| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a variable valve mechanism that changes operational characteristics of an engine valve by disposing a pair of cams between a pair of cams, the former cam pair having different characteristic from those of the latter cam pair, and sliding a rocker arm, for preventing an increase in size of the internal combustion engine as much as possible. <P>SOLUTION: Exhaust cams 47, 48 and intake cams 49, 50 are disposed on a camshaft 38. The intake cams 49, 50 are disposed between the exhaust cams 47, 48. A single intake-side rocker arm 37 to be brought into contact with the intake cams 49, 50 is moved in an axial direction of the camshaft 38 to be in contact with one of the intake cams, thereby changing operational characteristics of the intake valve 33. In the mechanism, a pressing part 37c of the intake-side rocker arm 37 for pressing down a pair of intake valves 33 is wide in the axial direction of the camshaft 38 and brought into contact with the pair of intake valves 33 simultaneously. When switching the operational characteristics is completed, at least one of both ends of the pressing part 37c is disposed radially outside the exhaust cams 47, 48. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
