Closure for air evacuated container
AssigneeBecton, Dickinson and Company
InventorEdward P. Percarpio
Life of this patent
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Abstract
The disclosure is of a novel closure for air evacuated tubular containers and comprises a tubular body having flexible, elastic sidewalls, an open end, a closed end formed by a cannula-pierceable, flexible, elastic end wall having a concavo-convex configuration in cross-section and a flange disposed radially about the periphery of the open end. The novel closure structure takes advantage of the vacuum force in the container to maintain a gas-proof, hermetic seal, reduces the thickness required of the closure to maintain the hermetic seal and is easier to assemble in an air evacuated container. The disclosure is also of a novel method of assembling the closure of the invention in an air evacuated tubular container.
Claims7
A cannula-pierceable, self-sealing, gas-proof closure for sealing an open end of an air evacuated blood collection tube, which comprises;
- (a) a tubular elastomeric body having
- (i) flexible, elastic sidewalls;
- (ii) an open first end;
- and
- (iii) a closed second end formed by a cannula pierceable, flexible, elastic end wall integral with said sidewalls;
- and
- (b) a flange disposed radially about the periphery of said sidewalls adjacent to said first end;
- said end wall having a convex inner surface and a concave outer surface when pressure on inner and on outer surfaces is equal, said tubular body having a diameter which bears a ratio to the height of the body of about 0.8:1 and to the thickness of the second end of from 5.4:1 to 12.1:1;
- whereby when the closure is emplaced in and sealing an open end of an air-evacuated tube, the higher pressure on the convex inner surface of the end wall as compared to the lower pressure (vacuum) exerting itself on the concave outer surface creates a pressure differential on the end wall, flexing and flattening the concavo-convex configuration and creating a radial force directed toward the periphery of the end wall, said force affecting a restraining and sealing force between the closed second end of the elastomeric body and the air-evacuated tube.
Dependencies are inferred from the claim text.