Cartridge interface assembly

Abstract

A cartridge interface assembly ( 80 ) characterized by a driving plunger ( 82 ) including an outer shaft ( 84 ), and a driver ( 86 ) including an inner shaft ( 88 ) moveable telescopically with respect to the outer shaft ( 84 ), wherein rotation of the driver ( 86 ) causes the driving plunger ( 82 ) to advance in a direction away from the driver ( 86 ), and wherein the cartridge interface assembly ( 80 ) is inserted in a cartridge ( 22 ) in which a plunger ( 24 ) is slidingly disposed, and rotation of the driver ( 86 ) causes the driving plunger ( 82 ) to advance distally in the cartridge ( 22 ) until abutting against the plunger ( 24 ).

1 .- 13 . (canceled) 
     
     
         14 . A combination cartridge and cartridge interface assembly comprising:
 a rotationally immobile cartridge ( 22 ) having an inner cylindrical surface, a first stopper ( 24 ) slidingly inserted in the cartridge ( 22 ), a distal end and a substance therein for administration to a subject; and   a cartridge interface assembly ( 80 ) comprising:
 a driving plunger ( 82 ) comprising a first shaft ( 84 ), the driving plunger ( 82 ) having an abutting surface and one or more outer surfaces in contact with the inner cylindrical surface of the cartridge ( 22 ); 
 a driver ( 86 ) comprising a second shaft ( 88 ), said second shaft ( 88 ) mating with said first shaft ( 84 ), so that said shafts are movable telescopically with respect to one another, wherein rotation of said driver ( 86 ) causes said driving plunger ( 82 ) to linearly advance in a direction away from said driver ( 86 ), the arrangement being such that on insertion of the cartridge interface assembly ( 80 ) in the rotationally immobile cartridge ( 22 ), the one or more outer surfaces of the driving plunger ( 82 ) and the inner cylindrical surface of the cartridge ( 22 ) have a frictional relationship such that it is easier for the driving plunger ( 82 ) to move linearly than rotate within the cartridge, wherein the frictional relationship is the only force impeding rotation of the driving plunger ( 82 ) with respect to the cartridge ( 22 ) such that rotation of said driver ( 86 ) causes said driving plunger ( 82 ) to linearly advance only towards the distal end until the abutting surface of the driving plunger ( 82 ) abuts against the stopper ( 24 ) whereupon the driving plunger ( 82 ) urges the stopper ( 24 ) towards the distal end for metering substance from the cartridge; and 
   a locking assembly that permits said driver ( 86 ) to rotate in a first rotational direction and blocks rotation of said driver ( 86 ) in a second rotational direction opposite to the first rotational direction.   
     
     
         15 . The combination according to  claim 14 , wherein said second shaft ( 88 ) is threadedly received inside a hollow portion of said first shaft ( 84 ). 
     
     
         16 . The combination according to  claim 14 , wherein said driving plunger ( 82 ) is at a distal end of said first shaft ( 84 ).