Patent ID: 6110147
Filing Date: 2000-08-29
Classification: A61M

Abstract:
In an injection syringe (10; 100) of the type including, on the one hand, an elongate syringe body (12; 112) comprising a tube (16; 116) and a front wall (20; 118) equipped with an injection needle (22; 120), and, on the other hand, a rear actuating plunger (14; 114) mounted so as to be displaceable inside the tube (16; 116), the improvement wherein:said syringe is equipped with a mobile needle protector (36, 140) which is displaceable in relation to the body (12; 112), under the effect of the actuating plunger (14; 114) being actuated and driven into the body (12; 112), and during this actuation, between a retracted position, set back from the injection end (22A; 120A) of the needle (22; 120), and an active protection position, in which the front end of the protector is situated in front of the injection end (22A; 120A) of the needle (22; 120);the body (12) includes at least one opening (34) for the passage of the protector (36), of which a rear end (44), situated inside the syringe body (12), forms a surface for actuation by the rear plunger (14) for forward displacement of the protector (36);the injection needle (22) protrudes inside the syringe body (12), and the inside of the tube (16) is provided with a mobile front plunger (62) interposed between the protector (36) and the rear actuating plunger (14), the two plungers delimiting a space for fluid (60) which is to be injected;prior to use of the syringe, the front plunger (62) is arranged behind the needle (22), and the front plunger (62) is designed to be punctured by the proximal end (22B) of the needle (22) when the rear plunger (14) is driven in; andthe protector (36) and the body (12) include complementary means (42, 64) for temporarily maintaining the protector (36) in its retracted position, said means being designed to withstand thrust exerted by the front plunger (62) on the protector (36) when the rear plunger (14) is being driven into the tube (16), while the rear plunger (14) is behind the proximal end (22B) of the needle (22) or the front plunger (62).