| 摘要 |
An internal combustion engine of an automotive vehicle has a cylinder block formed with a cylinder bore, and a piston is fitted in the bore and reciprocates in it. A cylinder head is affixed to the cylinder block and defines a combustion chamber in cooperation with the piston and the cylinder bore. This cylinder head is formed with a portion which in cooperation with a portion of the piston defines a squish area of the combustion chamber, and with a coolant passage which substantially follows through the cylinder head adjacent to the squish area so as directly to cool the squish area. The coolant passage is of substantially the same cross sectional area along its extent. Thereby, the flow of coolant through the coolant passage is kept substantially uniform and at uniform speed throughout its extent, and cooling of the squish area is enhanced. If the squish area bulges inwards towards the central axis of the cylinder bore, then the inner wall of the coolant passage may bulge inwards so as to follow the inward bulging of the squish area; and in this case the outer wall of the coolant passage may likewise bulge inwards so as to follow this inward bulging of the inner wall of the coolant passage. The inlet or the outlet of the coolant passage may be restricted by a bulge defined by a portion of the cylinder head which surrounds a cylinder head bolt receiving hole formed in the cylinder head. |
