7920950
Filing Date: 2011-04-05
Classification: B60W,F02D

Abstract:
1. A vehicle drive torque estimation device in a vehicle having an engine, a torque converter connected to the output shaft of the engine, and a transmission mechanism that changes the speed of the output rotation transmitted from the engine via the torque converter and transmits the result to wheels, the vehicle drive torque estimation device comprising: first drive torque calculation means for calculating the engine estimated drive torque based on an amount of air taken into the engine; second drive torque calculation means for calculating the engine estimated drive torque based on the speed of rotation of the output shaft of the engine; slip ratio calculation means for calculating a slip ratio of the torque converter; running condition determination means for determining whether the transmission mechanism is in gear or not; rotation speed measurement means for measuring the speed of rotation of the output shaft of the torque converter; wheel speed measurement means for measuring the rotation speed of the wheels; and torque combination means for calculating a combination drive torque by combining a first estimated drive torque calculated by the first drive torque calculation means and a second estimated drive torque calculated by the second drive torque calculation means in a predetermined proportion, wherein if the slip ratio calculated by the slip ratio calculation means is equal to or less than a predetermined value, and if the first estimated drive torque is greater than the second estimated drive torque, the torque combination means calculates the combination drive torque as the engine estimated drive torque, and wherein if the running condition determination means determines that the transmission mechanism is in gear, and if the speed of rotation of the output shaft of the torque converter measured by the rotation speed measurement means is equal to or less than a predetermined speed of rotation, and if the rotation speed of the wheels measured by the wheel speed measurement means is equal to or greater than a predetermined rotation speed, the torque combination means calculates the first estimated drive torque as the engine estimated drive torque even if the slip ratio is equal to or less than a predetermined value, and even if the first estimated drive torque is greater than the second estimated drive torque.