| 主权项 |
1. A needle assembly for connection to an injection pen having a boss with external threads for receiving the needle assembly, comprising:
a sleeve supporting internally a double-ended needle to extend axially of the sleeve, said needle having an injection end and a non-injection end and the sleeve having a radially deformable end provided with at least one internal profile for radial interengagement with the threads of the pen boss such that with full radial inter-engagement the sleeve is securely connected to the injection pen, the needle being orientated with the non-injection end directed towards said deformable end so that on connection of the sleeve to an injection pen, the non-injection end of the needle penetrates a drug reservoir within the pen; a collar mounted around the sleeve for sliding movement between a first position adjacent the deformable end at which the collar maintains full radial inter-engagement of the profile with the threads of the boss and a second position where the collar is displaced from said end so that radial deformation of said end allows radial disengagement of the profile from the threads whereby the needle assembly may be pulled axially from the boss. |
