Abstract: 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.

Abstract: A replaceable needle assembly is provided for a retractable, prefilled syringe comprising a barrel having a mounting member and a plunger, whereby the retractable needle can be replaced by a user without affecting the retraction mechanism. The replaceable needle assembly comprises a needle fitted to a retractable needle mount and a needle retainer. The needle mount is removably, screw-threadedly mountable to the mounting member of the barrel. The needle retainer comprises a plurality of fingers that releasably engage the retractable needle to thereby prevent inadvertent retraction of the retractable needle before engagement by the plunger. The plunger comprises a plunger seal comprising an outer member and an inner member that engages the needle for spring-driven retraction. At the end of retraction, a lock is formed between the plunger and barrel to prevent re-use of the syringe.

Abstract: A replaceable needle assembly is provided for a retractable, prefilled syringe comprising a barrel having a mounting member and a plunger, whereby the retractable needle can be replaced by a user without affecting the retraction mechanism. The replaceable needle assembly comprises a needle fitted to a retractable needle mount and a needle retainer. The needle mount is removably, screw-threadedly mountable to the mounting member of the barrel. The needle retainer comprises a plurality of fingers that releasably engage the retractable needle to thereby prevent inadvertent retraction of the retractable needle before engagement by the plunger. The plunger comprises a plunger seal comprising an outer member and an inner member that engages the needle for spring-driven retraction. At the end of retraction, a lock is formed between the plunger and barrel to prevent re-use of the syringe.

Abstract: 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.

Abstract: A replaceable needle assembly is provided for a retractable, prefilled syringe comprising a barrel having a mounting member and a plunger, whereby the retractable needle can be replaced by a user without affecting the retraction mechanism. The replaceable needle assembly comprises a needle fitted to a retractable needle mount and a needle retainer. The needle mount is removably, screw-threadedly mountable to the mounting member of the barrel. The needle retainer comprises a plurality of fingers that releasably engage the retractable needle to thereby prevent inadvertent retraction of the retractable needle before engagement by the plunger. The plunger comprises a plunger seal comprising an outer member and an inner member that engages the needle for spring-driven retraction. At the end of retraction, a lock is formed between the plunger and barrel to prevent re-use of the syringe.

Abstract: An actuation mechanism for an automatic injector includes a first actuation spring, a first actuation pill, a second actuation spring, and a second actuation pill. In an initial configuration the first actuation spring resides in a compressed, energized state substantially within an upper portion of first actuation pill and the second actuation spring resides in a compressed, energized state between the first actuation pill and the second actuation pill. An automatic injector includes a housing, an activation mechanism, an actuation mechanism, and a syringe cartridge having a plunger and a needle assembly. A retractable syringe may be utilized as a syringe cartridge, such as a prefilled retractable syringe with integrated safety features which retract the needle after use. The automatic injector may be utilized to inject the needle, deliver a drug treatment, and activate retraction of the needle. Methods of assembly and operation are also provided.

Abstract: 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.

Abstract: A retractable syringe, plunger and releasable needle assembly including a retractable needle, a needle seal, a retaining member and an ejector member. The retaining member has a mating surface for mounting to a complementary mating surface of an interior wall of a syringe barrel. The plunger comprises a plunger outer, a plunger rod frangibly connected to a controlling member, a spring and a unitary plunger seal capable of engaging the retractable needle, wherein the plunger rod, plunger outer and the controlling member co-operate to releasably maintain the spring in an initially compressed state. After delivery of fluid contents of the syringe, the plunger forces the ejector member to release the retractable needle from the retaining member. Decompression of the spring at the end of depression of the plunger facilitates retraction of the retractable needle when engaged with the unitary plunger seal.

Abstract: A retractable needle is provided for a syringe comprising a barrel and a plunger that comprises a portion capable of engaging the retractable needle for retraction. The retractable needle comprises a cannula, a needle body having a plunger-engaging member, at least one aperture and an elongate portion which houses the cannula, the cannula comprising an end which is in fluid communication with the at least one aperture, wherein the at least one aperture is located between the plunger-engaging member and the elongate portion. The positioning of the at least one aperture distal to the plunger-engaging member maximizes the efficiency of fluid delivery.

Abstract: A replaceable needle assembly is provided for a retractable, prefilled syringe comprising a barrel having a mounting member and a plunger, whereby the retractable needle can be replaced by a user without affecting the retraction mechanism. The replaceable needle assembly comprises a needle fitted to a retractable needle mount and a needle retainer. The needle mount is removably, screw-threadedly mountable to the mounting member of the barrel. The needle retainer comprises a plurality of fingers that releasably engage the retractable needle to thereby prevent inadvertent retraction of the retractable needle before engagement by the plunger. The plunger comprises a plunger seal comprising an outer member and an inner member that engages the needle for spring-driven retraction. At the end of retraction, a lock is formed between the plunger and barrel to prevent re-use of the syringe.

