Syringe assembly having a disabling mechanism with characteristics of resistance to manipulation.

摘要

A set of operating syringe (200) having a structure of passive disabling comprising: a cylinder (202) including a cylindrical side wall (206) having an inner surface (207) defining a chamber (209) for retention fluid, an open proximal end (213) and a distal end (215) including a distal wall (217) having a bore (219) therethrough in fluid communication with said chamber; an elongated shaft (208) of plunger having a proximal end (211), an open distal end (210) including a side wall (212) having an inner surface (216), at least one detent (218) in said inner surface (216); a stop (228) which includes a sealing element of circular shape (229) having a peripheral surface (231) forming a seal with said interior surface (207) of said cylinder (202), a member of projection (232) projecting proximally from said sealing element (229), at least one detent (233) projecting into said boss (232), a retaining element (234) connected to said stop (228) by a frangible connection ( 235) and defining an axial recess (237) having a proximal projection (239) for accepting said positioning lug (220) of said plunger (208) and to limit axial movement of said positioning lug (220) said recess in axial (237); one locking element (130) including a central portion (148) body having an opening (152) therethrough, at least one cantilevered leg (150) extending distally outwardly from said portion (148) body, and at least one finger element (154) extending proximally inwardly from said aperture (152), said at least one cantilevered leg (150) has a sharp free end ( 155) directed outwardly for engaging said inside surface (207) of said cylinder (202); said locking element (130) is positioned with said sharp free end (155) in contact with said inner surface (216) of said stem (208) of proximal piston relative said at least one detent (218), said member projecting (232) is placed in said opening (152) of said locking element (130) in said at least one finger element (154) is in contact with said protrusion (232) proximal of said at least one detent (233) projecting, so that application of a force directed proximally to said stem (208) piston direction while said cylinder (202) is held causes said rod (208) plunger to move proximally with respect to said stop (228) until said free end (155) of said cantilevered leg (150) moves distally along said inner surface (216) of said rod (208) piston to said at least one detent (218) and said proximal face (222) of said positioning lug ( 220) contacts said shoulder proximal (239) of said retainer (234) to move said stop (228) in proximally a certain distance, and subsequently applying a force directed distally to said stem (208 ) piston for discharging liquid from said chamber (209) through said conduit (219) causes said rod (208) piston to move distally along with said locking element (130) due to its engagement with said at least one detent (218) until said finger element (154) of said locking element (130) rises above said at least one detent (233) of outgoing and contacts said at least one detent (233) outgoing and said rod (208) piston contacts said stop (228) to move said stop (228) distally to discharge fluid from said chamber (209), whereupon the application of force proximally directed said rod (208) will cause piston said rod (208) piston to move proximally until said free end (155) of said cantilevered leg (150) moves distally along said inner surface (216) beyond said distal end ( 210) of said rod (208) piston to said sharp free end (155) of said at least one cantilevered leg (150) engages said inner surface (207) of said cylinder (202) to help prevent proximal movement of said stopper (228) for causing said syringe assembly (200) unusable, characterized in that said side wall (212) of said elongated shaft (208) of the plunger has an axial opening (214) and a lug placing (220) projecting toward said opening (214), said pin (220) has a distal face (221) and a proximal face (222); said retaining element (234) is connected with the sealing element (229) of the stop (228).