Automatic injector

An automatic injector comprising:

• a housing having opposed forward and rearward end portions, said forward end portion being engageable with a portion of flesh defining an injection site;
• a needle assembly comprising a needle carrier with a sterilized interior, a tubular substantially rigid protective needle cover with a sterilized interior, and a sterilized needle mounted within said needle carrier, said needle having a forward tip portion, a rearward tip portion, and a fluid passageway formed therein open to said forward and rearward tip portions;
• said needle cover having a substantially rigid tubular wall defining a forwardly facing needle passing opening and a rearwardly facing needle carrier receiving opening, said needle carrier and said needle being mounted within said needle carrier receiving opening;
• said needle carrier being movable relative to said housing and said protective needle cover between (1) a normal, inoperative position wherein said needle is disposed entirely within said housing and said needle cover and (2) an injecting position wherein the forward tip portion of said needle extends forwardly of said housing forward end portion through the needle passing opening in said protective needle cover;
• said needle assembly further comprising a first sealing member substantially sealing said needle passing opening when said needle carrier is in said inoperative position thereof and a second sealing member having an annular shape and being disposed between said needle carrier and said needle cover so as to substantially seal the needle guide receiving opening of said needle cover when said needle carrier is in said inoperative position thereof;
• a medicament cartridge having a sealed interior containing a supply of fluid medicament, said needle carrier having a tubular cartridge mounting portion defining a rearwardly facing opening and said cartridge being mounted to said cartridge mounting portion of said needle carrier;
• said medicament cartridge being normally sealed from said needle, said medicament cartridge and said needle being constructed and arranged to be fluidly communicated during an automatic injecting operation such that the rearward tip portion of said needle pierces said cartridge and extends rearwardly into said cartridge interior so as to fluidly communicate the fluid passageway of said needle with said cartridge interior and allow the fluid medicament contained in said cartridge interior to flow into said fluid passageway;
• a third sealing member having an annular shape and being disposed between said tubular cartridge mounting portion of said needle carrier and said cartridge so as to substantially seal the rearwardly facing opening of said cartridge mounting portion when said cartridge is in said inoperative position thereof;
• said first sealing member, said second sealing member and said third sealing member cooperating with the sterilized interior of said needle cover and the sterilized interior of said needle carrier to define a substantially sealed sterilized needle chamber with said sterilized needle disposed therein such that unsterilized ambient air is prevented from entering said needle chamber and contaminating either said needle or said chamber;
• a manually operable drive assembly having an actuator extending generally rearwardly from the rearward end portion of said housing, said drive assembly being constructed and arranged such that a user can perform the automatic injecting operation by engaging the forward end portion of said housing with the aforesaid injection site and manually operating said actuator such that said drive assembly moves said needle to said injecting position thereof and causes said cartridge and said needle to be fluidly communicated so that the forward tip portion of said needle pierces the injection site and the rearward tip portion of said needle pierces said cartridge, said drive assembly subsequently forcing the fluid medicament outwardly from said cartridge interior through the fluid passageway of said needle and into the injection site.

An automatic injector comprising:

