摘要 |
A directional solenoid valve for engine valve lift control includes a poppet guide having a first port, a second port in communication with the first port, and a valve seat between the first port and the second port. The valve further includes a poppet slidably moveable in the poppet guide between a first position where the poppet is seated against the valve seat and a second position removed from the valve seat. A bias force is generated to move the poppet relative to the guide under pressure on either (i) a differential area of the poppet guide less a seat area in communication with the first port or (ii) the seat area in communication with the second port, relative to opposing pressure on an opposing side of the poppet. |