Cap assembly and a medicament delivery device comprising the cap assembly

1. A cap assembly comprising:

a body of a medicament delivery device, elongated along a longitudinal axis, and having a proximal and a distal end,

a cap, graspable by the hand of a user, and removably attached to the proximal end of the body, wherein the cap is rotationally locked in relation to the body characterized in that the cap assembly further comprises:

a sleeve element having a proximal and a distal part, the sleeve element being graspable by the hand of a user, the sleeve element is arranged to at least partially enclose the body, the sleeve element is arranged to be non-removably attached to the body, but able to rotate relative to the body, the sleeve element is arranged to interact with the cap such that the cap is displaced proximally in relation to the body when the sleeve element is rotated relative to the body,

wherein the cap is rotationally locked in relation to the body by engagement of at least one first guide arranged on an interior surface of the cap with at least one first guide follower arranged on an exterior surface of the proximal end of the body.

2. A cap assembly according to claim 1 wherein at least a proximal part of the sleeve element and at least a distal part of the cap form a connecting interface.

3. A cap assembly according to claim 2 , wherein at least part of the connecting interface is configured such that the cap is displaced proximally in relation to the body when the sleeve element and the cap are rotated in relation to each other.

4. A cap assembly according to claim 3 , wherein at least part of the connecting interface is shaped as a cam surface that is slanted in relation to a plane perpendicular to a longitudinal axis of the cap assembly to exert a proximally directed force on the cap when the sleeve element is rotated in relation to the cap.

5. A cap assembly according to claim 3 , wherein the sleeve element is longitudinally locked in relation to the body by engagement between: at least one second guide arranged on an interior circumferential surface of the sleeve element, and at least one second guide follower arranged on an exterior circumferential surface of the body.

6. A cap assembly according to claim 1 wherein the sleeve element is arranged to interact with the cap via the connecting interface and wherein the cap is displaced proximally in relation to the body via the connecting interface when the sleeve element is rotated from a first position to a second position in relation to the body.

7. A cap assembly according to claim 6 , wherein the sleeve element comprises a first inspection window which is arranged to be aligned with at least one corresponding second inspection window of the body when the sleeve element is in the second position in relation to the body.

8. A cap assembly according to claim 1 , wherein a first part of a lock is arranged on an inner circumferential surface of the sleeve element and a second part of the lock is arranged on an outer circumferential surface of the body, wherein the lock is arranged to lock the sleeve element in relation to the body.

9. A cap assembly according to claim 8 , wherein the lock is activated when the sleeve element is in a second position in relation to the body.

10. A cap assembly according to claim 1 , wherein at least part of an inner circumferential surface of the sleeve element and a corresponding part of an outer circumferential surface of the body comprise third guide structures arranged such that the sleeve element is displaced proximally in relation to the body, whereby the cap is displaced proximally, when the sleeve element and the body are rotated in relation to each other.

11. A cap assembly according to claim 10 , wherein the third guide structures comprise threads.

12. A medicament delivery device comprising a cap assembly according to claim 1 .

13. A cap assembly for a medicament delivery device comprising:

a body of a medicament delivery device, elongated along a longitudinal axis, and having a proximal and a distal end,

a cap, graspable by the hand of a user, and removably attached to the proximal end of the body, wherein the cap is rotationally locked in relation to the body, the cap assembly comprising:

a sleeve element having a proximal and a distal part, the sleeve element being graspable by the hand of a user, the sleeve element is arranged to at least partially enclose the body, the sleeve element is arranged to be non-removably attached to the body, but able to rotate relative to the body, the sleeve element is arranged to interact with the cap such that the cap is displaced proximally in relation to the body when the sleeve element is rotated relative to the body, wherein at least a distal part of the cap forms a connecting interface with the sleeve element,

wherein the cap is rotationally locked in relation to the body by engagement of at least one first guide arranged on an interior surface of the cap with at least one first guide follower arranged on an exterior surface of the proximal end of the body.

14. The cap assembly as claimed in claim 13 , wherein the distal part of the cap and at least a proximal part of the sleeve element forms the connecting interface.

15. The cap assembly according to claim 13

wherein the sleeve element is arranged to interact with the cap via the connecting interface.

16. The cap assembly of claim 15

wherein the cap is displaced proximally in relation to the body via the connecting interface.

17. The cap assembly of claim 16 , wherein the cap is displaced proximally in relation to the body via the connecting interface when the sleeve element is rotated from a first position to a second position in relation to the body.

18. The cap assembly according to claim 13 , wherein a first part of a lock is arranged on an inner circumferential surface of the sleeve element.

19. The cap assembly of claim 18

wherein a second part of the lock is arranged on the sleeve element to lock the sleeve element in relation to the body.