Control device for internal combustion engine

Abstract

A control device for an internal combustion engine according to an embodiment includes: cooling units arranged on a path where a coolant is circulated, and cooling an exhaust gas of the internal combustion engine with the coolant flowing through the cooling units; a pump circulating the coolant; and ECUs estimating a heat quantity of the exhaust gas and deciding whether or not to operate the pump after an ignition switch is detected to be OFF in response to the estimated heat quantity of the exhaust gas.

1 . A control device for an internal combustion engine, comprising:
 a cooling unit arranged on a path where a coolant is circulated, and cooling an exhaust gas of the internal combustion engine with the coolant flowing through the cooling unit;   a pump circulating the coolant;   an estimation portion estimating a heat quantity of the exhaust gas, and   a control portion deciding whether or not to operate the pump after an ignition switch is detected to be OFF, in response to the estimated heat quantity of the exhaust gas   wherein the control portion decides whether or not to operate the pump after the ignition switch is detected to be OFF, in response to a period while the estimated heat quantity of the exhaust gas is higher than a decision value and in response to a period while the estimated heat quantity of the exhaust gas is lower than the decision value.   
     
     
         2 . The control device for the internal combustion engine of  claim 1 , wherein the pump is a mechanical pump in conjunction with the internal combustion engine, and the control portion operates the pump by performing idling after the ignition switch is detected to be OFF. 
     
     
         3 . The control device for the internal combustion engine of  claim 1 , wherein the pump is an electric pump operated in response to an instruction from the control portion. 
     
     
         4 . The control device for the internal combustion engine of  claim 1 , wherein
 the path includes: a primary path passing through the internal combustion engine; and a secondary path passing through the cooling unit and connected in parallel with the primary path,   a control valve is provided for controlling a flow rate of the coolant flowing through the primary path, and   the control portion suppresses a flow rate of the coolant flowing through the primary path by controlling the control valve after the ignition switch is detected to be OFF.   
     
     
         5 . The control device for the internal combustion engine of  claim 1 , wherein the control portion sets an operating period of the pump in response to a period while the estimated heat quantity of the exhaust gas is higher than a decision value. 
     
     
         6 . (canceled)