A FUEL SYSTEM COMBINATION VALVE FOR COMBUSTION ENGINE AND SUCH A FUEL SYSTEM

摘要

The invention relates to a combination valve(15)for pressure control and venting in a fuel system for delivering fuel to an internal combustion engine.The valve comprises a primary valve cone(25),which is supported so that it is displaceable between two limit positions in a cylinder bore(24)in a valve housing(23),against the action of a first spring element(26).The displacement of the valve cone from an inoperative limit position into an operative limit position leads to the opening of a connection between an inlet duct(32)and an outlet duct(33)in the valve housing.The valve cone(25)is provided with an inner passage(27),which is designed to accommodate a secondary valve cone(28).This is displaceable between a support surface(29)and a valve sea against the action of a second spring element(31)having a lower spring constant than the first spring element.A displacement of the secondary valve cone against the action of the second spring element(31)leads to the opening of a connection between the inlet duct(32)and a venting duct(34).