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 seat ( 30 ) 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 ). |