Patent ID: 7731678

Claim:
A syringe device comprising: a syringe body comprising a cylindrical housing and a chamber within the housing, the chamber having a longitudinal axis; a piston comprising a stem, a longitudinal axis, a first end at a first end of the longitudinal axis and a second end opposing the first end, the first end being external to the chamber, the piston comprising a first opening at the first end and a second opening at the second end; a fluid passageway extending through the first opening, longitudinally through the stem and through the second opening of the piston; a third opening disposed along the longitudinal axis at a position between the first end and the second end of the piston other than at the first or second end of the piston and traversing the fluid passageway; a valve, at least a portion of which is inserted within the third opening and orthogonally traversing the fluid passageway, the valve controlling selective fluid passage through the piston and being at least partially insertable within the cylindrical housing of the syringe body; a piercing structure associated with the first end of the piston, the piercing structure a base having a first diameter, a head portion having a maximum width, and a tube segment extending between the base and the head portion, the tube segment having a second diameter that is smaller than the first diameter and shorter than the maximum width of the head portion; and a piston seal attached to the second end of the piston.