David L Schiessler

US Patent:

53619226, Nov 8, 1994

Filed:

Apr 2, 1993

Appl. No.:

8/042352

Inventors:

Patrick O. Moore - Gilroy CA
David L. Schiessler - Palo Alto CA

Assignee:

Beckman Instruments, Inc. - Fullerton CA

International Classification:

B65D 3900

US Classification:

215364

Abstract:

The present invention directed to a plug for sealing a centrifuge tube. The plug of the present invention is shaped and sized to provide an interference fit between the plug and the tube stem of the centrifuge tube. In the described embodiment, the plug is configured with a tapered body narrowing to a flared end. To facilitate the insertion and removal of the plug with moderate force, without compromising the restraining capability of the interference fit, the area of interference contact between the flared end and the filler stem is strategically reduced. An o-ring is provided in a annular groove around the tapered body. The flared end creates an interference fit with a tapered filler stem, whereby the plug is secured in the filler stem with a snapping action when the flared end of the plug extends into the tube beyond the tapered filler stem. In this snap-in position, the plug is secured in the filler stem, providing an initial seal; such seal increases upon centrifugation by a self-sealing mechanism, either attributed to the internal hydrostatic pressure in the tube and/or the force of a support spacer on the plug. After centrifugation, the snap coupling between the filler stem and the plug securely retains the plug against any residual internal pressure built up within the tube created by deformation of the centrifuge tube either from centrifugation or through handling of the tube by the user.