Patent 7967721 was granted and assigned to Hitachi on June, 2011 by the United States Patent and Trademark Office.
A transmission system in a vehicle using a motor to transmit power assists acceleration by generating auxiliary engine power during acceleration in addition to gear changing by the motor. Where acceleration assistance is added, torque transition is conducted along a torque transmission route of dog clutch, second intermediate shaft, motor, first intermediate shaft, and gear position of first intermediate shaft before shifting so as to avoid the torque reduction in uncomfortable shocks and feelings to the driver due to torque reduction when shifting.