| 摘要 |
<P>PROBLEM TO BE SOLVED: To enhance fuel economy of an internal combustion engine which requires much fuel for outputting required torque to an internal combustion engine in the case where a combustion efficiency is reduced as a combustion temperature in a combustion chamber decreases. <P>SOLUTION: This valve gear lifts an intake valve 1 of the internal combustion engine, and has a lift amount change mechanism for changing lift amount of the intake valve. This valve gear comprises: a determining means for determining whether it is effective or not for enhancing the fuel economy by increase of a compression ratio in the combustion chamber 8; and a compression ratio increasing means which increases, when it is determined to be effective by the determining means, the compression ratio in the combustion chamber by opening an exhaust valve from a time after intake stroke to a time in which a pressure in the combustion chamber is made equal to a pressure in an exhaust passage. <P>COPYRIGHT: (C)2004,JPO |
