Patent ID: 9309042
Filing Date: 2016-04-12
CPC Classification: B65D

Claim Text:
1. A dispensing syringe for use with a pressurized gas, comprising: a barrel having a first end and a second end, and defining an interior reservoir having an inner surface; a piston slidably disposed within the interior reservoir, the piston having a distal end, a proximal end, a generally rigid portion, and an elastic portion, the proximal end configured to receive the pressurized gas and move the piston toward the first end in order to decrease a volume of the interior reservoir proximate to the first end of the barrel and discharge a liquid contained therein, the elastic portion configured to expand under the influence of the pressurized gas; a first circumferentially extending wiper seal positioned on the generally rigid portion of the piston between the distal and proximal ends, the first wiper seal engaging the inner surface such that the first wiper seal liquidly seals against the inner surface and inhibits the liquid within the interior reservoir from flowing proximally beyond the first wiper seal; and a second circumferentially extending wiper seal positioned on the elastic portion of the piston proximally from the first wiper seal, the elastic portion being more flexible than the generally rigid portion such that the elastic portion forces the second wiper seal to contact the inner surface with an increased pressure and an increased surface area to fluidly seal against the inner surface for inhibiting pressurized gas from flowing distally beyond the second wiper seal in order to reduce piston bounce.