Automatic medicament injector employing non-coring needle

• US 5,709,668 A
• Filed: 06/06/1995
• Issued: 01/20/1998
• Est. Priority Date: 01/16/1991
• Status: Expired due to Term

• Current Assignee: Ranbaxy Pharmaceuticals Incorporated (Daiichi Sankyo Company Limited)
• Original Assignee: Senetek Plc
• Inventors: Wacks, Jonathan L.
• Primary Examiner(s): Buiz, Michael Powell
• Assistant Examiner(s): STRIGHT, RONALD K
• Application Number:
  US08/465,790
• Time in Patent Office: 959 Days
• Field of Search: 128/DIG. 4, 604/232, 604/234, 604/194, 604/195, 604/196, 604/200, 604/201, 604/202, 604/213, 604/110, 604/156, 604/137, 604/138-139, 604/403, 604/205-206, 604/197 , 604/121-123, 604/130, 604/411, 604/412, 604/413-416, 604/233-237, 604/239-240, 604/144, 604/146, 604/171, 604/272, 604/274, 604/905, 604/131 , 604/134, 604/135, 604/136, 222/326, 222/386, 141/27, 141/329, 141/330, 141/383, 141/385, 141/386
• US Class Current: 604/232
• CPC Class Codes: A61M 2005/206 With automatic needle insertion
• CPC Class Codes: A61M 2005/2073 preventing premature release, e.g. by making use of a safety lock
• CPC Class Codes: A61M 2005/247 with fixed or steady piercing means, e.g. piercing under movement of ampoule
• CPC Class Codes: A61M 2005/3118 via the distal end of a syringe, i.e. syringe end for mounting a needle cannula
• CPC Class Codes: A61M 2005/3131 specially adapted for improving sealing or sliding
• CPC Class Codes: A61M 2005/3231 Proximal end of needle captured or embedded inside piston head, e.g. by friction or hooks
• CPC Class Codes: A61M 2205/195 by the needle tip shape
• CPC Class Codes: A61M 2205/60 with identification means
• CPC Class Codes: A61M 25/0693 Flashback chambers
• CPC Class Codes: A61M 5/2033 Spring-loaded one-shot injectors with or without automatic needle insertion multishot dosing syringes A61M5/31525, needle insertion only A61M5/3287
• CPC Class Codes: A61M 5/24 Ampoule syringes, i.e. syringes with needle for use in combination with replaceable ampoules or carpules, e.g. automatic ampoules or carpules A61J1/06
• CPC Class Codes: A61M 5/2448 comprising means for injection of two or more media, e.g. by mixing
• CPC Class Codes: A61M 5/288 by piercing without internal pressure increase A61M5/283 takes precedence
• CPC Class Codes: A61M 5/32 Needles; Details of needles pertaining to their connection with syringe or hub infusion needles A61M5/158; Accessories for bringing the needle into, or holding the needle on, the body A61M5/42, A61M5/46 take precedence; guide needles for catheters A61M25/065; Devices for protection of needles apparatus specially adapted for cleaning or sterilising needles A61M5/001
• CPC Class Codes: A61M 5/3202 Devices for protection of the needle before use, e.g. caps A61M5/50 takes precedence; for infusion spikes A61M5/1626; protectors for sharps A61B50/3001
• CPC Class Codes: 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
• CPC Class Codes: A61M 5/3286 Needle tip design, e.g. for improved penetration
• CPC Class Codes: A61M 5/3291 Shafts with additional lateral openings
• CPC Class Codes: A61M 5/348 snap lock, i.e. upon axial displacement of needle assembly A61M5/344 takes precedence
• CPC Class Codes: A61M 5/46 having means for controlling depth of insertion

Abstract

An automatic medicament injector employing a non-coring needle having side port geometry optimized to minimize or eliminate the coring of a rubber seal or septum when impaled by the internal needle tip of the cannula. The geometry avoids direct exposure of the butt end face of the needle to the rubber seal by providing a crimp to the material at the butt end and openings in the side thereof using electro-discharge machining (EDM) processes providing plural openings therein for introduction of medicament or aspiration through the side port geometry. The automatic medicament injector structure facilitates administration of a medicament to a predetermined target tissue avoiding exposure of the medicament or drug to tissues which would undesirably be damaged by such exposure. A needle housing assembly is disposed in a cylindrical bore of the injector cartridge wherein actuation causes the needle housing assembly to move to a widened second end of the cartridge having a needle housing assembly residence chamber for receiving the needle housing assembly when the needle housing assembly and the ampule are a predetermined distance apart.

