Prefillable hypodermic syringe and method of assembling the syringe

Claim 2

A prefillable hypodermic syringe assembly, comprising: (a) an open ended barrel having opposite front and back ends; (b) a resilient sealing bung disengagably connected with and closing the front end of said barrel, said bung including an opening therethrough for the passage of liquid medication from within said barrel; (c) cap means for closing said opening until said assembly is used, at which time said cap means can be removed, said cap means including means for engaging the front end of said bung so as to cause the latter to collapse upon itself sufficient to close said opening whereby to prevent any liquid medication within said chamber from coming in contact with said cap means; (d) a hollow syringe needle; (e) means for supporting said needle in fluid communication with the front end of said bung opening during use of the assembly; (f) a resilient plunger disposed within said barrel and spaced rearwardly of said bung at a predetermined storage position, whereby to define a medication chamber therebetween; and (g) means disposed partially within and partially outside said barrel and engagable with said plunger for moving the latter from its storage position to a position adjacent said bung, whereby to cause liquid medication within said chamber to be forced through said bung opening and said needle when the latter is supported in fluid communication with said opening.

Claim 3

An assembly according to claim 1 wherein said barrel is constructed of glass and wherein said plunger and bung are constructed of rubber, whereby until said assembly is used any medication within said chamber comes in contact with glass and rubber only.

Claim 4

An assembly according to claim 1 wherein said bung includes a forwardmost section located outside and in sealing engagement against the front end of said barrel and a smaller rearwardmost portion extending into and against the inner surface of said barrel from its front end, said rearwardmost portion including at least one groove extending its entire length and opening out to the inner surface of said barrel.

Claim 5

An assembly according to claim 1 wherein said needle support means includes an intermediate luer cap disengagably connected over said bung and wherein said cap means includes an outer cap section disengagably connected over said intermediate cap, said outer cap sector including a rearward projection serving as said bung engaging means extending through said intermediate cap and engaging the front end of said bung across said opening, said bung being designed to collapse internally sufficient to close said opening as a result of the engagement of said projection.

Claim 6

An assembly according to claim 4 wherein said means engaging said plunger is cylindrical and hollow and includes disengagable means for closing its back end whereby to define a chamber therein, said last-mentioned chamber serving to contain said needle until the latter is ready for use.

Claim 7

A prefilled hypodermic syringe assembly, comprising: (a) an elongated, open ended glass barrel having opposite front and back ends; (b) a resilient rubber sealing bung having a central through opening, said bung being disengagably connected with and sealing closed the front end of said barrel, except for said opening, the latter serving to pass liquid medication therethrough from said barrel when said assembly is in use; (c) an inner cap disengagably disposed over said sealing bung for supporting a hollow syringe needle in fluid communication with the front end of said bung opening during use of said syringe assembly, said inner cap including its own through hole coextensive with but larger than said bung opening; (d) an inner plastic cap disengagably connected with said inner cap and including a rearwardly extending plastic projection extending through the through hole in said inner cap and in engagement with the front end of said sealing bung so as to cause the latter to collapse internally upon itself sufficient to close said opening; (e) a resilient rubber plunger disposed within said barrel and spaced rearwardly of said bung at a predetermined storage position, whereby to define a medication chamber therebetween; (f) a cylindrical plunger support disposed partially within and partially outside of said glass barrel and having an opened back end and a front end connected with said plunger for moving the latter from its storage position to a position adjacent said bung, whereby to cause any liquid medication within said chamber to be forced out through said bung opening and through a hollow syringe needle when the latter is supported by said inner cap in fluid communication with said opening; (g) a hollow syringe needle disposed within said cylindrical plunger support; (h) means for closing the back end of said cylindrical plunger support with said needle contained therein; and (i) means for disengagably maintaining said plunger support in a fixed position relative to said barrel such that in its said plunger remains in its predetermined storage position.

Claim 8

A prefilled hypodermic syringe assembly, comprising: (a) an elongated, open ended glass barrel having opposite front and back ends; (b) a resilient rubber sealing bung having a central through opening, said bung being disengagably connected with and sealing closed the front end of said barrel, except for said opening, the latter serving to pass liquid medication therethrough from said barrel when said assembly is in use; (c) an inner cap disengagably disposed over said sealing bung for supporting a hollow syringe needle in fluid communication with the front end of said bung opening during use of said syringe assembly, said inner cap including its own through hole coextensive with but larger than said bung opening; (d) an inner plastic cap disengagably connected with said inner cap and including a rearwardly extending plastic projection extending through the through hole in said inner cap and in engagement with the front end of said sealing bung so as to cause the latter to collapse internally upon itself sufficient to close said opening; (e) a resilient rubber plunger disposed within said barrel and spaced rearwardly of said bung at a predetermined storage position, whereby to define a medication chamber therebetween; (f) a cylindrical plunger support disposed partially within and partially outside of said glass barrel and having an opened back end and a front end connected with said plunger for moving the latter from its storage position to a position adjacent said bung, whereby to cause any liquid medication within said chamber to be forced out through said bung opening and through a hollow syringe needle when the latter is supported by said inner cap in fluid communication with said opening; (g) a hollow syringe needle disposed within said cylindrical plunger support; (h) means for closing the back end of said cylindrical plunger support with said needle contained therein; and (i) means for disengagably maintaining said plunger support in a fixed position relative to said barrel such that in its said plunger remains in its predetermined storage position.

Claim 9

An assembly according to claim 6 wherein said sealing bung includes a forwardmost section located outside and in sealing engagement against the front end of said glass barrel and a smaller rearwardmost portion extending into and against the inner surface of said barrel from its front end, said rearwardmost portion including at least one groove extending its entire length and opening out to the inner surface of said barrel.