| 摘要 |
<p>PURPOSE:To prevent a downward flow to an exhaust system through a cylinder at rest, regarding the air not contributing a combustion process, and reduce a pumping loss as much as possible. CONSTITUTION:A cam 42a for driving the second intake valve 34b in a cylinder 52 at rest is coupled to a camshaft 44 via a helical spline and both axial sides of the cam 42a are constrained with a stopper section 58 for restricting the slide thereof. The drive camshaft 44 is free to slide axially on the operation of a slide motion mechanism, and made to slide during the rest of an engine. The drive cam 42a for the second intake valve 32b is thereby 90 degrees rotated relatively in a rotation retarding direction, and the second intake valve 32b is made to open at compression stroke.</p> |
