Abstract: In a dual-fuel fuel injector comprising a first injector unit for a first injector operating mode using a first main fuel and a second injector unit for a second injector operating mode using a second main fuel and an injector-reservoir, the reservoir is connected at one end to a first main fuel supply and at the opposite end to a second main fuel supply with a separating element disposed in the injector reservoir so as to be movable between the opposite ends so that, in each operating mode, the full volume of the reservoir can be used for accommodating the respective main fuel.

Abstract: A dual fuel fuel-injector including a first nozzle body having a plurality of respective receptacles, a plurality of nozzle needles, each having a stroke that is controllable by a control fluid and at least one associated control chamber. The plurality of nozzle needles include a plurality of first nozzle needles, each being axially displaceable in the first nozzle body of the dual fuel fuel-injector for selective discharge of a first fuel, whereby the plurality of first nozzle needles are arranged in the first nozzle body in the plurality of respective receptacles. The dual fuel fuel-injector also includes a mixed leakage collecting channel communicatively connected to the plurality of respective receptacles, and a mixed leakage discharge channel on the dual fuel fuel-injector and in communication with the mixed leakage collecting channel.

Abstract: The invention relates to a dual-fuel fuel injector that includes a plurality of stroke-controllable gas nozzle needles which are axially movably mounted on the dual fuel fuel-injector in a plurality of respective seats and which are distributed in a circumferential direction of the dual fuel fuel-injector, and a nozzle chamber provided for the plurality of stroke-controllable gas nozzle needles. The nozzle chamber includes a plurality of externally positioned bulges, wherein within each respective cross section of which an inlet cross section of a flow path is defined which can be blocked selectively via a respective stroke-controllable gas nozzle needle of the plurality of stroke-controllable gas nozzle needles to at least one nozzle opening.

Abstract: A flow limiting valve, comprising a valve body adjustable between a closed position and an open position, wherein in the open position a flow channel for a conveying fluid is opened in the flow limiting valve and in the closed position the flow channel is closed, whereby the adjustment of the valve body is subject to conveying fluid pressure; wherein a control valve is integrated into a housing of the flow limiting valve through which the valve body is adjustable between open and closed positions, regardless of the conveying fluid.

Abstract: A fuel injection system supplies fuel at high pressure to an internal combustion engine via at least two high-pressure fuel pumps and a high-pressure fuel distribution line. The high-pressure fuel pumps can operate in a first pump mode and a second pump mode, which differ in the amount of fuel that is pumped. A control unit alternately operates the high-pressure fuel pumps such that, during a first time period, at least one of the high-pressure fuel pumps is operated in the first pump mode and all other high-pressure fuel pumps are simultaneously operated in the second pump mode and such that, during a second time period, at least one of the high-pressure fuel pumps, which was operated in the second pump mode during the first time period, is operated in the first pump mode and the remaining high-pressure fuel pumps are simultaneously operated in the second pump mode.

Abstract: A fuel injection system supplies fuel at high pressure to an internal combustion engine via at least two high-pressure fuel pumps and a high-pressure fuel distribution line. The high-pressure fuel pumps can operate in a first pump mode and a second pump mode, which differ in the amount of fuel that is pumped. A control unit alternately operates the high-pressure fuel pumps such that, during a first time period, at least one of the high-pressure fuel pumps is operated in the first pump mode and all other high-pressure fuel pumps are simultaneously operated in the second pump mode and such that, during a second time period, at least one of the high-pressure fuel pumps, which was operated in the second pump mode during the first time period, is operated in the first pump mode and the remaining high-pressure fuel pumps are simultaneously operated in the second pump mode.

Abstract: In an arrangement for the dosed injection of a reducing agent into the exhaust tract of an internal combustion engine, comprising a pump for the pulsed pumping of the reducing agent and an atomizing injection nozzle disposed in the exhaust tract of the internal combustion engine, the injection nozzle includes a valve element which opens and closes the injection nozzle depending on the pressure generated by the pump and permits the injection of the reducing agent into the exhaust tract only when the pressure of the reducing agent is in excess of a certain value in order to ensure proper atomization of any reducing agent injected into the exhaust tract.

