Patent ID: 7051958

Claim:
In a fuel injection valve for internal combustion engines, comprising a housing ( 1 ), in which in a bore ( 16 ) an outer valve needle ( 20 ) and an inner valve needle ( 22 ) guided in it are disposed, in which the outer valve needle ( 20 ), in a closing position, comes to rest on a valve seat ( 24 ) disposed on the end toward the combustion chamber of the housing ( 1 ) and by means of a longitudinal motion in an opening direction opens an outer row ( 130 ) of injection openings, and the inner valve needle ( 22 ) likewise rests on the valve seat ( 24 ) in a closing position and by means of a longitudinal motion in an opening direction opens an inner row ( 230 ) of injection openings, to which rows ( 130 , 230 ) of injection openings, in the opened state of the valve needles ( 20 ; 22 ), fuel under pressure flows from a pressure chamber ( 26 ) embodied in the housing ( 1 ) and from there is injected into the combustion chamber of the engine, a pressure shoulder ( 27 ), which is embodied on the outer valve needle ( 20 ) and is acted upon by the fuel pressure in the pressure chamber ( 26 ), so that as a result, a force acting in the opening direction on the outer valve needle ( 20 ) results, a pressure face ( 36 ) on the inner valve needle ( 22 ), which face, after the outer valve needle ( 20 ) has lifted from the valve seat ( 24 ), is acted upon by fuel pressure in the opening direction, a high-pressure conduit ( 10 ), extending in the housing ( 1 ), which discharges into the pressure chamber ( 26 ), and in which fuel at high pressure is always present, and having a fuel-filled control pressure chamber ( 52 ), whose pressure is controllable and by means of whose pressure, at least indirectly, a closing force is exerted on the inner valve needle ( 22 ), a fuel-filled control chamber ( 50 ), embodied in the housing ( 1 ) by whose pressure, at least indirectly, a closing force is exerted on the outer valve needle ( 20 ), an inlet throttle ( 70 ), through which the control chamber ( 50 ) communicates with the high-pressure conduit ( 10 ), an outlet throttle ( 72 ), by way of which the control chamber ( 50 ) can be made to communicate with a pressureless leak fuel chamber ( 78 ), and the outlet throttle ( 72 ) is closable by a control valve ( 58 ), and the outlet throttle ( 72 ) and the inlet throttle ( 70 ) are dimensioned such that when the outlet throttle ( 72 ) is open, more fuel flows out of the control chamber ( 50 ) than flows to it through the inlet throttle ( 70 ), and a connection ( 55 ) between the control chamber ( 50 ) and the control pressure chamber ( 52 ), the control pressure chamber ( 52 ) being closed off except for the connection ( 55 ), and the connection ( 55 ) is dimensioned such that upon opening of the outlet throttle ( 72 ) by the control valve ( 58 ), the pressure first drops in the control chamber ( 50 ) and only drops in the control pressure chamber ( 52 ) as well after a time lag.