Fuel connection unit

1. A fuel-operated vehicle heater comprising: a heater housing having a fuel connection unit receiving opening; and a fuel connection unit connected to the heater housing, the fuel connection unit comprising: a connection unit body inserted into the fuel connection unit receiving opening of the heater housing, and surrounded by a sealing element clamped between an outer circumference of the connection unit body and the heater housing, a fuel flow volume being provided in the connection unit body; a fuel release line connection area configured as a pipe branch and projecting from the connection unit body on a side of the connection unit body facing an interior of the heater housing, the fuel release line connection area providing a fuel duct open towards the fuel flow volume in the connection unit body; a fuel release line connected to the fuel release line connection area and leading to a combustion chamber; a fuel feed line connection area configured as a pipe branch and projecting from the connection unit body on a side of the connection unit body facing outwards for connecting a fuel feed line, the fuel feed line connection area providing a fuel duct open towards the fuel flow volume in the connection unit body; and at least one functional unit for influencing a flow of fuel in the fuel flow volume, the at least one flow influencing means being provided in the connection unit body.

2. The fuel-operated vehicle heater in accordance with claim 1 , wherein the at least one flow influencing means comprises a pulsation damper.

3. The fuel-operated vehicle heater in accordance with claim 2 , wherein the pulsation damper comprises a pressure equalization volume and a flexible separating element separating the pressure equalization volume from the fuel flow volume.

4. The fuel-operated vehicle heater in accordance with claim 3 , wherein:

the pulsation damper further comprises a pulsation damper body providing the pressure equalization volume;

the flexible separating element is fixed at the pulsation damper body such that the flexible separating element closes the pressure equalization volume.

5. The fuel-operated vehicle heater in accordance with claim 3 , wherein a damper mounting recess receiving the pulsation damper is formed in the connection unit body.

6. The fuel-operated vehicle heater in accordance with claim 1 , wherein the at least one flow influencing means comprises a fuel valve.

7. The fuel-operated vehicle heater in accordance with claim 6 , wherein the fuel valve comprises a nonreturn valve blocking the fuel connection unit against flow in a direction from the fuel release line connection area to the fuel feed line connection area.

8. The fuel-operated vehicle heater in accordance with claim 7 , wherein the nonreturn valve comprises:

a second connection unit body part with a valve seat;

a prestressing element supported at a first connection unit body part; and

a valve element pressed by the prestressing element against the valve seat.

9. The fuel-operated vehicle heater in accordance with claim 6 , wherein the fuel valve comprises an on-off valve, which can be actuated for releasing and blocking a flow path from the fuel feed line connection area to the fuel release line connection area.

10. The fuel-operated vehicle heater in accordance with claim 1 , wherein the at least one flow influencing means comprises a fuel pump.

11. The fuel-operated vehicle heater in accordance with claim 10 , wherein the fuel pump comprises a pumping element movable to and fro for delivery of fuel and an electrically excitable drive unit associated with the pumping element.

12. The fuel-operated vehicle heater in accordance with claim 11 , wherein the drive unit comprises:

an electromagnet unit carried stationarily at the connection unit body;

a pump piston movable linearly to and fro in a pump chamber; and

an armature provided at the pump piston for the magnetic interaction with the electromagnet unit, wherein the pump piston is moveable, by electrical excitation of the electromagnet unit, in a direction in which fuel is discharged from the pump chamber and the armature is moveable by a prestressing element in a direction in which fuel is received in the pump chamber.

13. The fuel-operated vehicle heater in accordance with claim 1 , wherein the at least one flow influencing means comprises a fuel filter.

14. The fuel-operated vehicle heater in accordance with claim 1 , wherein the fuel feed line connection area and the fuel release line connection area are arranged flush with one another.

15. The fuel-operated vehicle heater in accordance with claim 1 , wherein the connection unit body is disk-shaped.