• a housing having opposed forward and rearward end portions, said forward end portion being engageable with a portion of flesh defining an injection site;
• a needle assembly comprising a needle carrier with a sterilized interior, and a sterilized needle mounted within said needle carrier, said needle having a forward tip portion, a rearward tip portion, and a fluid passageway open to both said forward and rearward tip portions;
• said needle carrier being movable relative to said housing between (1) a normal, inoperative position wherein said needle is disposed entirely within said housing and (2) an injecting position wherein the forward tip portion of said needle extends forwardly of said forward end portion;
• said needle assembly comprising sealing structure substantially sealing a forward portion of said needle carrier and the forward tip portion of said needle;
• a medicament cartridge having a sealed interior containing a supply of fluid medicament;
• said needle carrier having a tubular cartridge mounting portion defining a rearwardly facing opening, said cartridge being slidably mounted to said cartridge mounting portion of said needle carrier;
• said medicament cartridge being movable relative to said needle between (1) a normal, inoperative position wherein said cartridge is unpierced and disposed rearwardly of the rearward tip portion of said needle and (2) a medicament supplying position wherein said cartridge is moved forwardly of said inoperative position thereof such that the rearward tip portion of said needle pierces said cartridge and extends rearwardly into said cartridge interior so as to fluidly communicate the fluid passageway of said needle with said cartridge interior and allow the fluid medicament contained in said cartridge interior to flow into said fluid passageway;
• an annular sealing member disposed between said cartridge and said cartridge mounting portion of needle carrier so as to substantially seal the rearwardly facing opening of said cartridge mounting portion when said cartridge is in said inoperative position thereof;
• said sealing structure and said sealing member cooperating with the sterilized interior of said needle carrier to define a substantially sealed sterilized needle chamber with said needle disposed therein such that unsterilized ambient air is prevented from entering said needle chamber and contaminating either said needle or said chamber when both said needle carrier and said cartridge are in the inoperative positions thereof;
• said tubular cartridge mounting portion having at least one generally axially extending groove formed thereon, said groove being positioned and configured to allow air to escape from the sterilized interior of said cartridge mounting portion as said cartridge is being moved forwardly to said medicament supplying position thereof to thereby prevent a pressure build-up in said cartridge mounting portion;
• a manually operable drive assembly having an actuator extending generally rearwardly from the rearward end portion of said housing, said drive assembly being constructed and arranged such that a user can perform an automatic injecting operation by engaging the forward end portion of said housing with the aforesaid injection site and thereafter manually operating said actuator such that said drive assembly moves both said needle carrier to said injecting position thereof and said cartridge to said medicament supplying position thereof so that the forward tip portion of said needle pierces the injection site and the rearward tip portion of said needle pierces said cartridge and then said drive assembly forces the fluid medicament outwardly from said cartridge interior through the fluid passageway of said needle and into the injection site.

An automatic injector comprising:

• a housing having opposed forward and rearward end portions, said forward end portion being engageable with a portion of flesh defining an injection site;
• a needle having a forward tip portion, a rearward tip portion, and a fluid passageway formed therein open to said forward and rearward tip portions;
• said needle being movable relative to said housing between (1) a normal, inoperative position wherein said needle is disposed entirely within said housing and (2) an injecting position wherein the forward tip portion of said needle extends forwardly of said housing forward end portion;
• a medicament cartridge having a sealed interior containing a supply of fluid medicament;
• said medicament cartridge being normally sealed from said needle, said medicament cartridge and said needle being constructed and arranged to be fluidly communicated during an automatic injecting operation such that the rearward tip portion of said needle pierces said cartridge and extends rearwardly into said cartridge interior so as to fluidly communicate the fluid passageway of said needle with said cartridge interior and allow the fluid medicament contained in said cartridge interior to flow into said fluid passageway;
• a manually operable drive assembly having an actuator extending generally rearwardly from the rearward end portion of said housing, said drive assembly being constructed and arranged such that a user can perform the automatic injecting operation by engaging the forward end portion of said housing with the aforesaid injection site and manually operating said actuator such that said drive assembly both moves said needle to said injecting position thereof and causes said cartridge and said needle to be fluidly communicated so that the forward tip portion of said needle pierces the injection site and the rearward tip portion of said needle pierces said cartridge, said drive assembly subsequently forcing the fluid medicament outwardly from said cartridge interior through the fluid passageway of said needle and into the injection site;
• said actuator having (1) a head with an exterior side surface, and (2) a forward portion spaced forwardly from said head, and (3) an intermediate portion extending between said forward portion and said head;
• said housing rearward end portion having (1) a first interior surface defining a forward portion receiving space and (2) a second interior surface defining an actuator head receiving space, said forward portion being received in said forward portion receiving space such that said first interior surface supports said forward portion against radial bending with said intermediate portion extending rearwardly away from said forward portion receiving opening and being radially unsupported,
• said exterior side surface and said second interior surface of said housing rearward end portion being positioned and configured such that a portion of said actuator head is received within said actuator head receiving space with said exterior side surface of said actuator head facing said second interior surface of said housing rearward end portion in closely spaced relation so as to limit radial movement of said head to thereby substantially prevent radial bending of said intermediate portion.

