Gun type hypodermic injector with rapid cartridge displacement within holder

Claim 2

A cylindrical cartridge holder and cartridge for use with a gun having a plunger for cooperation with said cartridge, said cartridge holder including means for positioning the holder in operative relationship with respect to the plunger, said holder being closed off at one end thereof, the cartridge comprising a cylindrical ampoule and fixedly attached cannula and fitting completely and movably within the holder with the cannula facing the closed holder end, said ampoule having an outer diameter less than the inner diameter of the cylindrical holder to form an annular space therebetween, sealing means on the inner surface of the cylindrical holder remote from its closed end and in engagement with the outer surface of the ampoule sealing the aforesaid annular space between the ampoule and holder at the ampoule end opposite the cannula whereby upon movement of the ampoule from the sealed position toward the closed end of the holder the seal is broken and free passage of gaseous fluid from in front of the ampoule to the rear thereof is provided by the aforesaid annular space.

Claim 3

The invention as set forth in claim 1 and wherein the ampoule is provided with a piston seal at its end opposite the cannula and a liquid is contained in the ampoule between the cannula and the piston.

Claim 4

The cartridge holder and cartridge of claim 2 in combination with a gun, said gun having an inner sleeve aligned with the holder and an outer sleeve telescopically engaged with the inner sleeve and having means to fire the gun when telescoped.

Claim 5

The combination as set forth in claim 3 in which the gun includes a plunger, and in which the inner wall of the inner sleeve is provided with ribs running longitudinally of the sleeve to guide the plunger toward the piston.

Claim 6

A cartridge holder as set forth in claim 1 in which the ampoule includes a piston at one end thereof and a fluid in the ampoule between the piston and cannula and in which the ampoule also includes a diaphragm at the end thereof remote from the piston, said diaphragm being made of a material to allow passage of fluid therebeyond upon sufficient pressure being applied to the fluid by the piston.

Claim 7

A hypodermic injection device comprising in combination, a gun, a cartridge holder fixed in operative relationship to the gun and a cartridge including an ampoule with attached cannula within the holder, said gun having a sleeve open at one end thereof, a plunger within the sleeve, potential energy means acting on said plunger tending to move it out of the open end of the sleeve, restraining means cooperative with said plunger to prevent plunger movement, safety means acting on said restraining means to render it inoperative, said cartridge holder comprising a cylindrical shell acting as a prolongation of said gun sleeve, said shell at a free end thereof being closed off by a puncturable seal, annular sealing means on the interior portion of the shell remote from the closed end, said cartridge comprising a cylindrical ampoule with a piston forming a seal in one end thereof, a fluid within said cylinder, the cannula affixed to the end of the cylinder opposite the piston, the cartridge, as a whole, movably fitting within the holder with the free end of the cannula within the holder at the closed-off end and the end, only, of the cartridge remote from the cannula held in sealing engagement with sealing means on the interior portion of the holder shell to allow free passage of gaseous fluid from the advancing end of the cylinder to the rear end thereof as the cartridge is translated relative to the holder.

Claim 8

A hypodermic injection device comprising in combination, a gun, a cartridge holder fixed in operative relationship to the gun and a cartridge including an ampoule with attached cannula within the holder, said gun having a sleeve open at one end thereof, a plunger within the sleeve, potential energy means acting on said plunger tending to move it out of the open end of the sleeve, restraining means cooperative with said plunger to prevent plunger movement, safety means acting on said restraining means to render it inoperative, said cartridge holder comprising a cylindrical shell acting as a prolongation of said gun sleeve, said shell at a free end thereof being closed off by a puncturable seal, annular sealing means on the interior portion of the shell remote from the closed end, said cartridge comprising a cylindrical ampoule with a piston forming a seal in one end thereof, a fluid within said cylinder, the cannula affixed to the end of the cylinder opposite the piston, the cartridge, as a whole, movably fitting within the holder with the free end of the cannula within the holder at the closed-off end and the end, only, of the cartridge remote from the cannula held in sealing engagement with sealing means on the interior portion of the holder shell to allow free passage of gaseous fluid from the advancing end of the cylinder to the rear end thereof as the cartridge is translated relative to the holder.

Claim 9

The device of claim 6 wherein the ampoule further includes a diaphragm at the end thereof opposite the piston, said diaphragm being made of a material to allow passage of fluid therebeyond upon sufficient pressure being applied to the medicament by the piston.

Claim 10

The invention as set forth in claim 6 and wherein the gun plunger is provided with a head portion having a plurality of radially extending tabs adapted to engage the ampoule cylinder at its piston end.

Claim 11

The invention as set forth in claim 8 and wherein the plunger head is sized to fit within the ampoule cylinder.

Claim 12

The invention as set forth in claim 6 and wherein the gun and the cartridge holder with the cartridge therein are assembled within a single cylindrical housing.

Claim 13

The device of claim 6 and wherein ampoule engaging means are interposed between the gun plunger and the piston end of the ampoule whereby actuation of the gun plunger forces the ampoule engaging means and the ampoule to be moved toward the closed end of the cartridge holder.

Claim 14

The device of claim 11 and wherein abutment means are provided whereby upon prescribed movement of the ampoule the ampoule engaging means are disengaged from the ampoule and the gun plunger then continues to move forward pushing the piston ahead of it to eject the ampoule fluid.

Claim 15

The device of claim 8 and wherein the tabs are integral with the head portion and have weakened portions to provide for deflection, and further wherein abutment means are provided on the cartridge holder whereby upon prescribed movement of the ampoule the abutment means stop the travel of said ampoule and continued movement of the gun plunger causes the tabs to be disengaged from the ampoule whereupon the gun plunger continues its travel pushing the ampoule piston ahead of it to eject the ampoule fluid.