Patent ID: 8287491

Claim:
A syringe assembly comprising: a syringe barrel having an inside surface defining a chamber, an open end, and a distal end; a plunger rod assembly including a stopper, a user interface flange, an elongate body portion extending from said stopper to said flange, a recess along said elongate body portion, and a plurality of first teeth formed within said recess on said elongate body portion, said first teeth defining a plurality of distally facing shoulders, said plurality of distally facing shoulders being equally spaced along a majority of said elongate body portion; and a locking element slidably positioned within said chamber along said majority of said elongate body portion, said locking element engaging said inner surface of said syringe barrel such that said locking element is substantially immovable in the direction of the open end of said syringe band and engageable with said plunger rod assembly such that said plunger rod assembly and locking element are movable distally together toward the distal end of the syringe barrel.