Automatic injector with cartridge having separate sequentially injectable medicaments

• US 4,394,863 A
• Filed: 10/23/1981
• Issued: 07/26/1983
• Est. Priority Date: 10/23/1981
• Status: Expired due to Term

• Current Assignee: Survival Technology, Inc. (Meridian Medical Technologies Incorporated)
• Original Assignee: Survival Technology, Inc. (Meridian Medical Technologies Incorporated)
• Inventors: Bartner, Elliot
• Primary Examiner(s): YASKO JR, JOHN D
• Application Number:
  US06/314,381
• Time in Patent Office: 641 Days
• Field of Search: 128/218 R, 128/218 A, 128/218 C, 128/218 F, 128/218 D, 128/218 DA, 128/218 P, 128/213, 128/215, 128/216, 128/234
• US Class Current: 604/90
• CPC Class Codes: A61M 2005/1787 Syringes for sequential delivery of fluids, e.g. first medicament and then flushing liquid
• CPC Class Codes: A61M 2005/2013 triggering of discharging means by contact of injector with patient body
• CPC Class Codes: A61M 2005/206 With automatic needle insertion
• CPC Class Codes: A61M 2005/3132 having flow passages for injection agents at the distal end of the barrel to bypass a sealing stopper after its displacement to this end due to internal pressure increase
• CPC Class Codes: A61M 5/2066 comprising means for injection of two or more media, e.g. by mixing
• CPC Class Codes: A61M 5/286 upon internal pressure increase, e.g. pierced or burst A61M5/283 takes precedence
• CPC Class Codes: A61M 5/31596 comprising means for injection of two or more media, e.g. by mixing

Abstract

An automatic injector comprising an elongated housing assembly having a forward end, a stressed spring assembly mounted within the rearward end of the housing assembly so as to be released in response to a predetermined manual actuation procedure, and a medicament injection cartridge assembly mounted within the forward end of the housing assembly in cooperating relation with the stressed spring assembly. The improvement of the present invention is in the medicament injection cartridge assembly which includes a medicament container, a hypodermic needle disposed forwardly of the container mounted in a sterile condition within the housing assembly adjacent the forward end thereof. A forward seal is provided for sealing the forward end of the container from the hypodermic needle. A rearward piston is mounted in the rearward end of the container for forward movement therein in slidably sealed relation thereto. A plurality of individual dosages of different relatively incompatible liquid medicaments is disposed within the container between the forward seal and the piston separated by a movable interior seal within the interior of the container between the piston and the forward seal. The improved arrangement is operable in response to the manual accomplishment of the manual actuating procedure and the resultant release of the stressed spring assembly to move the hypodermic needle forwardly and outwardly of the housing assembly into the muscle tissue of a patient and the piston forwardly into the container so that the plurality of individual dosages therein is moved forwardly out of sealed relation with respect to the forward and interior seal outwardly through the needle into the muscle tissue of the patient.

Claims

1. In an automatic injecting device including an elongated housing assembly having a forward end, stressed spring means mounted within said housing so as to be released in response to a predetermined manual actuation procedure, and a medicament injection cartridge assembly mounted within said housing assembly in cooperating relation with said stressed spring means, the improvement which comprises said medicament injection cartridge assembly comprising

a medicament container,

a hypodermic needle disposed forwardly of said container mounted in a sterile condition within said housing assembly adjacent the forward end thereof,

forward seaing means for sealing the forward end of said container from said hypodermic needle,

a rearward piston mounted in the rearward end of said container for forward movement therein in slidably sealed relation thereto,

a plurality of individual dosages of different relatively incompatible liquid medicaments within said container between said forward sealing means and said piston, said plurality of dosages including a forward dosage and a rearward dosage,

movable interior sealing means within the interior of said container between said piston and said forward sealing means maintaining the individual dosages sealingly separated from one another, said interior sealing means comprising an intermediate piston between said forward and rearward dosages mounted for forward movement within said container in slidably sealed relation thereto,

means operable in response to the manual accomplishment of said manual actuating procedure and the resultant release of said stressed spring means for moving said hypodermic needle forwardly and outwardly of said housing assembly into the muscle tissue of a patient and said piston forwardly into said container so that the plurality of individual dosages therein are moved forwardly out of sealed relation with respect to said forward and interior sealing means outwardly through said needle into the muscle tissue of the patient,

said manual actuating procedure responsive means comprising a by-pass bulge in the peripheral wall of said container adjacent the forward end thereof of an axial extent sufficient to enable the forward movement of said rearward dosage to move said intermediate piston forwardly into a by-pass position adjacent the forward end of said container during which said forward dosage is moved forwardly and outwardly through said needle and following which the forward movement of the rearward dosage continues through said by-pass bulge and outwardly through said needle.

2. The improvement as defined in claim 1 wherein said intermediate piston includes a generally cylindrical body of resilient material having a pair of axially spaced forward and rearward annular grooves formed in the exterior periphery thereof, said manual actuating procedure responsive means further including an axial groove formed in the periphery of said cylindrical piston body between the forward annular groove thereof and the forward end surface thereof.

3. The improvement as defined in claim 2 wherein said housing assembly includes a tubular housing member within which said container is mounted for forward sliding movement, said tubular housing member including an axial groove in the interior periphery thereof for receiving said by-pass bulge.

4. The improvement as defined in claim 1, 2 or 3 wherein said forward sealing means comprises a resilient burstable diaphragm disposed in the forward end of said container so as to be flexed forwardly in response to an increase in pressure in the liquid medicament contacting the same, said manual actuating procedure responsive means including piercing edge means disposed forwardly adjacent said diaphragm for insuring that the forward flexure of said diaphragm will result in the bursting of the same.

5. In an automatic injecting device including an elongated housing assembly having a forward end, stressed spring means mounted within said housing assembly so as to be released in response to a predetermined manual actuation procedure, and a medicament injection cartridge assembly mounted within said housing assembly in cooperating relation with said stressed spring means, the improvement which comprises said medicament injection cartridge assembly comprising:

a medicament container,

a hypodermic needle disposed forwardly of said container mounted in a sterile condition within said housing assembly adjacent the forward end thereof,

forward burstable sealing means for sealing the forward end of said container from said hypodermic needle,

a rearward piston mounted in the rearward end of said container for forward movement therein in slidably sealed relation thereto,

forward and rearward individual dosages of different relatively incompatible liquid medicaments within said container between said forward sealing means and said piston,

movable intermediate sealing means within the interior of said container between said piston and said forward sealing means maintaining the individual dosages sealingly separated from one another,

means operable in response to the manual accomplishment of said manual actuating procedure and the resultant release of said stressed spring means for moving said piston forwardly and hence initially the entire cartridge assembly therewith including the hypodermic needle forwardly and outwardly of said housing assembly into the muscle tissue of a patient,

means operable in response to the arresting of the forward movement of the container of said assembly when said needle has been moved into the muscle tissue of a patient and the continued forward movement of said piston within said container for causing said forward burstable sealing means to burst releasing said forward dosage for movement outwardly of said needle by virtue of the forward movement of said intermediate sealing means with respect to said container, and

means operable in response to the forward movement of said intermediate sealing means toward and into a forward limiting position within said container and the continued forward movement of said piston within said container for causing the rearward dosage to move out of sealed relation with said intermediate sealing means and into communication with said needle for movement outwardly thereof in response to the continued forward movement of said piston.