Patent ID: 7575570

Claim:
An operable syringe assembly having passive disabling structure comprising: a barrel including a side wall having an inside surface defining a chamber for retaining fluid, an open proximal end and a distal end including a distal wall having a passageway therethrough in fluid communication with said chamber; an elongate plunger rod including a proximal end and an open distal end having an interior surface defining a cavity therein, at least one detent on said interior surface at said distal end of said plunger rod, a secondary cavity at a proximal end of said cavity, said secondary cavity having a distal end and a proximal end, said secondary cavity having a contact surface and at least one discontinuity in said secondary cavity; a stopper including a sealing element having a peripheral surface forming a seal with said inside surface of said barrel, a post extending proximally from said sealing element having a proximal end and a distal end, at least two post detents on said post, a secondary post extending axially from said proximal end of said post, having a proximal end and a distal end and at least one discontinuity on its surface, said secondary post being positioned at least partially in said secondary cavity; at least one motion limiting discontinuity on said secondary post positioned to engage said at least one discontinuity in said secondary cavity; and a locking element including a central body portion having an aperture therethrough, at least one cantilevered leg extending distally outwardly from said body portion, and at least one finger element extending proximally inwardly into said aperture, said at least one leg having a sharp free end directed outwardly for engaging said inside surface of said barrel.