| 摘要 |
PURPOSE:To improve water cooling performance around a combustion chamber by a simple structure by drilling a pair of cooling-water inflow ports onto the bottom wall of a cylinder head set between the contiguous combustion chambers and installing an introducing groove and a rib piece onto the bottom surface of a water jacket. CONSTITUTION:A portion of the cooling water supplied from a water jacket on a cylinder block side flows into a water jacket 14 on a cylinder head 1 side, passing through a pair of cooling-water inflow ports 15 between the contiguous combustion chambers 3. Then, the cooling water is guided by a pair of inclined guide walls 17, led by an introducing groove 18, and flows into the center part of the water jacket 14, spreading to the right and left combustion chambers 3 sides. Further, the cooling water is branched into the upper part of the center part of the right and left combustion chambers 3, direction-changed through the leading by a rib piece 16. Therefore, the cooling water flows along the upper wall of the combustion chamber 3, outer walls of intake and exhaust ports 9 and 10, and the outer wall of the accommodation cylinder of a spark plug 12, and efficiently cool them. |