An automatic injector comprising:

• a housing having opposed forward and rearward end portions, said forward end portion being engageable with a portion of flesh defining an injection site;
• a needle having a forward tip portion, a rearward tip portion, and a fluid passageway formed therein open to said forward and rearward tip portions;
• said needle being movable relative to said housing between (1) a normal, inoperative position wherein said needle is disposed entirely within said housing and (2) an injecting position wherein the forward tip portion of said needle extends forwardly of said housing forward end portion;
• a medicament cartridge having a sealed interior containing a supply of fluid medicament;
• said medicament cartridge being normally sealed from said needle, said medicament cartridge and said needle being constructed and arranged to be fluidly communicated during an automatic injecting operation such that the rearward tip portion of said needle pierces said cartridge and extends rearwardly into said cartridge interior so as to fluidly communicate the fluid passageway of said needle with said cartridge interior and allow the fluid medicament contained in said cartridge interior to flow into said fluid passageway;
• a manually operable drive assembly having an actuator extending generally rearwardly from the rearward end portion of said housing, said drive assembly being constructed and arranged such that a user can perform the automatic injecting operation by engaging the forward end portion of said housing with the aforesaid injection site and manually operating said actuator such that said drive assembly both moves said needle to said injecting position thereof and causes said cartridge and said needle to be fluidly communicated so that the forward tip portion of said needle pierces the injection site and the rearward tip portion of said needle pierces said cartridge, said drive assembly subsequently forcing the fluid medicament outwardly from said cartridge interior through the fluid passageway of said needle and into the injection site;
• said actuator having, (1) a head with an exterior side surface, (2) a forward portion spaced forwardly from said head, and (3) an intermediate portion extending between said forward portion and said head, said intermediate portion being thinner than said forward portion;
• the rearward end portion of said housing having (1) an interior surface defining an actuator head receiving space and (2) an inwardly extending flange;
• said drive assembly comprising:
• a collet having a pair of flexible arms, and an outwardly extending flange, said collet having a forward end portion engaged with said cartridge;
• a compressed coil spring engaged with said inwardly extending flange of the rearward end portion of the housing and said outwardly extending flange of the collet;
• said inwardly extending flange providing a rearwardly facing locking surface and said flexible arms having end portions providing forwardly facing locking surfaces, said locking surfaces being engaged to prevent said collet from moving forwardly with respect to said housing;
• said forward portion of said actuator being received between said flexible arms so as to prevent inward movement of the end portions of said arms, and said intermediate portion of said actuator extending rearwardly away from said forward portion and said end portions of said arms;
• said actuator being constructed and arranged such that manually moving said actuator forwardly allows the end portions of said flexible arms to collapse inwardly towards the thinner intermediate portion so that said locking surfaces disengage from one another to allow the spring to extend and drive said collet forwardly;
• said exterior side surface of said head and said interior surface of said housing rearward end portion being positioned and configured such that a portion of said actuator head is received within said actuator head receiving space with said exterior side surface of said actuator head facing said interior surface of said housing rearward end portion in closely spaced relation so as to limit radial movement of said head to thereby substantially prevent radial bending of said intermediate portion.

A method for assembling an automatic injector comprising:

• providing a medicament cartridge with a sealed interior containing a supply of fluid medicament;
• providing a sterilized needle and a needle carrier with a sterilized interior, said needle being mounted to said needle carrier and having forward and rearward tip portions and a fluid passageway open to said forward and rearward tip portions, said needle carrier having a tubular cartridge mounting portion defining a rearwardly facing opening;
• providing a substantially rigid tubular needle cover with a sterilized interior, a forwardly facing needle passing opening, and a rearwardly facing needle carrier receiving opening, said needle cover having a first sealing member substantially sealing said needle passing opening;
• providing a second sealing member;
• mounting said needle carrier with said needle mounted thereon to said needle cover in a sterilized area by positioning a forward end portion of said needle carrier within said needle carrier receiving opening with said second sealing member disposed between said needle carrier forward end portion and said needle cover such that said second sealing member substantially seals said needle carrier receiving opening;
• providing a medicament cartridge with a sealed interior containing a supply of fluid medicament;
• providing a third sealing member;
• mounting said cartridge to said cartridge mounting portion of said needle carrier with said third sealing member disposed therebetween in said sterilized area such that said third sealing member substantially seals rearwardly facing opening of said cartridge mounting portion, wherein said first sealing member, said second sealing member, and said third sealing member cooperate with the sterilized interior of said needle carrier and the sterilized interior of said needle cover to define a substantially sealed sterilized needle chamber with said sterilized needle disposed therein such that sterilized ambient air is prevented from entering said needle chamber and contaminating either said needle or said chamber, said needle carrier with said needle mounted thereto, said needle cover, and said cartridge defining a needle and cartridge assembly when mounted together as aforesaid;
• thereafter providing a housing and a manually operable drive assembly;
• and
• then positioning both said drive assembly and said needle and cartridge assembly together within said housing.