| 摘要 |
<p>A valve operation control system for an internal combustion engine in which hydraulic pressure applied to a valve operation mode changing mechanism is controlled by hydraulic pressure control means that is formed from a holder mounted on a cylinder head, a spool valve formed by slidably housing a spool valve body in a valve body, and an electromagnetic open/close valve for controlling hydraulic pressure of a pilot hydraulic chamber, wherein the holder (109) is formed by integrally connecting a housed portion (109a) and a projecting portion (109b) by means of a connection portion (109c), the housed portion (109a) being housed between the cylinder head (22R) and a head cover, the projecting portion (109b) projecting outside the cylinder head (22R) and the head cover and having the electromagnetic open/close valve (113, 114) mounted thereon, a seal face (116) with the head cover is formed on the connection portion (109c), and the valve body (110) is provided so as to be connected to the housed portion (109a) while being housed between the head cover and the cylinder head (22R). This enables the sealing properties between the holder and the head cover to be enhanced.</p> |
