# US 5,704,921 A · Prefilled hypodermic syringe system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,704,921 A - Document ID: US5704921A - Status: Granted - Kind: A - Application number: 08/539,965 - Filed: 1995-10-06 - Granted: 1998-01-06 - Earliest claimed: 1995-05-17 - Inventors: Brian D. Carilli - Web page: https://patentgrep.com/patent/US5704921A ## CPC - A61M 5/322: {Retractable needles, i.e. disconnected from and withdrawn into the syringe barrel by the piston (devices for protecting guide needles in combination with catheters A61M25/0612)} - A61M 5/1782: {Devices aiding filling of syringes in situ (combination of a vial and a syringe for transferring or mixing their contents A61J1/2096, filling of medical containers in general B65B3/003)} - A61M 2005/3227: {the needle being retracted laterally outside the syringe barrel, e.g. with separate guideway} - A61M 2005/3228: {the needle being retracted by a member protruding laterally through a slot in the barrel, e.g. double-ended needles} - A61M 2005/341: {angularly adjustable or angled away from the axis of the injector} - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} ## Abstract A hypodermic syringe and method of filling the syringe with an injection fluid. The syringe includes a fluid chamber for retaining an injection fluid and a plunger assembly for expelling fluid from the chamber. The plunger assembly includes a plunger slidably disposed in the fluid chamber for creating positive pressures to cause ejection of a fluid from the chamber and an actuator coupled to the plunger for movement of the actuator between a first position with the actuator released for movement of the actuator through the fluid chamber relative to the plunger and a second position with the actuator in cooperative engagement with the plunger for driving the plunger to create the positive pressures. ## Claims ### Claim 1 An injection device for use with a needle assembly comprising: a syringe body having a fluid chamber formed therein for retaining an injection fluid, said syringe body having an outlet for dispensing fluid from said fluid chamber, and a plunger assembly including a plunger slidably disposed in said fluid chamber for creating positive pressures to cause ejection of a fluid from said fluid chamber and an actuator, said actuator being movable relative to said plunger between a first position, with at least a portion of said actuator positioned in said fluid chamber between said outlet and said plunger, and a second position, with said actuator positioned to engage said plunger and drive said plunger through said fluid chamber to create said positive pressures. ### Claim 2 (depends on 1) The injection device of claim 1 in which said actuator includes sealing means for sealing said outlet of said fluid chamber. ### Claim 3 (depends on 2) The injection device of claim 2 in which said sealing means includes a plug shaped to sealingly engage said outlet. ### Claim 4 (depends on 1) The injection device of claim 1 in which said one of said plunger and said actuator includes at least one projection and the other of said plunger and said actuator includes a socket shaped to receive said projection when said actuator is moved to said second position. ### Claim 5 (depends on 4) The injection device of claim 4 in which said projection and said socket are cooperatively shaped to substantially resist removal of said projection from said socket. ### Claim 6 (depends on 5) The injection device of claim 5 in which said projection has a maximum outer diameter and said socket has a minimum inner diameter less than said maximum outer diameter of said socket to prevent removal of said projection from said socket. ### Claim 7 (depends on 4) The injection device of claim 4 in which said actuator includes said projection and said plunger is formed with said socket. ### Claim 8 (depends on 1) The injection device of claim 1, and further comprising an injection fluid retained in said fluid chamber, said actuator extending through said injection fluid when said actuator is in said first position. ### Claim 9 (depends on 1) The injection device of claim 1, and further comprising an outer package assembly substantially enclosing said syringe body. ### Claim 10 (depends on 9) The injection device of claim 9 in which said outer package assembly is sealed to said syringe body, and further comprising a sterile gaseous substance between said syringe body and said outer package assembly. ### Claim 11 (depends on 1) The injection device of claim 1, and further comprising a needle assembly coupled to said syringe body. ### Claim 12 An injection device for use with a needle assembly comprising: a syringe body having a fluid chamber formed therein for retaining an injection fluid, said syringe body having an outlet for dispensing fluid from said fluid chamber, and a plunger assembly including a plunger slidably disposed in said fluid chamber for creating positive pressures to cause ejection of a fluid from said fluid chamber and an actuator releasably coupled to said plunger for movement of said actuator between a first position with said actuator released for movement of said actuator through said fluid chamber relative to said plunger and a second position with said actuator in cooperative engagement with said plunger for driving said plunger to create said positive pressures, said actuator including sealing means for sealing said outlet of said fluid chamber, said sealing means being movable away from said outlet for breaking said seal upon retraction of said actuator from said fluid chamber. ### Claim 13 An injection device for use with a needle assembly comprising: a syringe body having a fluid chamber formed therein for retaining an injection fluid, said syringe body having an outlet for dispensing fluid from said fluid chamber and a plunger assembly including a plunger slidably disposed in said fluid chamber for creating positive pressures to cause ejection of a fluid from said fluid chamber and an actuator releasably coupled to said plunger for movement of said actuator between a first position with said actuator released for movement of said actuator through said fluid chamber relative to said plunger and a second position with said actuator in cooperative engagement with said plunger for driving said plunger to create said positive pressures, and supply means for filling said fluid chamber with said injection fluid. ### Claim 14 (depends on 13) The injection device of claim 13 in which said supply means includes a conduit formed in said actuator, said conduit providing a passageway between the exterior of said fluid chamber to the interior of said fluid chamber between said outlet and said plunger. ### Claim 15 (depends on 13) The injection device of claim 13 in which said supply means includes a gas release passageway extending between the exterior of said fluid chamber and said fluid chamber between said outlet and said plunger for the release of gas from the interior of said fluid chamber when said fluid is injected into said fluid chamber. ### Claim 16 An injection device for use with a needle assembly comprising: a syringe body having a fluid chamber formed therein for retaining an injection fluid, said syringe body having an outlet for dispensing fluid from said fluid chamber, and a plunger assembly including a plunger slidably disposed in said fluid chamber for creating positive pressures to cause ejection of a fluid from said fluid chamber and an actuator releasably coupled to said plunger for movement Of said actuator between a first position with said actuator released for movement Of said actuator through said fluid chamber relative to said plunger and a second position with said actuator in cooperative engagement with said plunger for driving said plunger to create said positive pressures, and further comprising a needle assembly coupled to said syringe body, said needle assembly including a protective sheath mountable to said syringe body and a needle carriage slidably positioned within said sheath, said needle carriage being movable between a forward position with said needle projecting from said front end of said sheath and a retracted position with said needle positioned inside of said sheath. ### Claim 17 (depends on 16) The injection device of claim 16 in which said syringe body has a first longitudinal axis and said sheath has a second longitudinal axis spaced from said first longitudinal axis.