Throttle device for controlling an amount of fuel to be supplied to a fuel injection nozzle, as well as an injection device

1. A throttle device for controlling a fuel quantity to be supplied to a fuel injection nozzle, the throttle device comprising:

a control chamber for collecting the fuel; and

a supply device for supplying the fuel to said control chamber in a main flow direction;

said supply device having an inlet throttle for reducing a pressure of the fuel in said main flow direction, said inlet throttle having a length, and said length of said inlet throttle being selected to cause a fuel flowing through said inlet throttle during operation to flow through said inlet throttle in a turbulent flow, said length of said inlet throttle lying in a length range from 0.4 mm to 0.5 mm and said inlet throttle having a diameter lying in a diameter range from 171 μm to 176; and

a discharge device for discharging the fuel from said control chamber, said discharge device discharging the fuel from said control chamber in a discharge flow direction being opposite to said main flow direction of the fuel in said supply device.

2. The throttle device according to claim 1 , wherein said length of said inlet throttle lies in a length range from 0.1 mm to 0.5 mm.

3. The throttle device according to claim 1 , wherein said length of said inlet throttle lies in a length range from 0.15 mm to 0.4 mm.

4. The throttle device according to claim 1 , wherein said length of said inlet throttle lies in a length range from 0.2 mm to 0.3 mm.

5. The throttle device according to claim 1 , wherein said inlet throttle has a diameter being reduced proportionally to a reduction of said length of said inlet throttle.

6. The throttle device according to claim 1 , wherein said inlet throttle is a non-cavitating throttle.

7. An injection device for injecting fuel into a combustion chamber, the injection device comprising:

a fuel injection nozzle for injecting the fuel into the combustion chamber; and

a throttle device according to claim 1 for controlling a fuel quantity to be supplied to said fuel injection nozzle during operation.

8. The injection device according to claim 7 , which further comprises:

a housing having an upper region and a lower region;

said fuel injection nozzle and said throttle device being disposed in said lower region;

a discharge device for discharging the fuel from said control chamber, said discharge device having a valve; and an actuator device for actuating said valve of said discharge device, said actuator device having a piezo stack disposed together with said throttle device and said fuel injection nozzle in said lower region of said housing in a direct vicinity of said throttle device, for introducing waste heat from said piezo stack into said throttle device during operation.

9. A throttle device for controlling a fuel quantity to be supplied to a fuel injection nozzle, the throttle device comprising:

a control chamber for collecting the fuel; and

a supply device for supplying the fuel to said control chamber in a main flow direction;

said supply device having an inlet throttle for reducing a pressure of the fuel in said main flow direction, said inlet throttle having a length, and said length of said inlet throttle being selected to cause a fuel flowing through said inlet throttle during operation to flow through said inlet throttle in a turbulent flow said length of said inlet throttle lying in a length range from 0.2 mm to 0.3 mm and said inlet throttle having a diameter lying in a diameter range from 166 μm to 170 μm ; and

a discharge device for discharging the fuel from said control chamber, said discharge device discharging the fuel from said control chamber in a discharge flow direction being opposite to said main flow direction of the fuel in said supply device.

10. The throttle device for controlling a fuel quantity to be supplied to a fuel injection nozzle, the throttle device comprising:

a control chamber for collecting the fuel; and

a supply device for supplying the fuel to said control chamber in a main flow direction;

said supply device having an inlet throttle for reducing a pressure of the fuel in said main flow direction, said inlet throttle having a length, and said length of said inlet throttle being selected to cause a fuel flowing through said inlet throttle during operation to flow through said inlet throttle in a turbulent flow;

a discharge device for discharging the fuel from said control chamber, said discharge device discharging the fuel from said control chamber in a discharge flow direction being opposite to said main flow direction of the fuel in said supply device;

said discharge device has an outlet throttle for reducing a pressure of the fuel in said discharge flow direction;

said discharge device has an outflow region disposed upstream of said outlet throttle in said discharge flow direction;

said discharge flow direction has an axis in said outflow region; and

said outlet throttle has a longitudinal axis being inclined relative to said axis of said discharge flow direction in said outflow region.

11. The throttle device according to claim 10 , wherein said longitudinal axis and said axis of said discharge flow direction of the fuel in said outflow region define an angle of inclination there between being less than 50°.

12. The throttle device according to claim 10 , wherein said longitudinal axis and said axis of said discharge flow direction of the fuel in said outflow region define an angle of inclination there between being less than 45°.

13. The throttle device according to claim 10 , wherein said outlet throttle is a cavitating throttle.

14. The throttle device according to claim 10 , wherein said inlet throttle is a non-cavitating throttle and said outlet throttle is a cavitating throttle.