Cooling apparatus of internal combustion engine

Abstract

A cooling apparatus of an internal combustion engine according to the invention comprises a first passage formed in the cylinder block, through which the cooling medium flows for cooling between-bores portions, a second passage formed in the cylinder block, through which the cooling medium flows for cooling a bore-surrounding portion, and a cooling medium supplying mechanism for supplying the cooling medium to the first and second passages such that ability of the cooling medium for cooling the between-bore portions, is different from the ability of the cooling medium for cooling the bore-surrounding portion.

What is claimed is: 
     
         1 . A cooling apparatus of an internal combustion engine for cooling a cylinder block of the internal combustion engine and a cylinder head mounted on the cylinder block by cooling medium, comprising:
 a first passage formed in the cylinder block, through which the cooling medium flows for cooling between-bores portions each corresponding to a portion of the cylinder block surrounding and between adjacent cylinder bores formed in the cylinder block;   a second passage formed in the cylinder block, through which the cooling medium flows for cooling a bore-surrounding portion corresponding to a portion of the cylinder block surrounding the cylinder bores other than the between-bores portions; and   a cooling medium supplying mechanism for supplying the cooling medium to the first and second passages such that ability of the cooling medium for cooling the between-bore portions, is different from the ability of the cooling medium for cooling the bore-surrounding portion.   
     
     
         2 . The cooling apparatus according to  claim 1 , wherein the cooling medium supplying mechanism includes a head passage formed in the cylinder head, through which the cooling medium flows for cooling the cylinder head, and the first passage is connected to the head passage. 
     
     
         3 . The cooling apparatus according to  claim 1 , wherein the cooling medium supplying mechanism includes:
 a common passage communicated with the first and second passages; and   a flow rate control valve for controlling a flow rate of the cooling medium supplied to the second passage via the common passage.   
     
     
         4 . The cooling apparatus according to  claim 1 , wherein the cooling medium supplying mechanism includes:
 a first cooling device for cooling the cooling medium supplied to the first passage; and   a second cooling device for cooling the cooling medium supplied to the second passage, and   ability of the first cooling device of cooling the cooling medium is larger than the ability of the second cooling device of cooling the cooling medium.