Patent ID: 9592346
Date: 2017-03-14
CPC Classifications: A61M

Claim:
1. A stopper adapted for attachment with a plunger rod for use within a syringe barrel, said stopper comprising: (a) a main body defining an open rearward end and a closed front end, said open rearward end adapted to receive a front forward end attachment portion of such plunger rod; (b) a core member integrally formed with said main body adjacent said closed front end, said core member including a nose portion and a stopper center post protruding from an interior of the core member toward the open rearward end, said stopper center post including a back core portion adapted for contact with said front forward end attachment portion of the plunger rod; (c) at least one rib extending radially outward around a perimeter of said main body for forming an active seal with such syringe barrel; and (d) an inward shoulder portion on an inner surface of said main body, said inward shoulder portion adapted for contact at a contact point with a taper on a forward end of the plunger rod, wherein contact of said inward shoulder portion with said taper causes the stopper to apply a radial force to said at least one rib and the syringe barrel upon the application of a forward force to the plunger rod, and wherein said inward shoulder portion includes a first cylindrical wall portion extending from the closed front end of said main body to the contact point, said first cylindrical wall portion having a substantially flat surface profile that is substantially uniform and non-tapered along its longitudinal length.