A system for injecting includes a cartridge body defining a proximal opening and a distal needle interface. The system also includes a plunger member defining a plunger interior and configured to be manually manipulated to insert a stopper member relative to the cartridge body. The plunger member includes a needle retention feature disposed in the plunger interior, an energy-storage member disposed in the plunger interior, and an energy-storage member latching member disposed in the plunger interior. The system further includes a needle hub assembly coupled to the distal needle interface of the cartridge body. The needle assembly includes a needle having a needle proximal end feature, a hub, and a needle latching member configured to couple the needle to the hub. The needle is retractable into plunger interior upon manipulation of the plunger member to actuate the energy-storage member latching member.

A safety syringe has at least two angled lock extensions on opposing sides of a plunger shaft. A plunger tip integral with the shaft has at least a pair of locking lugs. A syringe barrel has a needle assembly housing end securing the needle assembly in place for injections. The needle assembly has a needle secured in a needle housing and at least two locking ledges formed as an integral part. The end cap further comprises an opening sized to receive the shaft to fit and move back and forth, and at least two locking edges. The locking edges engage with the angled lock extensions to lock the plunger in place when fully withdrawn. The locking ledges on the needle housing engage with the locking lugs when the plunger tip is pushed into the needle housing, so as to use to retract the needle into the barrel.

A barrel adapter for a syringe having a barrel and plunger. The adapter comprises a barrel tip and a needle retraction mechanism having a needle subassembly with a needle and a lumen, actuator subassembly, and biasing member. The needle subassembly moves from an injection to a retracted position within the barrel tip. The actuator subassembly includes a retainer connected to the barrel tip, a stylet held in a stylet disc, and a prong passing into the retainer. The stylet slides within the needle lumen and is spaced from the needle tip in the injection position. The biasing member biases the NOM from the retainer. A locking arrangement compresses the biasing member when locked and releases the biasing member when actuated by depression of the plunger, which moves the prong against the retainer. The biasing member moves the needle and stylet from the injection position to the retracted position when released.

A plunger, a needle assembly and a retractable syringe comprising same are provided. The plunger comprises a plunger member and a plunger outer having a lock spring that prevents or impedes movement of the plunger member after needle retraction. The plunger further comprises another locking member for engaging the barrel to prevent or impede further movement of the plunger outer after delivery of fluid contents. The plunger member has a plunger seal which engages a retractable needle of the needle assembly for retraction. The retractable needle comprises a cannula and needle body with a plurality of fluid channels that co-operate with a fluid conduit of the plunger seal to efficiently direct fluid to the cannula. A needle retainer comprises a plurality of barbed arms releasably coupled to the needle body, whereby an ejector with tabs facilitates release of the retractable needle from the needle retainer to allow compressed spring-driven retraction.

The invention relates to a Safe Syringe comprising a barrel, a needle seat and a plunger, wherein the needle seat has a hook rod, a linkage deformation portion and a barrel clamping portion; and the plunger has a rod body, and a hook insertion hole which can be sleeved with the hook rod of the needle seat and compress the linkage deformation portion for elastic deformation such that the barrel clamping portion of the needle seat is not clamped into the seat clamping slot of the barrel, and the hook insertion hole can hook the hook rod of the needle seat to move the needle seat. The Safe Syringe can allow stable positioning and quick pullback of the needle seat and effectively reduce liquid medicine residue.

The present embodiments provide for a syringe and a retraction plunger assembly configured to accept various retractable needle assemblies, which are capable of cooperating to provide a retraction safety syringe. In particular, the syringe includes a barrel and a retraction plunger assembly comprising a control unit attached to a plunger and releasably engaged to a housing, and at least one biasing means disposed within the plunger assembly. Upon completion of dose delivery via a retractable needle, the control unit disengages from housing and the biasing member retracts the plunger and a connected needle into the barrel. Various elements are configured to prevent further use of the syringe. The control unit can be used to control a rate of needle retraction.

A safety syringe structure includes a combined structure of a syringe barrel, a needle retreater, a needle, and a plunger. The needle retreater and the plunger are slidably received in the syringe barrel. The needle retreater is arranged adjacent to the front end of the syringe barrel. The needle is coupled to the needle retreater. The plunger has an end extended to form a sharp tip and is provided with a plug facing the needle retreater. The sharp tip extends outside the plug in a direction toward the needle retreater. The sharp tip is movable with the plunger toward the front end of the syringe barrel to pierce into and couple with the through hole of the needle retreater; and the sharp tip is movable with the plunger toward the rear end of the syringe barrel to drive, through the needle retreater, the needle into the channel.

One embodiment is directed to a safety syringe system, comprising: an off-the-shelf syringe assembly comprising a syringe body and a plunger tip; a needle assembly removably coupleable to the distal end of the syringe body such that medicinal fluid may be transferred through a retractable needle coupled to a needle housing comprising the needle assembly upon insertion of the plunger tip relative to the syringe body; and a plunger control assembly coupled to the plunger tip and configured to facilitate manual insertion of the plunger tip relative to the syringe body; wherein upon insertion of the plunger tip to a final insertion state and release of an associated manual insertion load, the plunger tip may be proximally withdrawn, pulling the retractable needle proximally relative to the needle housing to a safe locked and retracted state wherein it is no longer exposed for injection.

A plunger, a needle assembly and a retractable syringe comprising same are provided. The plunger comprises a plunger member and a plunger outer having a lock spring that prevents or impedes movement of the plunger member after needle retraction. The plunger further comprises another locking member for engaging the barrel to prevent or impede further movement of the plunger outer after delivery of fluid contents. The plunger member has a plunger seal which engages a retractable needle of the needle assembly for retraction. The retractable needle comprises a cannula and needle body with a plurality of fluid channels that co-operate with a fluid conduit of the plunger seal to efficiently direct fluid to the cannula. A needle retainer comprises a plurality of barbed arms releasably coupled to the needle body, whereby an ejector with tabs facilitates release of the retractable needle from the needle retainer to allow compressed spring-driven retraction.

A syringe and needle assembly includes an elongated hollow barrel, a needle unit, and a plunger assembly. The hollow barrel has a connecting portion. The needle unit is disposed at the connecting portion and has an engaging structure, and the engaging structure is located in the hollow barrel. A plunger rod of the plunger assembly is movably disposed in the hollow barrel and has a pushing portion and an operating portion formed in front and rear ends of the plunger rod respectively, and the pushing portion faces the connecting portion and has a plurality of elastic hooks. The plunger assembly is adapted to move towards the connecting portion to push a liquid in the hollow barrel to be injected through a needle of the needle unit, and the plunger assembly is adapted to keep moving towards the connecting portion, such that the elastic hooks are engaged with the engaging structure.