Abstract: A pressure limiting valve is provided which has a valve body assigned on the high-pressure side to a valve seat and an operating piston combined with the valve body to form a unit. The valve body and the operating piston are jointly spring-loaded and bound a pressure space which can be opened as a function of pressure with respect to a connection cross-section open in the return flow by way of the operating piston moving in a sliding guide.

Abstract: A fuel injector for internal combustion engines having a control valve arranged upstream of a main flow valve is configured so that the connection leading over the control chamber between the inlet and outlet, which is regulated by the valve member of the control valve, directs the function of a throttle position, among other things, by way of a limit stop of the control piston against the front wall overlapping the control chamber for the purpose of reducing control leakage.

Abstract: An injection valve for injecting fuel into the combustion chamber of an internal combustion engine has an injector needle guided inside the housing in such a way that it can be displaced longitudinally with a shaft in order to open and close the injection cross-sections. The injector needle is actuated by the fuel pressure which act upon the injector needle and by a closing spring acting in the closing direction of the injection needle. The closing spring is pre-compressed between abutments on the injector needle and the housing and is situated on the perimeter of the injector needle in the area between the injector needle guide and the valve seat. One advantage of the arrangement is the compact construction of the injection valve and the low dead volume of the control chamber on the reverse side of the injector needle.

Abstract: The invention relates to a high-pressure piston cylinder unit, especially an injection pump or an injection valve for an internal combustion engine, and to a method for producing one such high-pressure piston cylinder unit. The high-pressure piston cylinder unit has a piston which is guided inside a cylinder bore and which is coupled to an actuating element. The piston is subjected to a high pressure differential. According to the invention, fine grooves which run very close to one another are configured in at least one part of the guiding surface of the piston. The grooves ensure hydraulic pressure compensation on the periphery of the guiding surface, thus reducing wear, and prevent leakage in a longitudinal guiding direction.

Abstract: A fuel injector for an internal combustion engine includes a first injection valve having a first valve element that can be displaced in an axial direction and a first actuating device located axially downstream from the first injection valve to actuate the first injection valve. The fuel injector also has at least one second injection valve with a valve element that can be axially displaced and a second actuating device to actuate the second injection valve. The second actuating device is mounted axially downstream from the first actuating device in the valve housing, and the second actuating device to actuate the second injection valve is coupled to the latter by an actuating element, in the form of a cage-like arrangement, mounted in the valve housing in such a way that it can be displaced axially and bypasses the first actuating device.

Abstract: A high-pressure pump with a plunger reciprocating in a cylinder has a cylindrical guide surface on the plunger chamber side of the inlet/outlet port and a cylindrical guide surface on the drive side of an axial chord of 0.05 to 0.5 times the plunger diameter. This provides an advantage in that under high pump pressure the plunger emerges from the guide surface so that the plunger surface areas exposed to unilateral side forces are reduced. This prevents the plunger from canting and possibly seizing on the cylinder wall.

Abstract: A fuel injection pump having a switchable valve for the control of the start of the injection connected to the bore for the piston by a control valve bore provided axially below the filling and control bore. The control valve bore is connected with a pump pressure space via a central bore of the piston and a ring groove in an area removed from the high stress pump pressure space.

Abstract: The effective injection cross section of a fuel-injection device is varied by an adjustable shutoff element, whereby the shuttoff element is actuatable by an actuating element as a function of operating parameters of the internal-combustion engine. In the operating position, the shutoff element conducts the fuel directly to a spray hole with large cross section, but in the rest position the fuel is only conducted to the spray hole by way of a nozzle opening with a smaller cross section coaxially adjusted to the spray hole.

Abstract: A fuel-injection device in which a nozzle element is directly pressed towards the front face of a guide body for the pump plunger. The guide body is provided with an enlarged slot into which a spring element can be entered from the side, which spring element loads the valve needle of the nozzle element. Thus this injection device can be made more compact than known types and is therefore especially suitable to be used in automotive vehicles.