Needle-free injector
First Claim
1. In a needle-free injection device for delivering a medicament under pressure from a dosing reservoir through an outlet orifice for administration to an animal or human, of the type comprising a plunger slidably received in said dosing reservoir and movable in a forward direction for expelling said medicament through said orifice, the improvement comprising an actuating device, said actuating device comprising:
- (a) a gas tight chamber;
(b) a piston and rod assembly slidably received in said chamber and movable between a forward position and a rearward position;
(c) a gas charge in said chamber for urging said piston and rod assembly to said forward position;
(d) means for moving said piston and rod assembly against said gas charge into said rearward position; and
(e) a trigger for releasably retaining said piston and assembly in said rearward position,whereby activating said trigger causes said piston and rod assembly to be released for movement by said gas charge to said forward position so as to impact said plunger directly or indirectly with a force sufficient to cause said plunger to move in said forward direction to expel said medicament through said outlet and whereby said gas tight chamber is adapted to minimize or prevent the escape of said gas charge so as to maintain said gas charge in a pressurized state.
2 Assignments
0 Petitions
Accused Products
Abstract
The present invention provides a needle-free injection device for delivering a medicament under pressure into an animal or human. The injection device includes an actuating device comprising: a gas tight chamber; a piston and rod assembly slidably received in the chamber and movable between a forward position and a rearward position; a gas charge in the chamber for urging the piston and rod assembly to the forward position; means for moving said piston and rod assembly against said gas charge into the rearward position; and a trigger for releasably retaining the piston and assembly in the rearward position. Also provided is a method and kit for using the device to administer a liquid through the skin of an animal or human.
101 Citations
23 Claims
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1. In a needle-free injection device for delivering a medicament under pressure from a dosing reservoir through an outlet orifice for administration to an animal or human, of the type comprising a plunger slidably received in said dosing reservoir and movable in a forward direction for expelling said medicament through said orifice, the improvement comprising an actuating device, said actuating device comprising:
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(a) a gas tight chamber; (b) a piston and rod assembly slidably received in said chamber and movable between a forward position and a rearward position; (c) a gas charge in said chamber for urging said piston and rod assembly to said forward position; (d) means for moving said piston and rod assembly against said gas charge into said rearward position; and (e) a trigger for releasably retaining said piston and assembly in said rearward position, whereby activating said trigger causes said piston and rod assembly to be released for movement by said gas charge to said forward position so as to impact said plunger directly or indirectly with a force sufficient to cause said plunger to move in said forward direction to expel said medicament through said outlet and whereby said gas tight chamber is adapted to minimize or prevent the escape of said gas charge so as to maintain said gas charge in a pressurized state. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22)
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23. (canceled)
Specification