Needle Sheathing Device with Flexible End-Piece for Syringe

Abstract

The invention relates to a safe support device for a syringe, said support comprising a support sheath for the body of a syringe, and safety means which comprise an inner sheath suitable for sliding relative to said support sheath between a waiting retracted position, in which said inner sheath is substantially retracted inside said support sheath, and an active protection position, in which said inner sheath projects from said support sheath. The inner sheath has a free end portion formed by a flexible end-piece. The invention also relates to an assembly comprising such a safe support device and a syringe having a body, a piston and a needle disposed at one end of said body.

1 - 6 . (canceled) 
     
     
         7 . A safety syringe assembly support system for use with a syringe, the syringe comprising a distal end from which a needle distally extends, a proximal end opposite the distal end, and a piston having a proximal end comprising a head and a distal end configured to be disposed within a body of the syringe, the support system comprising:
 a first sheath having a proximal end and a distal end, the first sheath comprising at least two retaining tongues extending proximally from a tubular portion of the first sheath toward the proximal end of the first sheath; and   a second sheath configured to receive the syringe and comprising at least two activation tongues, the first sheath being disposed in the second sheath such that the at least two retaining tongues of the first sheath engage with retaining surfaces of the second sheath when the first sheath is in a start position; and   a pre-stressed spring configured to exert a biasing force on the first sheath and the second sheath when the first sheath is in the start position,   wherein the first sheath is configured to be moved distally by the biasing force of the spring relative to the second sheath from the start position to a final position, and   wherein the tubular portion of the first sheath has a diameter that allows the spring to avoid contacting the at least two retaining tongues when the first sheath and the second sheath move relative to each other from the start position to the final position,   wherein the at least two activation tongues of the second sheath are configured to cooperate with the head of the piston when the syringe is disposed in the second sheath such that when the head of the piston engages the at least two activation tongues, the at least two activation tongues are radially deflected urging the at least two retaining tongues of the first sheath to disengage from the retaining surfaces of the second sheath allowing the first sheath to move relative to the second sheath from the start position to the final position.   
     
     
         8 . The safety syringe assembly support system of  claim 7 , wherein outer surfaces of the at least two activation tongues of the second sheath are configured to contact inner surfaces of the head of the piston when the piston is advanced to deliver medicament from the syringe such that the contact between the outer surfaces of the at least two activation tongues of the second sheath and the inner surfaces of the head of the piston radially deflects the at least two activation tongues. 
     
     
         9 . The safety syringe assembly support system of  claim 8 , wherein the outer surfaces of the at least two activation tongues of the second sheath are configured to contact the inner surfaces of the head of the piston when the piston has been advanced a sufficient distance to complete a delivery of the medicament from the syringe. 
     
     
         10 . The safety syringe assembly support system of  claim 7 , wherein the at least two activation tongues of the second sheath are configured to contact free ends of the at least two retaining tongues of the first sheath when the at least two activation tongues are radially deflected by the head of the piston. 
     
     
         11 . The safety syringe assembly support system of  claim 10 , wherein the free ends of the at least two retaining tongues of the first sheath comprise ramps. 
     
     
         12 . The safety syringe assembly support system of  claim 7 , wherein the first sheath comprises a sheath body, a shoulder located proximal to the sheath body, the tubular portion located proximal to the shoulder, and the at least two retaining tongues extending proximally from the tubular portion. 
     
     
         13 . The safety syringe assembly support system of  claim 7 , wherein the pre-stressed spring is configured to exert the biasing force on a shoulder of the first sheath and a radial collar of the second sheath when the first sheath is in the start position. 
     
     
         14 . The safety syringe assembly support system of  claim 7 , wherein the first sheath comprises at least one flexible portion. 
     
     
         15 . The safety syringe assembly support system of  claim 14 , wherein the at least one flexible portion is located at the distal end of the first sheath. 
     
     
         16 . The safety syringe assembly support system of  claim 7 , wherein a distal end of the second sheath comprises a shoulder configured to abut a shoulder of the first sheath when the first sheath is in the final position. 
     
     
         17 . The safety syringe assembly support system of  claim 7 , wherein when the first sheath is in the start position and the syringe is mounted in the second sheath, the needle projects beyond a distal end of the second sheath, and wherein when the first sheath is in the final position and the syringe is mounted in the second sheath, the first sheath forms a protective shield around the needle. 
     
     
         18 . An assembly, comprising:
 a syringe, comprising:
 a syringe body having a distal end and a proximal end opposite the distal end; 
 a piston having a free proximal end and a distal end, the free proximal end of the piston having a head and the distal end of the piston disposed within the syringe body; and 
 a needle extending distally from the distal end of the syringe body; 
   a removable cap covering the needle; and   a safe support device for the syringe, the safe support device comprising:
 a first sheath having a proximal end and a distal end, the first sheath comprising at least two retaining tongues extending proximally from a tubular portion of the first sheath toward the proximal end of the first sheath; 
 a second sheath configured to receive the syringe and comprising at least two activation tongues, the first sheath being disposed in the second sheath such that the at least two retaining tongues of the first sheath engage with retaining surfaces of the second sheath when the first sheath is in a start position; and 
 a pre-stressed spring configured to exert a biasing force on the first sheath and the second sheath when the first sheath is in the start position, 
 wherein the first sheath is configured to be moved distally by the biasing force of the spring relative to the second sheath from the start position to a final position, 
 wherein the tubular portion of the first sheath has a diameter that allows the spring to avoid contacting the at least two retaining tongues when the first sheath and the second sheath move relative to each other from the start position to the final position, and 
 wherein the at least two activation tongues of the second sheath are configured to cooperate with the head of the piston when the syringe is disposed in the second sheath such that when the head of the piston engages the at least two activation tongues, the at least two activation tongues are radially deflected urging the at least two retaining tongues of the first sheath to disengage from the retaining surfaces of the second sheath allowing the first sheath to move relative to the second sheath from the start position to the final position. 
   
     
     
         19 . The assembly of  claim 18 , wherein outer surfaces of the at least two activation tongues of the second sheath are configured to contact inner surfaces of the head of the piston when the piston is advanced to deliver medicament from the syringe such that the contact between the outer surfaces of the at least two activation tongues of the second sheath and the inner surfaces of the head of the piston radially deflects the at least two activation tongues. 
     
     
         20 . The assembly of  claim 19 , wherein the outer surfaces of the at least two activation tongues of the second sheath are configured to contact the inner surfaces of the head of the piston when the piston has been advanced a sufficient distance to complete a delivery of the medicament from the syringe. 
     
     
         21 . The assembly of  claim 18 , wherein the at least two activation tongues of the second sheath are configured to contact free ends of the at least two retaining tongues of the first sheath when the at least two activation tongues are radially deflected by the head of the piston. 
     
     
         22 . The assembly of  claim 21 , wherein the free ends of the at least two retaining tongues of the first sheath comprise ramps. 
     
     
         23 . The assembly of  claim 18 , wherein the first sheath comprises a sheath body, a shoulder located proximal to the sheath body, the tubular portion located proximal to the shoulder, and the at least two retaining tongues extending proximally from the tubular portion. 
     
     
         24 . The assembly of  claim 18 , wherein the pre-stressed spring is configured to exert the biasing force on a shoulder of the first sheath and a radial collar of the second sheath when the first sheath is in the start position. 
     
     
         25 . The assembly of  claim 18 , wherein the first sheath comprises at least one flexible portion. 
     
     
         26 . The assembly of  claim 25 , wherein the at least one flexible portion is an end-piece located at the distal end of the first sheath.