Claims

1. A fluid injector comprising:

(A) a tubular cartridge having an upper end and a lower end, said cartridge having an interior bore which widens at said lower end of said cartridge to form a needle housing assembly residence chamber for receiving a needle housing assembly;

(B) a puncturable end cap sealing said lower end of said cartridge;

(C) an ampule slidably disposed within the upper end of said cartridge bore, said ampule having an upper end and a lower end and being suitable for storing a fluid charge to be expelled therefrom;

(D) a piston slidably seated within said upper end of said ampule;

(E) a puncturable ampule end stopper rigidly attached to and sealing said lower end of said ampule;

(F) a needle housing assembly slidably disposed within said upper end of said cartridge below said ampule, said needle housing assembly comprising;

a generally cup-shaped housing having a housing bottom and flexible upstanding housing wall sections attached to the periphery of said housing bottom, said housing walls, extending toward said lower end of said ampule and said housing wall sections having upper edges for engaging with said lower end of said ampule,

a hollow injection needle extending through and rigidly engaged by said housing bottom and having an internal section, and an external section, said internal section of said hollow injection needle extending from said housing bottom, upwardly within said housing walls, toward said puncturable ampule end stopper, and said external section of said hollow injection needle extending from said housing bottom downwardly toward said puncturable end cap of said cartridge without protruding from said puncturable end cap,

the upper edges of said housing wall sections being engageable with said lower end of said ampule as said ampule slides downwardly within said cartridge bore, whereby actuation moves said ampule downwardly within said cartridge bore in said upper end of said cartridge toward said lower end of said cartridge thus engaging said upper edges of said housing wall sections and moving said needle housing assembly from said upper end of said cartridge into said needle housing assembly residence chamber at said lower end of said cartridge causing said external section of said hollow injection needle to protrude through said puncturable end cap and allowing said flexible housing wall sections to expand outwardly in said needle housing assembly residence chamber, the further downward movement of said ampule causing the internal section of said hollow injection needle to pass through said puncturable ampule end stopper thereby allowing fluid to be injected outwardly through said hollow injection needle; and

(G) an actuator for engaging said tubular cartridge and for propelling said ampule toward said puncturable end cap and for propelling said piston within said ampule toward said ampule end stopper to inject a fluid.

2. A fluid injector according to claim 1, wherein said actuator (G) comprises:

(i) an actuator housing having a first end and a second end, said first end for receiving said piston and said second end for operating said actuator;

(ii) an elongated piston driver slidably seated in said actuator housing, said piston driver having a piston face for contacting said piston, a transfer surface for transferring propelling force from said actuator housing to said piston driver, and a trigger end for releasably engaging said second end of said actuator housing;

(iii) a seat flange in said second end of said actuator housing for releasably engaging said piston driver;

(iv) a release flange in said second end of said actuator housing on said piston driver for disengaging said piston driver from said second end;

(v) a propulsion mechanism connected between said transfer surface and said second end of said housing for driving said piston driver toward said puncturable end cap when said piston driver is disengaged by said release flange.

3. A fluid injector as in claim 2, wherein the hollow injection needle is a non-corning hollow injection needle.

4. A fluid injector as in claim 3, wherein the non-corning hollow injection needle has an internal end section and an external end section, said internal end section of said non-corning hollow injection needle extending from said needle housing assembly toward said puncturable ampule end stopper, said non-corning hollow injection needle having a pressed closure at the tip of said internal end section and a sideport opening therebelow, thereby allowing medicament to be injected outwardly through said non-coring hollow injection needle via said sideport opening.

5. A fluid injector as in claim 2, wherein said propulsion mechanism is a spring connected between said transfer surface and said second end of said housing.

6. A fluid injector as in claim 1, further comprising locking means located at said actuator for preventing unintentional discharge of said fluid injector.

