Engine cooling device

Abstract

The cooling device is provided with an ECU, a water pump, an engine, a water-cooled exhaust manifold, and a radiator. A first flow rate determination means that determines the flow rate of the cooling water allowed to flow through the water-cooled exhaust manifold based on the intake air flow rate when the operation state of the engine is in a steady state, and a second flow rate determination means that determines the flow rate of the cooling water allowed to flow through the water-cooled exhaust manifold based on the cooling loss when the operation state of the engine is in a transient state are functionally achieved by the ECU.

1 . An engine cooling device comprising:
 a coolant pumping device that pumps a shared coolant to a plurality of coolant circulation paths;   an engine of which an engine body is mounted in at least one of the plurality of coolant circulation paths;   an exhaust system cooling unit which is mounted in at least one of the plurality of coolant circulation paths, of which a heat capacity is smaller than that of the engine body, and which cools an exhaust system of the engine by a flowing coolant;   a cooling device that is mounted in at least one of the plurality of coolant circulation paths, and cools a flowing coolant; and   a flow rate determination unit that estimates a cooling loss of an exhaust system based on an intake air flow rate of the engine, and determines a flow rate of a coolant allowed to flow through the exhaust system cooling unit.   
     
     
         2 . An engine cooling device comprising:
 a coolant pumping device that pumps a shared coolant to a plurality of coolant circulation paths;   an engine of which an engine body is mounted in at least one of the plurality of coolant circulation paths;   an exhaust system cooling unit which is mounted in at least one of the plurality of coolant circulation paths and cools an exhaust system of the engine by a flowing coolant, and of which a heat capacity is smaller than that of the engine body;   a cooling device that is mounted in at least one of the plurality of coolant circulation paths and cools a flowing coolant; and   a flow rate determination unit that determines a flow rate of a coolant allowed to flow through the exhaust system cooling unit based on a received heat amount that a coolant receives from an exhaust in the exhaust system cooling unit.   
     
     
         3 . The engine cooling device according to  claim 1 , further comprising:
 an estimation unit that estimates a temperature of a wall, which forms a flow path through which an exhaust gas flows, of the exhaust system cooling unit; and   a correction unit that corrects a flow rate of a coolant determined by the flow rate determination unit based on the estimation.   
     
     
         4 . The engine cooling device according the  claim 2 , further comprising:
 an estimation unit that estimates a temperature of a wall, which forms a flow path through which an exhaust gas flows, of the exhaust system cooling unit; and   a correction unit that corrects a flow rate of a coolant determined by the flow rate determination unit based on the estimation.