Patent ID: 7637890

Claim:
A safety syringe comprising a hollow tube with a front end, an inside, and an inside wall, a plunger, with a tip end adapted to fit into said inside of said hollow tube, a rubber piston attached on said tip end of said plunger, a needle holder attached to said front end of said hollow tube, a locating ring-groove formed on said inside wall near said front end of said hollow tube for catching said needle holder, and one or more O-ring attached between said needle holder and said inside of said hollow tube; wherein said plunger comprises a conical head on the front end thereof, which is formed with a barb in the middle portion of said conical head, said needle holder further comprises a cone base, with a hollow inside, an inner wall and an outside bottom wall, further comprising a Roll cone for fitting into a needle, and a seat, with an internal front end and an outside front end, adapted to fit into said hollow inside of said cone base, wherein said cone base further comprises a circular base for fitting into said inside of said hollow tube, an internal convex edge formed on said inner wall of said cone base, and several elastic catching lugs formed on said outside bottom wall of said cone base, adapted to engage with said locating ring-groove of said hollow tube, and said seat further comprises an elastic clamper formed on said internal front end of said seat, a front flange formed on said outside front end of said seat and adapted to get over said internal convex edge of said cone base during assembly and to engage with said internal convex edge after assembly, and a middle flange formed on the middle portion of said seat for supporting outwards said elastic catching lugs of said cone base.