Embodiments of the invention are directed to flush syringe assemblies comprising an integrated contamination-prevention device integrated with device connector flushing positioned so that the practitioner cannot forget to apply disinfectant. The flush syringe assemblies comprise a barrel with an elongate plunger rod disposed therein and a cap comprising a passageway. The plunger rod includes a stopper of which at least a portion can be embedded in the passageway of the cap to form a plug in the cap. Methods of flushing a vascular access device (VAD) while providing a flush syringe assembly described herein are also disclosed.

Embodiments of the invention are directed to flush syringe assemblies comprising an integrated contamination-prevention device integrated with device connector flushing positioned so that the practitioner cannot forget to apply disinfectant. The flush syringe assemblies comprise a barrel with an elongate plunger rod disposed therein and a cap comprising a passageway. The plunger rod includes a stopper of which at least a portion can be embedded in the passageway of the cap to form a plug in the cap. Methods of flushing a vascular access device (VAD) while providing a flush syringe assembly described herein are also disclosed.

A syringe with plunger reaction pressure reduction structure is proposed. The syringe includes: a barrel including a finger grip at a rear end thereof and a Luer-lock connector in which a thread portion is formed on an inner surface outside a tapered tube of a front discharge end thereof; a plunger rod configured to be inserted in an inside of the barrel and including a push end at a rear end thereof; a plunger coupled to a front end of the plunger rod; and a needle hub configured to be screwed with the Luer-lock connector and including an injection needle mounted to a front end thereof. The syringe is configured to have a three-step structure at the plunger in which intervals between steps are gradually shortened, so that the reaction pressure applied to the plunger is distributed and the injection is easily performed.

A syringe with plunger reaction pressure reduction structure is proposed. The syringe includes: a barrel including a finger grip at a rear end thereof and a Luer-lock connector in which a thread portion is formed on an inner surface outside a tapered tube of a front discharge end thereof; a plunger rod configured to be inserted in an inside of the barrel and including a push end at a rear end thereof; a plunger coupled to a front end of the plunger rod; and a needle hub configured to be screwed with the Luer-lock connector and including an injection needle mounted to a front end thereof. The syringe is configured to have a three-step structure at the plunger in which intervals between steps are gradually shortened, so that the reaction pressure applied to the plunger is distributed and the injection is easily performed.

A plunger rod for use in a syringe barrel for driving a bung through the syringe barrel to expel a substance therefrom, the plunger rod including: a bung fixing configured to be received within a recess of a bung and including at least one laterally extending lug including a thread engagement surface configured to engage with a point on a track portion of a thread on a sidewall of the recess, wherein the lug is further configured to cross the thread on relative rotation between the plunger rod and the bung under a force applied by a user, such that the thread engagement surface of the lug engages the point of the track portion every full rotation of the syringe plunger relative to the bung.

An I.V. flush syringe assembly includes a barrel having an inside surface defining a chamber for retaining fluid, an open proximal end and a distal end with a passageway therethrough in fluid communication with the chamber. An elongate plunger having a proximal end, a distal end and a flexible stopper is slidably positioned in fluid-tight engagement with the inside surface of the barrel for drawing fluid into and out of the chamber by movement of the stopper relative to the barrel. The barrel includes anti-reflux structure for holding said stopper in a partially deflected position after fluid has been delivered from the chamber and the stopper is being force against the distal end of the chamber.

Embodiments of the invention are directed to flush syringe assemblies comprising an integrated contamination-prevention device integrated with device connector flushing positioned so that the practitioner cannot forget to apply disinfectant. The flush syringe assemblies comprise a barrel with an elongate plunger rod disposed therein and a cap comprising a passageway. The plunger rod includes a stopper of which at least a portion can be embedded in the passageway of the cap to form a plug in the cap. Methods of flushing a vascular access device (VAD) while providing a flush syringe assembly described herein are also disclosed.

A syringe system, piston seal systems, stopper systems, and methods for assembling and using the syringe systems. The piston seal system including a piston seal member and a piston head member. The injection system including a container, a piston seal system positioned within the container, and a stopper system coupled to an end of the container. The method of assembling an injection system, the method includes obtaining a container, a piston seal system, and a stopper system. The method also includes inserting the piston seal system into a cavity within the container. The method further includes securing the stopper system at an end of the container in an opening of the cavity. Methods of using the syringe system, piston seal systems, and stopper systems are also disclosed.

Embodiments of the invention are directed to flush syringe assemblies comprising an integrated contamination-prevention device integrated with device connector flushing positioned so that the practitioner cannot forget to apply disinfectant. The flush syringe assemblies comprise a barrel with an elongate plunger rod disposed therein and a cap comprising a passageway. The plunger rod includes a stopper of which at least a portion can be embedded in the passageway of the cap to form a plug in the cap.

A method and apparatus for use in controlling a dispensing rate of medication or other substance via a syringe, including, without limitation, into a patient, intravenous line port or heparin lock. A force (typically manual) is applied to an input plunger of a dashpot, which is directly coupled to a piston which, in turn, is coupled to an output plunger. The force applied to the input plunger is buffered and transmitted to the output plunger. The output plunger acts upon the plunger of a conventional syringe, thereby resulting in flow of medicine or any other substance from the syringe at a desired and controlled flow rate.