| 摘要 |
<p>Provided is a spark ignition type internal combustion engine comprising a variable compression ratio mechanism (A) capable of changing a mechanical compression ratio, and a variable valve timing mechanism (B) capable of controlling the closing timing of an intake valve. At an engine low-load running time, the mechanical compression ratio is made so higher than that at an engine high-load running time that the expansion ratio may be 20 or higher. In case the vacuum in an engine intake passage is lower than the required vacuum, the opening of a throttle valve (17) is reduced, and the valve closing timing of the intake valve is controlled so that the intake air in a quantity according to the engine load may be fed to the inside of a combustion chamber in accordance with the opening of the throttle valve. As a result, a brake booster or the like can be properly activated in the internal combustion engine having its mechanical compression ratio enlarged at the engine low-load running time.</p> |
