Disposable fluid injection module

A drug delivery apparatus, comprising:

• housing means for providing a first chamber therein;
• piston means disposed within said housing means for sliding within said first chamber, said piston means defining a second chamber therein;
• plunger means movably disposed within said second chamber of said piston means for forming a reservoir within the piston means;
• pressure means for forcing said piston means through said first chamber and said plunger means into said reservoir;
• and
• injection means coupled to said plunger means and in communication with said reservoir for delivery of a dose of drug contained within said reservoir.

An apparatus for delivering a drug, comprising:

• a) a housing having a first and second chamber therein;
• b) a piston, positioned within the housing and between the first and second chambers, having a reservoir therein for containing the drug to be delivered;
• c) an injection device, positioned to extend into the reservoir, coupled to the piston and extending into the second chamber, for injecting the drug out of the reservoir;
• and
• d) located in the first chamber, a propellant and an electrical circuit that has a first fusible link for igniting the propellant and thereby delivering the drug.

An apparatus for delivering a drug, comprising:

• a) a housing having a first and second chamber therein;
• b) a piston, positioned within the housing and between the first and second chambers, having a reservoir therein for containing the drug to be delivered;
• c) an injection device, positioned to be extended into the reservoir and out of the housing, for delivering the drug out of the reservoir;
• and
• d) a biasing device, located proximate the piston, for retracting the injection device into the housing after the drug has been delivered.

An apparatus for delivering a drug, comprising:

• a) a housing having a distal end through which the drug is delivered and a proximal end and defining a first chamber therein;
• b) a piston disposed within said first chamber, said piston defining a second chamber therein;
• c) a piston core movably disposed within said second chamber of said piston and defining a reservoir between said piston and said piston core;
• d) a pressure source proximate said proximal end and in communication with said first chamber;
• e) an injection device coupled to the piston core and in communication with said reservoir for delivery of a dose of a drug contained therein;
• f) a biasing device disposed in the chamber and contacting the piston core for biasing said injection device toward said proximal end;
• g) an end cap attached to said distal end of said housing;
• and
• h) the biasing device is a spring interposed between said end cap and said piston core.

An apparatus for delivering a drug, comprising:

• a) a housing having a distal end through which the drug is delivered and a proximal end and defining a first chamber therein;
• b) a piston disposed within said first chamber, said piston defining a second chamber therein;
• c) a piston core movably disposed within said second chamber of said piston and defining a reservoir between said piston and said piston core;
• d) a pressure source proximate said proximal end and in communication with said first chamber;
• e) an injection device coupled to the piston core and in communication with said reservoir for delivery of a dose of a drug contained therein;
• f) a biasing device disposed in the chamber and contacting the piston core for biasing said injection device toward said proximal end;
• and
• g) an end cap attached to said distal end of said housing, the end cap includes a curved wall defining a channel therein for encouraging said injection device to bend at an angle relative to a longitudinal axis of said injection device.

A drug delivery apparatus, comprising;

• a) housing means for providing a first chamber therein;
• b) piston means disposed within said housing means for sliding within said first chamber, said piston means defining a second chamber therein;
• c) plunger means movably disposed within said second chamber of said piston means for forming a reservoir within the piston means;
• d) pressure means for forcing said piston means through said first chamber and said plunger means into said reservoir;
• e) injection means coupled to said plunger means and in communication with said reservoir for delivery of a dose of drug contained within said reservoir;
• f) the pressure means includes gas generating means for creating a gas and initiating mans for introducing said gas into said first chamber;
• and
• g) the initiating means is an electrical circuit comprising an electrical source and a fusible link, said electrical source providing electrical current to heat said fusible link and ignite said propellant.

A drug delivery apparatus, comprising:

• a) housing means for providing a first chamber therein;
• b) piston means disposed within said housing means for sliding within said first chamber, said piston means defining a second chamber therein;
• c) plunger means movably disposed within said second chamber of said piston means for forming a reservoir within the piston means;
• d) pressure means for forcing said piston means through said first chamber and said plunger means into said reservoir;
• e) injection means coupled to said plunger means and in communication with said reservoir for delivery of a dose of drug contained within said reservoir;
• and
• f) the adjustment means includes adjustable stop means associated with said plunger means for stopping movement of said piston means upon activation of said pressure means.