Patent ID: 7241277

Claim:
A safety device for a prefilled syringe, the syringe comprising a body, a needle carrier at one end of the body, a piston movable inside the body, and a piston rod projecting beyond the body at its end opposite from the needle carrier and suitable for pushing the piston inside the body towards the needle carrier, said device comprising a protective sheath in which the syringe body can slide between an injection position in which the syringe needle extends outside the protective sheath, and a safe position in which the needle is withdrawn inside the protective sheath, the device further comprising a resilient element suitable for acting on the syringe during the sliding of the body of the syringe inside the sheath from its injection position towards its safe position to bring the body into its safe position after injection, said resilient element having two axial ends and at least two elastically-deformable arms, each of the arms having a first axial end and a second axial end, the first axial end of each of the arms being designed to cooperate with the piston rod and being arranged in such a manner as to be capable of sliding freely along the piston rod prior to injection, the second axial end of each of the arms being arranged so as to be capable of being fixed to the protective sheath.