| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent overheating of an oil passage and a head bolt insertion hole boss part. <P>SOLUTION: A partition wall 8 partitioning exhaust ports 5 of neighboring cylinders #2, #3 extends to an exhaust manifold part 6 from between the neighboring cylinders #2, #3, and a head bolt insertion hole 11c is formed in the partition wall 8 in a cylinder head. A heat insulation layer 22 is formed in the partition wall 8 between a tip part 8a of the partition wall 8 facing the exhaust manifold part 6 and the head bolt insertion hole 11c. An oil passage 23 is formed at a center part of the heat insulation layer 22. The heat insulation layer 22 is extended in a circular arc manner about an axial line of the head bolt insertion hole 11c along substantially a half of an outer periphery of the head bolt insertion hole boss part 17 on a partition wall tip part 8a side. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
