Abstract:
A piezoelectric actuator (2) for a fuel injection valve (1) has an actuator body (24) with a multiplicity of ceramic layers (26A - 26D) and a multiplicity of electrode layers (27A - 27C) which are arranged between the ceramic layers (26A - 26D). In this case, an external electrode (30) is provided which is connected to some of the electrode layers (27A, 27C). The external electrode (30) has a plurality of longitudinal wires (39A - 39C), which run in the longitudinal direction (38) of the actuator body (24), and a plurality of weft wires (37A - 37E), wherein a weft wire (37A - 37E) is passed through the longitudinal wires (39A - 39C) in such a way that some of the longitudinal wires (39A - 39C) run above the weft wire (37A - 37E) and other longitudinal wires (39A - 39C) run beneath the weft wire (37A - 37E).
Abstract:
The invention relates to a fuel injector for direct injection internal combustion engines. The fuel injector comprises an injector body (1) containing a control chamber (2).A nozzle needle/ tappet arrangement (6) in the injector body can be actuated by impinging/reducing pressure in the control chamber (2). The pressure in the control chamber (2) can be reduced via a flow channel (10), using a throttle element (13), said control chamber (2) being connected to a high pressure source by means of a permanently active pressure-side feed (28) and a second throttle element (26). A switch valve (16) is accommodated in the body (1) of the fuel injector, said valve being to connected to the control chamber (2) via the flow channel (10). In order to build up pressure in the control chamber (2), said switch valve (16) is used for parallel connection of another high-pressure side feed (29) to a third throttle element (27) in the permanently active feed (28) to the control chamber (2).
Abstract:
The invention relates to a connection (1) and a housing (2), especially a high-pressure fuel accumulator, for a fuel injection system for internal combustion engines. The connection (1) is welded. According to the invention, sealing surfaces that are physically separate from the welding seam (3) are provided between the housing (2) and the connection (1).
Abstract:
The invention relates to a valve for controlling liquids, comprising a piezo actuator (2), a mechanical translation element (3) for translating the lift of the piezo actuator (2), a return element (4) and an actuating piston (6) for actuating a valve member. The mechanical translation element (3) is located between the piezo actuator (2) and the return element (4) in the direction of actuation of the piezo actuator. The mechanical translation element (3) thus translates the lift of the piezo actuator in the direction of actuation and the return force of the return element (4) in the opposite direction.
Abstract:
The invention relates to an injection device, with an injection nozzle, a control valve (26), for opening or closing the injection nozzle, by means of a control chamber (32) and an actuator (14), for operating the control valve (26), where at least one further first valve (22) and a further second valve (24) are provided. A primary pressure may be introduced into a pressure chamber (34), for the injection nozzle, by means of the further first valve (22). The pressure chamber (34), for the injection nozzle and the control chamber (32) may be connected to an overflow system (36), by means of the further second valve. The control valve (26), the further first valve (22) and the further second valve (24) are all operable by means of the same actuator. The invention further relates to a method for the injection of fluid, in which the above device finds application.
Abstract:
A fuel pump (1) is preferably configured as an external gearwheel pump for fuel injection systems of air-compressing, self-igniting internal combustion engines. The fuel pump (1) has a housing part (3), wherein gearwheels (7, 8) are disposed in the area of said housing part (3). The housing part (3) is formed from a deep-drawn metal plate, wherein receptacles (10, 11) are provided on said housing part (3), on which said gearwheels (7, 8) are mounted.
Abstract:
A piezoelectric actuator (3) and an injector for an internal combustion engine are proposed, the electromagnetic compatibility of which is significantly improved in comparison with conventional injectors.
Abstract:
Disclosed is a fuel injection device (1) in which the injection valve (8) comprises a tubular outer valve needle (11) that coaxially surrounds an inner valve needle (20). A control chamber (35) is provided which is filled via a high-pressure fuel pipe (5) during operation while a control valve (40) is provided that is coupled to an actuator (38) in order to be actuated and is used for influencing the pressure in the control chamber (35). The upper end of the outer valve needle (11) forms a bottom border of the control chamber (35) while the raised position of the outer valve needle (11) is controlled in accordance with the pressure prevailing in the final bottom zone thereof and the pressure prevailing in the control chamber (35). The inventive fuel injection device (1) is characterized in that the control chamber (35) is directly connected to a pipe that conducts high-pressure fuel via an intake throttle (37) during operation while the control valve (40) is joined to a low-pressure zone via a first connection (51). Furthermore, a second connection (65) is joined to the control chamber (35) via a discharge throttle (throttle A) (66) while the control valve is provided with a blocked position and an open position. Finally, the inner valve needle (20) is controlled by pressure and rests against a stationary part of the device by means of a spring (28).
Abstract:
The invention relates to a fuel injector for injecting fuel into a combustion chamber of an internal combustion engine, said injector comprising at least one injection orifice (23) that can be closed or released by an injection valve member (19). The injection valve member (19) can be controlled by an actuator (2). A control piston (5) is displaceably mounted in a step-up piston (3), which is connected to the actuator (2). In said piston (5), an annular collar (18) is configured on the side facing away from the step-up piston (3). The injection valve member (19) runs through said collar in such a way that when the actuator (2) is supplied with current, the injection orifice (23) is released and when no current flows to the actuator (2), the injection orifice (23) is closed.
Abstract:
A control valve (15), for injectors in fuel injection systems for internal combustion engines is disclosed, in which a part of the control movement of the regulator (45) serves to increase the pressure in the control chamber (11). The closing times of the injector needle are thus reduced.