| 摘要 |
PURPOSE:To improve drivability for a car ever so better, by installing a primary suction port being usually serviceable and a secondary suction port being closed in time of low speed and low load operations, while securing a cover, having an interconnecting port prescribing its opening direction, to an opening end leading to the inside of a combustion chamber of the secondary suction port. CONSTITUTION:Both primary and secondary suction ports 3, 4 and an exhaust port 5 are all made to open to a semispherical combustion chamber 2 to be formed in a cylinder head 1, and each of these ports is opened or closed by suction valves 6, 7 and an exhaust valve 8. The primary suction port 3 is formed to be smaller in diameter than the secondary port 4 and made to open so touching a peripheral edge of the combustion chamber 2, making it inhale an air-fuel mixture only from the suction port 3 in time of low speed and low load operations. On the other hand, a caplike cover 44 is secured to an opening end of the primary suction port 3 so as to cover the opening. This cover 44 is made up of installing an interconnecting port 44a prescribing a sense of suction air flowing inside the combustion chamber 2 from the port 3, and with this, a swirl is made so as to be produced inside the combustion chamber 2. |
