The invention relates to a safety device for avoiding stabbing injuries, for a syringe having a syringe body and a piercing means arranged on the distal end of said syringe body. The safety device comprises a sleeve element that extends in an axial direction (X) and encloses at least partly the piercing means and the syringe body, and a collar element that is arranged on a distal end region of the syringe body and locks the safety device in the axial direction (X), said collar element having at least one guide projection which is guided in at least one guide track of the sleeve element during a movement of the syringe body relative to the sleeve element substantially in the axial direction. The safety device is characterised in that the collar element is arranged on the distal end region of the syringe body so as to be rotatable in a circumferential direction (U) and has at least one tolerance compensating element which is in operative contact, mechanically, with the syringe body so that tolerances of the syringe body can be compensated for.

The disclosure pertains to a safety syringe having a retractable needle shield which is capable of being retracted to expose the needle for use; being advanced to a needle shielding position; and, if desired, of being removed from the syringe with the shielded needle safely contained within the retractable needle shield via a frangible segment between the syringe barrel and the needle/needle shield components. The disclosure further pertains to a method of using the safety syringe having a retractable needle shield.

A needle assembly for an injection pen (22) has a sleeve (21) supporting internally a double-ended needle having an injection end and a non-injection end (25). The end of the sleeve surrounding the non-injection end (25) of the needle is divided into deformable segments (28) and is internally threaded for interengagement with a threaded boss (23) of the injection pen (22). A collar (29) is mounted on the sleeve (21) for sliding movement between a first position where the collar (29) overlies the segmented end and maintains interengagement of the threads at that end with those of the injection pen boss (23) and a second position where the segments may expand radially to come free of the injection pen boss (23). The needle may be mounted on a carrier (68) slidable with respect to the sleeve (21), the carrier (68) being coupled to the sleeve (21) for movement thereby.

The safety needle assembly comprises a needle/cannula (112) mounted in a tubular housing (120). The needle has a patient end (114) and a non-patient end and an aim of the invention is to provide passive needle stick protection at the non-patient end. A further aim is to increase the reliability and to reduce fatigue on the spring means prior to use. The cannula (112) is located within the needle mount (160) which is located within the tubular housing (120). The shielding sleeve (130) provides the blocking means which retains the alignment of the cannula (110) along the longitudinal axis of the tubular member (120). In particular, the blocking means is arranged to counteract the pivoting force of the spring or an ability of the cannula to freely rotate in order to retain the cannula (112) in an operative position. In the present invention, the spring (170) and the needle mount (160) are arranged at a set position and the use of the safety needle assembly (110) with the medical injector (111) causes a shift from the set position. This shift enables the spring (170) to then rotate the needle (112) to the shielding position when the safety needle assembly (110) is detached from the medical injector (111).