Taro Nogami

US Patent:

56519400, Jul 29, 1997

Filed:

Dec 26, 1995

Appl. No.:

8/578452

Inventors:

Val Buonaiuto - Mountain View CA
Taro Nogami - San Jose CA

Assignee:

Hitachi Instruments, Inc. - San Jose CA

International Classification:

B01L 300

US Classification:

422102

Abstract:

The sealing apparatus of the present invention is a sample cuvette cap having a hole for inserting the nozzle of an auto-sampler therethrough. Located within the lumen of the hole is a small detent ball that can be positioned to block the lumen. The detent ball, which can be spring-operated or gravity-operated, blocks the fluid flow in the hole in its normal, closed position. When the auto-sampler nozzle hits the ball, the ball becomes deflected to one side into a recess, due to a difference in the nozzle axis relative to the center of the ball. By the dislocating the detent ball, the nozzle can be inserted into the cuvette smoothly as the air goes in and out through the space around the nozzle. This allows the pressure in the cuvette to be kept constant. After the nozzle is removed, the ball returns to its original position by gravity or by the force of a spring, resealing the cuvette.