| 摘要 |
A valve gear for an internal combustion engine capable of promptly switching the position of a piston in a rocker arm to thereby change the engine operating condition with a satisfactory response, even in a low rotation region in which an adequate amount of oil discharged from an oil pump cannot be expected. Depending on positions of pistons slidably fitted in low-speed and high-speed cylinder portions provided in an intake driven rocker arm, a low-speed or high-speed drive rocker arm is selectively operated to press a corresponding one of the pistons. The piston in the low-speed cylinder portion switched in a low rotation region is made smaller in diameter than the piston in the high-speed cylinder portion, to be enabled to be promptly switched. |
