Abstract: A safety syringe 10 includes a generally tubular body 14 having a needle end 18 and plunger end 22, needle 38 and retractable needle seat 30, two-way valve 36, plunger 42, stopper 62, piston 52, and rear plunger seal 44. During use, the plunger may be moved to create a vacuum in the plunger. The user then moves the plunger toward the needle end, pressurizing a vial, then pulls backward to a selected position corresponding to the desired volume of fluid to be withdrawn. At the conclusion of the injection stroke, the piston is disengaged from the plunger. The vacuum within the plunger retracts the needle safely into the tubular body.

Abstract: The blood sampling assembly includes a retractable double-ended needle so that a vial may be passed through an opposed end of the needle to obtain a blood sample. The assembly includes a hollow cylinder including circumferentially spaced seat tabs which allow a needle seat and the needle supported thereon to be released upon rotation of tube with respect to hollow cylinder. The extractor assembly includes a stopper for maintaining a vacuum within tube to withdraw the needle to a retracted position within the tube upon rotation of the tube, the end cap, and the stopper retainer. A stopper tab positioner rotationally connects the stopper to the cylinder.

Abstract: A disposable syringe assembly 10 including a cylinder body 12, a needle assembly 14, a piston assembly 16, a rear seal assembly 18, a hollow shaft 20, and a valve assembly having a valve port 61 and valve seals 49. The needle assembly may be releasably engaged with the cylinder body. The body and the piston assembly moveable within the body may define each of a fluid chamber 74 and an annular chamber 28. As fluid is drawn into the fluid chamber by movement of the piston assembly, air may be displaced from the annular chamber through the valve assembly. As fluid is discharged from the fluid chamber, the valve assembly may be closed and a vacuum created in the annular chamber. A valve positioner may control connector connectivity and valve port position. Near the end of the fluid discharge piston stroke, a connector 88 engaged with either the shaft of with the piston assembly may engage selectively engage a mating connector on the needle assembly. The needle assembly may be disengaged from the body.