Fuel filler cap

1. A tank closure, comprising:

a first tank closure member having a first stop member;

a second tank closure member flexibly mounted in an axial direction relative to the first tank closure member, the second tank closure member having a second stop member; and

a bias member having a spring force to engage the second tank closure against the first tank closure member,

wherein the second stop member, in a closed position of the tank closure, forms a mechanical stop that comes into contact with the first stop member to prevent axial lift off of the second tank closure member from the first tank closure member against the spring force of the bias member.

2. The tank closure of claim 1 , wherein the second tank closure member is rotatably moveable relative to the first tank closure member to the closed position as far as an end position.

3. The tank closure of claim 2 , wherein the second stop member, before reaching the end position, does not form a stop relative to the first stop member.

4. The tank closure of claim 2 , wherein the second stop member forms a stop relative to the first stop member upon reaching the end position.

5. The tank closure of claim 1 , wherein the second tank closure member has a seal member configured such that, in the closed position of the tank closure, is axially pressed by the bias member in a direction towards the first tank closure member.

6. The tank closure of claim 1 , wherein:

the second stop member comprises at least one locking bar, and

the first stop member comprises at least one bearing surface to be engaged by the locking bar.

7. The tank closure of claim 6 , wherein the first tank closure member comprises a rotatable tank closure component which rotates concurrently with the second tank closure member.

8. The tank closure of claim 7 , wherein the first tank closure member comprises a non-rotatable tank closure component which remains stationary during the rotation of the second tank closure member.

9. The tank closure of claim 8 , wherein the non-rotatable tank closure component is configured to engage a tank filler neck to secure a position of the non-rotatable tank closure component in a peripheral direction.

10. The tank closure of claim 8 , wherein the at least one bearing surface of the first stop member is arranged on the non-rotatable tank closure component.

11. The tank closure of claim 8 , wherein the non-rotatable tank closure component comprises a ramp member.

12. The tank closure of claim 11 , wherein an extension of the rotatable tank closure component is located at a distal end of the ramp member in order to adopt the end position.

13. The tank closure of claim 6 , wherein the rotatable tank closure component is caused to move by the rotation of the second tank closure member via the locking bar of the second tank closure member in a manner that causes the rotatable tank closure component to rotate concurrently with the second tank closure member.

14. A tank closure, comprising:

a first tank closure member including a rotatable tank closure component, a non-rotatable tank closure component, and a first stop member having at least one bearing surface;

a second tank closure member mounted for rotation relative to the first tank closure member to a closed position, the second tank closure member having a second stop member configured to rotate concurrently with the rotatable tank closure component, and at least one locking bar configured to engage the at least one bearing surface, wherein the non-rotatable tank closure component is configured to remain stationary during the rotation of the second tank closure member; and

a bias member having a spring force to engage the second tank closure against the first tank closure member,

wherein the second stop member, in the closed position of the second tank closure member, forms a mechanical stop that comes into contact with the first stop member to prevent axial lift off of the second tank closure member from the first tank closure member against the spring force of the bias member.

15. The tank closure of claim 14 , wherein the non-rotatable tank closure component is configured to engage a tank filler neck to secure a position of the non-rotatable tank closure component in a peripheral direction.

16. The tank closure of claim 14 , wherein the at least one bearing surface of the first stop member is arranged on the non-rotatable tank closure component.

17. The tank closure of claim 15 , wherein the non-rotatable tank closure component comprises a ramp member.

18. The tank closure of claim 15 , wherein the rotatable tank closure component is caused to move by the rotation of the second tank closure member via the locking bar of the second tank closure member in a manner that causes the rotatable tank closure component to rotate concurrently with the second tank closure member.

19. A tank closure, comprising:

a first tank closure member having a pair of first stop members arranged offset so as to oppose one another;

a second tank closure member flexibly mounted in an axial direction relative to the first tank closure member, the second tank closure member having a pair of second stop members configured such that, in a closed position of the tank closure, form a mechanical stop that comes into contact with the first stop member which prevents axial lift off of the second tank closure member from the first tank closure member; and

a bias member having a spring force to engage the second tank closure against the first tank closure member,

wherein the pair of second stop members prevent the axial lift off of the second tank closure member from the first tank closure member against the spring force of the bias member.