Engine controlling apparatus

1. An engine controlling apparatus, comprising:

an engine speed detection unit that detects an engine speed of an engine mounted on a vehicle;

an acceleration operation amount detection unit that detects an acceleration operation amount inputted to an acceleration pedal of the vehicle;

a first calculation unit that calculates an acceleration demand torque based on the engine speed detected by said engine speed detection unit and the acceleration operation amount detected by said acceleration operation amount detection unit;

a second calculation unit that calculates an external demand torque, a first demand torque and a second demand torque, the external demand torque being demanded from an external controlling system, the first demand torque being for ignition timing control, the second demand torque being for intake air amount control, both the first demand torque and the second demand torque being calculated based on the acceleration demand torque and the external demand torque;

a third calculation unit that calculates a first target torque for ignition timing control and a second target torque for intake air amount control, the first target torque being calculated based on the first demand torque, the second target torque being calculated based on both the second demand torque and an air intake delay in an intake system of the engine;

a fourth calculation unit that calculates, as an actual torque, a maximum torque which can be generated by the engine at an actual charging efficiency; and

a control unit that controls an ignition timing of the engine based on the actual torque and the first target torque, wherein

said second calculation unit includes a first external demand torque calculation section and a second external demand torque calculation section, and

said second external demand torque calculation section applies correction to both the first demand torque and the second demand torque, and

said first external demand torque calculation section applies correction for stabilizing the posture of the vehicle only to the second demand torque.

2. The engine controlling apparatus according to claim 1 , wherein

said control unit controls the ignition timing of the engine based on a ratio between the first target torque calculated by said third calculation unit and the actual torque calculated by said fourth calculation unit.

3. The engine controlling apparatus according to claim 2 , wherein

said control unit includes a storage unit that stores a correspondence relationship between the ratio between the first target torque and the actual torque and a retard amount of the ignition timing of the engine.

4. The engine controlling apparatus according to claim 3 , wherein

said control unit further includes a second storage unit that stores a correspondence relationship among the ratio, the retard amount and the engine speed detected by said engine speed detection unit.

5. The engine controlling apparatus according to claim 1 , further comprising:

an intake controlling unit that controls an amount of intake air to be introduced into the engine; wherein

said first calculation unit carries out a first-order delay calculation taking a response delay of the intake into consideration for a value calculated based on the engine speed and the acceleration operation amount to calculate the acceleration demand torque.

6. The engine controlling apparatus according to claim 1 , further comprising:

an intake air amount detection unit that detects an amount of intake air to be introduced into the engine; and

an actual charging efficiency calculation unit that calculates the actual charging efficiency based on the intake air amount detected by said intake air amount detection unit.

7. The engine controlling apparatus according to claim 1 , wherein

the external controlling system includes an automatic transmission controlling apparatus, and

said second calculation unit calculates the external demand torque based on a torque value demanded from the automatic transmission controlling apparatus.