Injection system and method for producing an injection system

1. An injection system for injection of fuel at a predetermined fuel pressure comprising:

an actuator, which provides a stroke for lifting an injector needle in an axial direction which opens a nozzle into which the fuel is injected;

a lever transmission facility for translating the stroke provided into a modified stroke, which lever transmission facility comprises a compensation device which is coupled to the actuator and a lever device which is coupled to the injector needle,

wherein the stroke provided by the actuator drives the compensation device in a first direction toward the injector needle;

wherein the lever device comprises at least two symmetrically-arranged single-arm levers which each contact an injector needle head of the injector needle during lifting of the injector needle, wherein each single-arm lever forms a substantially U-shaped semicircle in a plane perpendicular to the axial direction, such that the at least two single-arm levers generally form a circle in the plane perpendicular to the axial direction;

wherein the single-arm levers provide a coupling between the compensation device and the injector needle such that the single-arm levers convert a translation of the compensation device, driven by the actuator, in the first direction to a translation of the injector needle in a second, opposite direction; and

wherein the compensation device is suitable for compensating for a different force effect of the actuator on the single-arm levers.

2. The injection system according to claim 1 , wherein the actuator is embodied as a magnetic actuator or as a piezoactuator.

3. The injection system according to claim 2 , wherein the magnetic actuator has a flat armature or a plunger armature.

4. The injection system according to claim 3 , wherein the magnetic actuator with the plunger armature has an ancillary air gap.

5. The injection system according to claim 3 , wherein the magnetic actuator with the flat armature has a torus coil or a toroidal coil.

6. The injection system according to claim 1 , wherein the single-arm levers are separated from each other by means of a separation gap.

7. The injection system according to claim 2 , wherein a hydraulic compensator is provided which comprises a compensator bowl and a piston engaging in the compensator bowl, with a space being embodied between the compensator bowl and the piston which is filled with a fluid, with the space being coupled for hydraulic compensation to a compensation volume via a flow gap.

8. The injection system according to claim 7 , wherein a base plate of the piezoactuator is coupled to the compensator bowl and the compensation device comprises the piston.

9. The injection system according to claim 7 , wherein a base plate of the piezoactuator is coupled to the piston and the compensation device comprises the compensator bowl.

10. The injection system according to claim 2 , wherein the piezoactuator comprises a controllable piezo stack which, depending on a control signal, provides the stroke for actuating the injector needle in a closing direction or in an opening direction.

11. A method for manufacturing an injection system for injection of fuel at a predetermined fuel pressure comprising the following steps:

arranging an actuator in a housing of the injection system, which provides a stroke for lifting an injector needle in an axial direction which opens a nozzle into which the fuel is injected;

coupling the actuator to a lever translation facility for translating the stroke provided into a modified stroke, which lever transmission facility comprises a compensation device which is coupled to the actuator, and a lever device which is coupled to the injector needle, wherein the stroke provided by the actuator drives the compensation device in a first direction toward the injector needle, with the lever device comprising at least two symmetrically-arranged single-arm levers that each contact an injector needle head of the injector needle for lifting the injector needle, wherein each single-arm lever forms a substantially U-shaped semicircle in a plane perpendicular to the axial direction, such that the at least two single-arm levers generally form a circle in the plane perpendicular to the axial direction, and

wherein the single-arm levers provide a coupling between the compensation device and the injector needle such that the single-arm levers converts a translation of the compensation device, driven by the actuator, in the first direction to a translation of the injector needle in a second, opposite direction, and wherein the compensation device is operable to compensate for a different force effect of the actuator on the single-arm levers.

12. The method according to claim 11 , wherein the modified stroke is an increased stroke.

13. The injection system according to claim 3 , wherein the magnetic actuator with the flat armature has a torus coil or a toroidal coil, wherein the flat armature has a square cross-section.

14. The injection system according to claim 7 , wherein the fluid is the fuel.

15. A method for injection of fuel at a predetermined fuel pressure comprising the steps of:

providing a stroke by an actuator for lifting an injector needle in an axial direction which opens a nozzle into which the fuel is injected; and

translating the stroke provided into a modified stroke by a compensation device coupled to and driven by the actuator and coupled to a lever device which is coupled to the injector needle, wherein the stroke provided by the actuator drives the compensation device in a first direction toward the injector needle, wherein the lever device comprises first and second symmetrically-arranged single-arm levers which each contact an injector needle head of the injector needle during lifting of the injector needle; wherein each single-arm lever forms a substantially U-shaped semicircle in a plane perpendicular to the axial direction, such that the at least two single-arm levers generally form a circle in the plane perpendicular to the axial direction, wherein the single-arm levers provide a coupling between the compensation device and the injector needle such that the single-arm levers convert a stroke of the compensation device, driven by the actuator, in the first direction to a translation of the injector needle in a second, opposite direction;

and wherein the compensation device is suitable for compensating for a different force effect of the actuator on the single-arm levers.

16. The method according to claim 15 , comprising the step of separating the single-arm levers from each other by means of a separation gap.

17. The method according to claim 15 , comprising the step of providing a hydraulic compensator which comprises a compensator bowl and a piston engaging in the compensator bowl, with a space being embodied between the compensator bowl and the piston which is filled with the fuel, with the space being coupled for hydraulic compensation to a compensation volume via a flow gap.

18. The method according to claim 17 , comprising the step of coupling a base plate of a piezoactuator to the compensator bowl wherein the compensation device comprises the piston.

19. The method according to claim 17 , comprising the step of coupling a base plate of a piezoactuator to the piston wherein the compensation device comprises the compensator bowl.

20. The method according to claim 15 , comprising the step of providing the stroke for actuating the injector needle in a closing direction or in an opening direction by a piezoactuator comprising a controllable piezo stack controlled by a control signal.

21. The injection system according to claim 1 , wherein the at least two single-arm levers are distinct, rigid elements.