Hybrid vehicle employing parallel hybrid system, using both internal combustion engine and electric motor for propulsion

An electronic driving torque control system for a hybrid vehicle employing a parallel hybrid system, using both an internal combustion engine and an electric motor for propulsion, the internal combustion engine having a variable valve timing control system mounted on at least an intake valve for variably adjusting an intake-valve closure timing and an electronic ignition system, said electronic driving torque control system comprising:

• a propulsion means having at least a first electric motor, an internal combustion engine, a clutch, a second electric motor, a transmission, and drive wheels, and constructed so that a crankshaft of the engine and a motor shaft of the first electric motor are connected to an input shaft of the clutch, and that a motor shaft of the second electric motor and an input shaft of the transmission are connected to an output shaft of the clutch to transmit a driving torque from the output shaft of the transmission to the drive wheels;
• an engine temperature sensor for detecting an engine temperature of the engine;
• a propulsion control means connected to said propulsion means and said engine temperature sensor, for disengaging the clutch and stopping the engine during a standstill state of the hybrid vehicle, and for propelling the hybrid vehicle by a driving torque generated by the second electric motor when the hybrid vehicle starts, and for starting up the engine by the first electric motor and engaging the clutch after engine startup, under a first specified engine-temperature condition where the engine temperature is above a predetermined temperature value;
• and
• an intake-valve closure timing control means connected to said variable valve timing control system for controlling an intake-valve closure timing to a predetermined retarded closure timing when the clutch is disengaged and for controlling the intake-valve closure timing to a predetermined advanced closure timing after the clutch is engaged, under the first specified engine-temperature condition.