Disposable hypodermic injection ampule
First Claim
1. In a needleless hypodermic injector operable by propellant gas generated from the detonation of an explosive charge, a disposable ampule comprising:
- an elongated casing having an axial bore therein, said bore including an inwardly tapered portion at one end of said casing terminating in a fine orifice through said casing;
a cavity in said casing containing a propellant charge and in communication with said bore at the opposite end of said casing;
a gas-operated piston slidably and sealingly mounted in said bore for sliding axial movement therein in the direction of said orifice upon detonation of said charge, said piston having a tip portion conforming closely to the inwardly tapered portion of said bore;
a rupturable sealing member positioned in said tapered portion of said bore nearer said orifice, and with said piston defining a chamber in said bore for a measured dose of injectant fluid, said sealing member including means adapted to rupture under pressure exerted by said fluid in response to axial movement of said piston upon detonation of said charge, and to retrovert and deform into an hermetic seal between the tip portion of said piston and the inwardly tapered portion of said bore.
1 Assignment
0 Petitions
Accused Products
Abstract
A self-contained disposable explosively actuated ampule for performing needleless percutaneous injection. The ampule comprises an outer shell enclosing an elongated inner chamber including a closed rear end containing a propellant charge, a tapered funnel-shaped forward end, and a scored sealing member hermetically sealing the chamber in the area of its funnel shaped end. A metered dose of fluid injectant is confined between the scored sealing member and a sealing plunger separating the injectant from the charge. The plunger is adapted for axial movement within the chamber and comprises a main body having sealing means thereabout which are compressed and tightened against the inner chamber wall, and having a tip portion projecting forwardly from the main body. Gas released at very high pressure by the charge drives the plunger in the chamber and pressurizes the fluid injectant, thereby causing the scored sealing member to rupture and enabling the fluid to be discharged from the chamber forward end. Simultaneously, the outer circumferential surface of the plunger tip sealingly abuts the inner peripheral surface of the chamber forward end. The sealing elements in the plunger main body are comprised of an annular feather-edge seal around the rear end of the plunger and annular sealing means about the axial main body of the plunger.
168 Citations
13 Claims
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1. In a needleless hypodermic injector operable by propellant gas generated from the detonation of an explosive charge, a disposable ampule comprising:
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an elongated casing having an axial bore therein, said bore including an inwardly tapered portion at one end of said casing terminating in a fine orifice through said casing; a cavity in said casing containing a propellant charge and in communication with said bore at the opposite end of said casing; a gas-operated piston slidably and sealingly mounted in said bore for sliding axial movement therein in the direction of said orifice upon detonation of said charge, said piston having a tip portion conforming closely to the inwardly tapered portion of said bore; a rupturable sealing member positioned in said tapered portion of said bore nearer said orifice, and with said piston defining a chamber in said bore for a measured dose of injectant fluid, said sealing member including means adapted to rupture under pressure exerted by said fluid in response to axial movement of said piston upon detonation of said charge, and to retrovert and deform into an hermetic seal between the tip portion of said piston and the inwardly tapered portion of said bore. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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Specification