| 摘要 |
<p>PURPOSE: To estimate an activated state of a catalyst with high accuracy by sensing an intake amount of an engine, and computing an integration value of heat quantity supplied to the catalyst based on the sensed intake amount. CONSTITUTION: In a control unit 12, a cooling water temperature Tw of an engine 1 is sensed by a water temperature sensor 15, and a reference quantity of heat Cϕis set while corresponding the initial cooling water temperature Tw to an initial temperature of the catalyst 10. When the reference quantity of heat Cϕis not zero, the catalyst is determined not to be activated. Warming-up control is started for early activation of the catalyst. When the engine 1 is not in a fuel cut state nor an idling state, quantity of heat A supplied to the catalyst 10 from exhaust is estimated and computed based on the intake air amount Q which is sensed by an air flow meter 13. The calculated quantity of heat A is added to the former integration value CHn-1 to obtain the present integration value CHn . When the quantity of heat integration value CHn exceeds the reference quantity of heat Cϕ, the catalyst 10 is determined to be activated, and warming-up control is completed.</p> |
