Patent ID: 6077713
Filing Date: 2000-06-20
Classification: G01N,Y10T

Abstract:
A method for extracting a desired quantity of liquid from the interior of a container closed with a penetrable closure comprising the steps of:(a) placing the container within the interior of a sealed telescoping chamber, said chamber having:a lower portion adapted to support a cannula within the chamber and to position the penetrable closure at the cannula, andan upper portion adapted to force the penetrable closure over the cannula when the upper portion is moved over the lower portion;(b) establishing pneumatic communication between the chamber and a pressure transducer and pressure control means;(c) initiating penetration of the closure with the cannula by closing the telescoping chamber, said cannula having a passage extending the length of the cannula and a groove extending a partial length of the cannula;(d) operating the pressure control means in response to the transducer so as to maintain a constant pressure range within the chamber;(e) continuing penetration of the closure with the cannula until the groove establishes open communication between the interior of the chamber and the interior of the container, thereby forcing liquid from the tube through the passage; and,(f) opening the valve after the desired quantity of fluid has been forced from the container.