Abstract: An adapter mountable to a retractable syringe barrel comprises a body that includes a needle portion and a barrel-engaging portion and a needle aperture. The adapter facilitates mounting a needle assembly to the barrel. The needle assembly comprises a needle body and cannula and an immobile, compressible needle seal, wherein the needle body and the needle seal are releasably engaged. The needle seal is engageable with a needle portion of the adapter. The needle body comprises one or more fluid reclaim channels that facilitate efficient delivery of the fluid contents of the retractable syringe. The retractable syringe also comprises dual locking systems to impede or prevent re-use.

Abstract: A replaceable needle assembly is provided for a retractable, prefilled syringe comprising a barrel having a mounting member and a plunger, whereby the retractable needle can be replaced by a user without affecting the retraction mechanism. The replaceable needle assembly comprises a needle fitted to a retractable needle mount and a needle retainer. The needle mount is removably, screw-threadedly mountable to the mounting member of the barrel. The needle retainer comprises a plurality of fingers that releasably engage the retractable needle to thereby prevent inadvertent retraction of the retractable needle before engagement by the plunger. The plunger comprises a plunger seal comprising an outer member and an inner member that engages the needle for spring-driven retraction. At the end of retraction, a lock is formed between the plunger and barrel to prevent re-use of the syringe.

Abstract: A replaceable needle assembly is provided for a retractable syringe comprising a barrel and a plunger, whereby the retractable needle can be replaced by a user without affecting the retraction mechanism. A mounting member is removably mountable to the barrel by way of a screw-thread connection and a needle mount is removably coupled to the mounting member. A needle is mounted to the needle mount. The barrel comprises a needle mount retainer that comprises a plurality of fingers that engage the retractable needle mount to prevent inadvertent retraction. The plunger comprises a collapsible seal which maximizes the efficiency of fluid delivery prior to the plunger engaging the retractable needle mount for retraction. An initially compressed spring decompresses to drive retraction of the plunger and the engaged needle mount. A lock formed between the plunger and barrel prevents further use of the plunger after retraction.

Abstract: 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.

Abstract: 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.

Abstract: A retractable needle is provided for a syringe comprising a barrel and a plunger that comprises a portion capable of engaging the retractable needle for retraction. The retractable needle comprises a cannula, a needle body having a plunger-engaging member, at least one aperture and an which is in fluid communication with the at least one aperture, wherein the at least one aperture is located between the plunger-engaging member and the elongate portion. The positioning of the at least one aperture distal to the plunger-engaging member maximizes the efficiency of fluid delivery.

Abstract: An actuation mechanism for an automatic injector includes a first actuation spring, a first actuation pill, a second actuation spring, and a second actuation pill. In an initial configuration the first actuation spring resides in a compressed, energized state substantially within an upper portion of first actuation pill and the second actuation spring resides in a compressed, energized state between the first actuation pill and the second actuation pill. An automatic injector includes a housing, an activation mechanism, an actuation mechanism, and a syringe cartridge having a plunger and a needle assembly. A retractable syringe may be utilized as a syringe cartridge, such as a prefilled retractable syringe with integrated safety features which retract the needle after use. The automatic injector may be utilized to inject the needle, deliver a drug treatment, and activate retraction of the needle. Methods of assembly and operation are also provided.

Abstract: An actuation mechanism for an automatic injector includes a first actuation spring, a first actuation pill, a second actuation spring, and a second actuation pill. In an initial configuration the first actuation spring resides in a compressed, energized state substantially within an upper portion of first actuation pill and the second actuation spring resides in a compressed, energized state between the first actuation pill and the second actuation pill. An automatic injector includes a housing, an activation mechanism, an actuation mechanism, and a syringe cartridge having a plunger and a needle assembly. A retractable syringe may be utilized as a syringe cartridge, such as a prefilled retractable syringe with integrated safety features which retract the needle after use. The automatic injector may be utilized to inject the needle, deliver a drug treatment, and activate retraction of the needle. Methods of assembly and operation are also provided.

Abstract: A syringe is provided which comprises a barrel (11) and a needle sheath (30) slidably located within the barrel, a plunger (20) with a plunger seal (23), a needle, a needle sheath (30) and a sheath seal (50), arranged so that depression of the plunger forces the needle sheath to move into a position where it covers or at least partly encloses the needle after delivery of fluid contents of the syringe. The needle sheath may be manually actuated or may be actuated by decompression of a spring. The syringe may further comprise a plunger disabling means operable to impede, prevent or otherwise hinder withdrawal of the plunger during or following depression of the plunger. The syringe may be a pre-filled syringe or a syringe which is filled by a user.

Abstract: An adapter mountable to a retractable syringe barrel comprises a body that includes a needle portion and a barrel-engaging portion and a needle aperture. The adapter facilitates mounting a needle assembly to the barrel. The needle assembly comprises a needle body and cannula and an immobile, compressible needle seal, wherein the needle body and the needle seal are releasably engaged. The needle seal is engageable with a needle portion of the adapter. The needle body comprises one or more fluid reclaim channels that facilitate efficient delivery of the fluid contents of the retractable syringe. The retractable syringe also comprises dual locking systems to impede or prevent re-use.