| 摘要 |
<p>The invention provides a water jacket structure for a cylinder head, and can realize improvement of cooling efficiency of a collector and suppress retention of gas and air during casting. The water jacket structure for the cylinder head has a plurality of upper combustion chamber portions (21), a plurality of exhaust openings (23), a collector (24) collecting the plurality of exhaust openings, and an upper outlet water jacket (80) and a lower outlet water jacket (90) which are respectively arranged at upper and lower sides relative to the collector. Mutually independent flow channels are formed in the upper outlet water jacket (80) and the lower outlet water jacket (90). The lower outlet water jacket (80) has a protruding portion (81), and the lower outlet water jacket has a protruding portion (91). The protruding portions (81, 91) are spaced from each other at a predetermined interval in a cylinder axis direction, and the protruding quantity L1 of the protruding portion (81) is smaller than the protruding quantity L2 of the protruding portion (91).</p> |
