| 摘要 |
<p>In a combustion chamber of an engine, a first intake port (19), which is a straight port, has a throat (43) linearly formed and opened in a direction tangential to the inner periphery of a cylinder (11a) and produces a first swirl (S1), and a second intake port (20), which is a helical port, has a throat (44) spirally formed and produces a second swirl (S2) on the inside of the first swirl (S1), in the same direction as the first swirl (S1). Thus, the first and second swirls (S1, S2) that do not interfere with each other can be efficiently produced almost without bending the entire first and second intake ports (19, 20). The construction reduces processing cost of a cylinder head, makes the cylinder head compact, and simplifies the structure of the cylinder head.</p> |
