Coupling arrangement and connection assembly

1. A coupling arrangement comprising:

a housing comprising a first locking part,

a connecting element comprising a pin, and

a locking element separate from said housing and said connecting element for coupling of the same, wherein the locking element is cylindrical having a center axis comprising:

a second locking part, and

at least one locking contour having a first end designed to take in the pin of the connecting element to disable rotational movement of the connecting element via positive locking, and

a ring, which is arranged intermediate the locking element and the housing,

wherein the ring, the first locking part and the second locking part being designed and arranged such as to form a positive locking at least in one direction of the center axis between the housing and the locking element via the ring.

2. The coupling arrangement according to claim 1 , wherein the first locking part of the housing comprises a first protrusion designed to form a first area of contact for the ring.

3. The coupling arrangement according to claim 1 , wherein the first locking part of the housing comprises a first groove designed to at least partly take, in the ring.

4. The coupling arrangement according to claim 1 , wherein at a first axial end of the first groove the housing is having a larger outer diameter than at a second axial end of the first groove.

5. The coupling arrangement according to claim 1 , wherein the second locking part of the locking element comprises a second protrusion designed to form a second area of contact for the ring.

6. The coupling arrangement according to claim 1 , wherein the second locking part of the locking element comprises a second groove designed to at least partly take in the ring.

7. The coupling arrangement according to claim 1 , wherein at a first axial end of the second groove the locking element is having a larger inner diameter than at a second axial end of the second groove.

8. The coupling arrangement according to claim 1 , wherein the locking element comprises two side portions connected through an intermediate portion, the first side portion having a larger inner diameter than the second side portion with the first side portion comprising the locking contour and the second side portion comprising the second locking part.

9. The coupling arrangement according to claim 1 , wherein at least one of the outer diameter of the housing at the first axial end of the first groove and the diameter of the housing at the second axial end of the first groove is smaller than the inner diameter of the locking element.

10. The coupling arrangement according to claim 1 , wherein at least one of the outer diameter of the housing at the first protrusion and at the part of the housing along the center axis extending away from the first area of contact is smaller than the inner diameter of the locking element.

11. The coupling arrangement according to claim 1 , wherein the ring is fixed to at least one of the first protrusion and the first groove of the housing.

12. A connection assembly for connecting an injector to a fluid supply comprising a coupling arrangement comprising:

a housing comprising a first locking part,

a connecting element comprising a pin, and

a locking element which is cylindrical having a center axis and arranged between the housing and the connecting element, comprising:

a second locking part,

at least one locking contour having a first end designed to take in the pin of the connecting element to disable rotational movement of the connecting element around the center axis via positive locking, and

a ring, which is arranged intermediate the locking element and the housing,

wherein the ring, the first locking part and the second locking part being designed and arranged such as to form a positive locking at least in one direction of the center axis between the housing and the locking element via the ring,

wherein the housing forms part of the injector, and wherein the connecting element, which is fixed to a pipe of the fluid supply, communicates with the pipe through a fluid recess at a first axial end area of the connecting element.

13. The connection assembly according to claim 12 , wherein the respective locking contour of the locking element and the respective pin of the connecting element being designed and arranged such as to form a positive locking at least in one direction of the center axis between the locking element and the connecting element.

14. The connection assembly according to claim 12 , comprising three pins of the connecting element and three locking contours of the locking element each having the first end designed to take in the respective pin of the connecting element to disable rotational movement of the connecting element via positive locking.

15. The connection assembly according to claim 12 , comprising an outer spring, which is arranged intermediate the pipe and the locking element, the outer spring being designed and arranged such as to force the locking element away from the pipe.

16. The connection assembly according to claim 12 , comprising an inner spring, which is arranged in the connecting element having a smaller diameter than the outer spring, the inner spring being designed and arranged such as to force the housing of the injector away from the pipe.

17. The connection assembly according to claim 12 , wherein the first locking part of the housing comprises a first protrusion designed to form a first area of contact for the ring.

18. The connection assembly according to claim 12 , wherein the first locking part of the housing comprises a first groove designed to at least partly take in the ring.

19. The connection assembly according to claim 12 , wherein at a first axial end of the first groove the housing is having a larger outer diameter than at a second axial end of the first groove.

20. The connection assembly according to claim 12 , wherein the second locking part of the locking element comprises a second protrusion designed to form a second area of contact for the ring.