Injector device

1. An injector device comprising:

a housing,

a cartridge having a reservoir for medicament,

a needle unit comprising a needle, the needle unit being movably mounted to the housing, wherein prior to use of the injector device the reservoir is sealed from the needle,

an actuator configured to move the needle unit into engagement with the cartridge such that the needle is moved into fluid communication with the reservoir, and

a thread configured to cause rotation of the needle unit as the needle unit moves into engagement with the cartridge;

wherein the actuator comprises a needle sleeve that is slidably mounted to the housing such that the needle sleeve slides into the housing during use of the injector device, the needle sleeve being configured to engage the needle unit and push the needle unit into engagement with the cartridge such that the needle is moved into fluid communication with the reservoir.

2. The injector device of claim 1 , wherein the thread is disposed between the needle unit and the housing.

3. The injector device of claim 1 , wherein the thread is disposed between the needle unit and the cartridge.

4. The injector device of claim 1 , wherein the thread is arranged to couple the needle unit to the cartridge after rotation of the needle unit.

5. The injector device of claim 1 , wherein the thread is arranged to couple the needle unit to the housing after rotation of the needle unit.

6. The injector device of claim 1 , wherein the housing comprises a cartridge mounting portion that surrounds at least a part of the cartridge, and wherein the thread is arranged between the needle unit and the cartridge mounting portion.

7. The injector device of claim 6 , wherein the cartridge mounting portion comprises the thread and the needle unit comprises a thread engaging member arranged to engage the thread.

8. The injector device of claim 7 , wherein the cartridge mounting portion further comprises a groove leading into the thread, the groove being arranged such that during movement of the needle unit the needle unit moves linearly before the thread rotates the needle unit.

9. The injector device of claim 1 , wherein the needle comprises a needle axis, and the needle unit is configured to rotate about the needle axis.

10. The injector device of claim 1 , wherein the needle sleeve is configured to disengage from the needle unit after the needle unit has rotated such that the needle sleeve can move independently of the needle unit.

11. The injector device of claim 10 , wherein the needle sleeve comprises a flange that engages the needle unit, and wherein the needle unit comprises a recess arranged such that after the needle unit has been rotated the flange is aligned with the recess.

12. The injector device of claim 10 , wherein the needle sleeve comprises a helical engaging member and the needle unit comprises a protrusion that engages the helical engaging member, and wherein the helical engaging member is arranged such that rotation of the needle unit moves the protrusion out of engagement with the helical engaging member.

13. The injector device of claim 1 , wherein the needle unit comprises a protrusion and the needle sleeve comprises a groove configured to receive the protrusion in the groove such that the needle sleeve pushes the needle unit via the protrusion, wherein the groove comprises a circumferential portion to permit rotation of the needle unit relative to the needle sleeve.

14. The injector device of claim 13 , wherein the groove further comprises a movement portion arranged to permit the needle sleeve to slide into the housing after rotation of the needle unit.

15. The injector device of claim 1 , wherein the cartridge contains a medicament in the reservoir.

16. The injector device of claim 1 , wherein the thread is configured to cause rotation of the needle unit as the needle sleeve pushes the needle unit into engagement with the cartridge.