Engine cooling apparatus

Abstract

A cooling apparatus is equipped with a cylinder block in which is provided and a cylinder head in which is provided. The first causes cooling water to flow through an exhaust-side portion of the cylinder block. Further, the first causes the cooling water to flow through an exhaust-side portion of the cylinder head including a predetermined region around a spark plug. The second is incorporated into a second circulation path different from a first circulation path into which the first is incorporated. The second causes the cooling water to flow through an intake-side portion of the cylinder block. Further, the second causes the cooling water to flow through an intake-side portion of the cylinder head.

1 . An engine cooling apparatus comprising:
 a cylinder block and a cylinder head in which a first cooling medium path and a second cooling medium path through which a cooling medium is caused to flow are provided,   the first cooing medium path causing the cooling medium to flow through an exhaust-side portion of the cylinder block and thereafter causing the cooling medium to flow through an exhaust-side portion of the cylinder head including a predetermined region around a spark plug provided to the cylinder head, and   the second cooling medium path being incorporated into a cooling medium circulation path different from that into which the first cooling medium path is incorporated, and causing the cooling medium to flow through an intake-side portion of the cylinder block and thereafter causing the cooling medium to flow through an intake-side portion of the cylinder head.   
     
     
         2 . The engine cooling apparatus according to  claim 1 , further comprising cooling medium control means that causes the cooling medium to flow through the first cooling medium path when the cooling medium is circulated through the engine and makes a flow rate of the cooling medium that flows through the second cooling medium path at low or medium load lower than that at high load. 
     
     
         3 . The engine cooling apparatus according to  claim 2 , wherein the engine is an engine in which exhaust recirculation is performed, and the engine cooling apparatus further comprises a cooling device capable of cooling exhaust returned to the engine by a thermal exchange with the cooling medium circulated, and a first branch portion splitting the cooling medium that flows through the first cooling medium path into a flow that passes through the cooling device. 
     
     
         4 . The engine cooling apparatus according to  claim 2 , further comprising a heater capable of heating air by a thermal exchange with the cooling medium circulated, and a second branch portion splitting the cooling medium that flows through the first cooling medium path into a flow that passes through the heater. 
     
     
         5 . The engine cooling apparatus according to  claim 3 , further comprising a heater capable of heating air by a thermal exchange with the cooling medium circulated, and a second branch portion splitting the cooling medium that flows through the first cooling medium path into a flow that passes through the heater.