초록 ▼

Exhaust emission control is exercised to restrict the exhaust amounts [g] of HC, CO, NOx, and the like. However, since the intake air amount for startup unduly increases due to an engine speed overshoot for startup, the exhaust amounts of HC, CO, and NOx increase excessively. Therefore, there is a n

Exhaust emission control is exercised to restrict the exhaust amounts [g] of HC, CO, NOx, and the like. However, since the intake air amount for startup unduly increases due to an engine speed overshoot for startup, the exhaust amounts of HC, CO, and NOx increase excessively. Therefore, there is a need for optimizing the intake air amount for startup. The present invention proposes an engine startup control method that assures excellent startability and low exhaust emissions (small gas amount). Disclosed is an engine control device for starting an engine (from its stop state). The engine control device includes a section for setting a target engine operating state of each combustion; a section for detecting an actual engine operating state of each combustion; and a section for computing a control parameter for each subsequent combustion in accordance with the target engine operating state of each combustion and the actual engine operating state of each combustion.

대표청구항 ▼

What is claimed is: 1. An engine control device for starting an engine, comprising: means for setting a target engine operating state of each combustion; means for detecting an actual engine operating state of each combustion, which results when the engine is controlled to obtain the target engine

What is claimed is: 1. An engine control device for starting an engine, comprising: means for setting a target engine operating state of each combustion; means for detecting an actual engine operating state of each combustion, which results when the engine is controlled to obtain the target engine operating state; and means for computing a control parameter for at least one subsequent combustion in accordance with the target engine operating state and the actual engine operating state. 2. The engine control device according to claim 1, wherein a combination of the target engine operating state and the actual engine operating state is at least one of a combination of a target increased engine speed and an actual increased engine speed, a combination of a target torque and an actual torque, a combination of a target in-cylinder pressure and an actual in-cylinder pressure, and a combination of a target air amount and an actual air amount. 3. The engine control device according to claim 1, wherein the control parameter to be computed is at least one of an intake air amount, a fuel injection amount, ignition timing, intake/exhaust valve open/close timing, and an intake/exhaust valve lift amount. 4. The engine control device according to claim 1, wherein said means for computing the control parameter computes the control parameter from engine control parameter 1, which is derived from the target engine operating state, and engine control parameter 2, which is derived from the target engine operating state and the actual engine operating state. 5. The engine control device according to claim 1, wherein the control parameter is computed in accordance with the difference between the target engine operating state of each combustion and the actual engine operating state of each combustion. 6. The engine control device according to claim 1, further comprising: means for predefining a target engine operating state of each combustion for switching to a predetermined engine operating state from an engine stop state within a predetermined period of time. 7. The engine control device according to claim 6, further comprising: means for predefining a target increased engine speed of each combustion for attaining a predetermined engine speed from an engine stop state within a predetermined period of time. 8. The engine control device according to claim 7, further comprising: means for changing a predetermined target increased engine speed of each subsequent combustion in accordance with the actual increased engine speed of each combustion. 9. The engine control device according to claim 8, wherein the means for changing the predetermined target increased engine speed of each subsequent combustion changes the target increased engine speed of each subsequent combustion so that a predetermined engine speed is attained within a predetermined period of time. 10. The engine control device according to claim 7, further comprising: means for changing the target increased engine speed of a subsequent combustion to a value higher than the predefined target increased engine speed when the actual increased engine speed is lower than the target increased engine speed. 11. The engine control device according to claim 7, further comprising: means for changing the target increased engine speed of a subsequent combustion to a value lower than the predefined target increased engine speed when the actual increased engine speed is higher than the target increased engine speed. 12. The engine control device according to claim 1, further comprising: means for setting the target increased engine speed of each subsequent combustion in accordance with the target increased engine speed of each combustion and the actual increased engine speed of each combustion; and means for computing the target torque of each subsequent combustion or the target air amount of each subsequent combustion from the target increased engine speed of each subsequent combustion. 13. The engine control device according to claim 12, wherein a target air amount, a target fuel injection amount, target ignition timing, target intake/exhaust valve open/close timing, or a target intake/exhaust valve lift amount is computed in accordance with the target torque of each subsequent combustion. 14. The engine control device according to claim 12, further comprising: means for computing a target torque of each subsequent combustion in accordance with the target increased engine speed of each subsequent combustion and at least engine rotational inertia torque and/or friction torque. 15. The engine control device according to claim 1, further comprising: means for computing in-cylinder pressure or indicated mean effective pressure of a combustion from an intake air amount per cylinder of the combustion and a target fuel amount or a target air-fuel ratio per cylinder of the combustion; and means for computing friction torque from the in-cylinder pressure or the indicated mean effective pressure and an actual increased engine speed of the combustion. 16. The engine control device according to claim 1, further comprising: means for estimating a fuel evaporation rate or a fuel property of a combustion from an intake air amount per cylinder of the combustion, a target fuel amount or a target air-fuel ratio per cylinder of the combustion, and actual in-cylinder pressure or actual indicated mean effective pressure of the combustion; and means for computing friction torque from the actual in-cylinder pressure or the actual indicated mean effective pressure and an actual increased engine speed of the combustion. 17. The engine control device according to claim 1, wherein control is exercised over the first combustion upon engine startup and a predetermined number of subsequent combustions. 18. The engine control device according to claim 1, wherein the actual engine speed reaches a predetermined engine speed within a predetermined period of time after engine stoppage no matter whether fuel property, combustion efficiency, friction, atmospheric pressure, ambient temperature, or other environmental condition is changed.