7. A fluid injector as in claim 6, wherein said locking means comprises a removable safety pin having a projection projecting into said actuator for preventing activation of said actuator.

8. A fluid injector as in claim 1, wherein the hollow injection needle is a non-corning hollow injection needle.

9. A fluid injector as in claim 8, wherein the non-corning hollow injection needle has an internal end section and an external end section, said internal end section of said non-corning hollow injection needle extending from said needle housing assembly toward said puncturable ampule end stopper, said non-corning hollow injection needle having a pressed closure at the tip of said internal end section and a sideport opening therebelow, thereby allowing medicament to be injected outwardly through said non-coring hollow injection needle via said sideport opening.

10. A fluid injector according to claim 1, wherein said needle housing assembly is provided with locking means for irreversibly locking said needle assembly housing to said ampule when said needle housing assembly and said ampule are a predetermined distance apart.

11. A fluid injector as in claim 1, wherein said external end of said injection needle is disposed within said puncturable end cap of said cartridge a sufficient distance to provide a microbe-impermeable seal without protruding therefrom.

14. An automatic injector in accordance with claim 2 wherein said pressed closure comprises a crimp at the tip of said internal end section of said hollow injection needle providing a closure having rugged lacerations therein.

12. An automatic medicament injector employing a non-coring needle, comprising:

a tubular cartridge having an upper end and a lower end with a cartridge bore defined by a cartridge bore wall extending between the upper end and the lower end, said lower end of said cartridge bore widening to form a needle housing assembly residence chamber for receiving a needle housing assembly;

an ampule slidably disposed within the upper end of said cartridge bore, said ampule having an upper end and a lower end and being suitable for storing a medicament charge to be expelled therefrom;

a puncturable ampule end stopper rigidly attached to and sealing said lower end of said ampule;

a piston contacting said ampule for driving said ampule in order to expel said medicament charge therefrom; and

a needle housing assembly slidably disposed within said upper end of said cartridge below said ampule, said needle housing assembly comprising;

a generally cup-shaped housing having a housing bottom and flexible upstanding housing wall sections attached to the periphery of said housing bottom, said housing walls extending toward said lower end of said ampule and said housing wall having upper edges for engaging with a lower end of said ampule,

a non-coring hollow injection needle extending through and rigidly engaged within the needle housing assembly and having an internal end section and an external end section, said internal end section of said hollow injection needle extending from said housing assembly toward said puncturable ampule end stopper, said hollow injection needle having a pressed closure at the tip of said internal end section and a sideport opening therebelow, and

the upper edges of said housing wall sections being engageable with said lower end of said ampule as said ampule slides downwardly within said cartridge bore, whereby actuation moving said ampule within said cartridge bore in said upper end of said cartridge toward said lower end of said cartridge thus engages said housing and moves said needle housing assembly from said upper end of said cartridge into said needle housing assembly residence chamber at said lower end of said cartridge, the further downward movement of said ampule driven by said piston causing the pressed closure at the tip of said internal end section to pass through said puncturable ampule end stopper thereby allowing medicament to be injected outwardly through said non-coring needle via said sideport opening.

13. An automatic injector in accordance with claim 12 wherein said sideport opening below the tip of said internal end section comprises a plurality of slots in said internal end section of said hollow injection needle.

15. An automatic injector in accordance with claim 12 comprising an actuator for engaging said tubular cartridge and for propelling said ampule toward said non-corning hollow injection needle and for propelling said piston within said ampule toward said ampule end stopper to inject the medicament.

16. An automatic injector in accordance with claim 15, wherein said actuator comprises:

(i) an actuator housing having a first end and a second end, said first end for receiving said piston and said second end for operating said actuator;

(ii) an elongated piston driver slidably seated in said actuator housing, said piston driver having a piston face for contacting said piston, a transfer surface for transferring propelling force from said actuator housing to said piston driver, and a trigger end for releasably engaging said second end of said actuator housing;

(iii) a seat flange in said second end of said actuator housing for releasably engaging said piston driver;

(iv) a release flange in said second end of said actuator housing on said piston driver for disengaging said piston driver from said second end;

(v) a propulsion mechanism connected between said transfer surface and said second end of said housing for driving said piston driver toward said puncturable end cap when said piston driver is disengaged by said release flange.