| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To reduce journal hitting noises and a drive torque variation of a cam shaft when a fuel pump is driven by the cam shaft. <P>SOLUTION: The cam shaft 1 of an internal combustion engine is provided with a cam phase variable mechanism 100 and a pump drive cam 150 in addition to a valve drive cam 13 and drives the fuel pump 200. The cam phase variable mechanism changes a rotation phase of the pump drive cam relative to the valve drive cam in operation of the engine. In the idle operation of the engine, the rotation phase of the pump drive cam is changed to a position where pump drive reaction force and valve drive reaction force acting on the cam shaft are canceled each other and increase of hitting noises by the pump drive reaction force is inhibited. In engine operation states other than the idle operation, the rotation phase of the pump drive cam is changed to a position where pump drive reaction torque and valve drive reaction torque are canceled each other so that the drive torque variation of the cam shaft is inhibited and therefore life shortening of power transmission members such as a timing belt 7 is prevented. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
