Needleless syringe

• Main Authors: PATEL DAHYABHAI R, KAY JOHN MICHAEL
• Format: Patent
• Language: English
• Published: 03.04.2001
• Edition: 7
• Subjects: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROMTHE BODY; HUMAN NECESSITIES; HYGIENE; MEDICAL OR VETERINARY SCIENCE

A single use needless syringe for administering a fluid medication. The syringe comprises a hollow, tubular body which includes a gas storage portion defining a storage chamber containing a quantity of pressurized gas. The body also includes an ejector portion defining a piston chamber which is selectively placeable into fluid communication with the storage chamber and has a piston movably disposed therein. In addition to the gas storage and ejector portions, the body has a barrel portion defining a delivery chamber for receiving a prescribed dosage of the fluid medication, with the delivery chamber being oriented relative to the piston chamber such that the piston is advanceable into the delivery chamber. A discharge orifice of the body fluidly communicates with the delivery chamber and allows the fluid medication to be filled thereinto and expelled therefrom. The syringe further comprises a fracturable release member which is disposed within the body and normally prevents the flow of the compressed gas from the storage chamber into the piston chamber. Removably attachable to the body is a trigger mechanism of the syringe which includes a stem portion partially insertable into the body and engagable to the release member, and a head portion attached to the stem portion. The application of compressive pressure to the head portion subsequent to the insertion of the stem portion into the body facilitates the fracture of the release member and resultant flow of the pressurized gas into the piston chamber. The compressed gas acts against the piston in a manner forcing the piston into the delivery chamber which causes the fluid medication to be expelled therefrom via the discharge orifice.