Patent ID: 6193695
Filing Date: 2001-02-27
Classification: A61M

Abstract:
An improved syringe assembly, comprising:a cylinder body having a needle end and a seal cap end, the cylinder body having a central axis and an internal through bore extending between the needle end and the seal cap end;a retainer adjacent the needle end of the cylinder body;a needle assembly including a hypodermic needle and needle support, the needle support being in scaled engagement with the needle and releasably retaining the needle assembly in sealed engagement with the cylinder body by the retainer;a piston assembly having a needle end and a seal cap end and including a piston for coaxial telescopic movement of the piston assembly within the internal through bore, and one or more piston seals for effecting a pneumatic seal between the piston and an inner wall of the cylinder body;a connector for selectively attaching the piston assembly to the needle assembly;a piston stem having a piston end and a handle end with the piston end attached to the piston assembly for axially moving the piston assembly within the through bore of the cylinder body;a handle attached to the handle end of the piston stem;a seal cap assembly attached to the seal cap end of the cylinder body, the seal cap assembly including a seal cap having a piston side and a stem handle side, the seal cap being in pneumatic sealing engagement with the seal cap end of the cylinder body for effecting a pneumatically sealed chamber inside of the cylinder body between the piston assembly and the seal cap assembly, the seal cap assembly including a port for telescopic movement of the piston stem through the port, and including a seal for effecting a pneumatic seal between the seal cap and the piston stem; anda one-way valve for evacuation of air from within the internal through bore between the piston assembly and the seal cap assembly while prohibiting the entry of air into the internal through bore of the cylinder body.