Hydraulic control valve, e.g. for control unit of vehicle brakes or suspension

摘要

The hydraulic control valve has a plunger sliding over a fixed core inside a cylindrical bore in the valve housing. The inlet connection has a duct leading to a cross duct which is closed off by the plunger. As soon as the plunger starts to move the cross duct connects to the pressure space behind the plunger and provides hydraulic pressure to press pack the spring which holds the plunger in the closed position. A pressure relief bore through the plunger eventually equalises the pressure on both sides of the plunger and allows the spring to return the plunger into the off position. The other end of the core has a similar control bore which is shut off when the plunger moves.