Patent Number: 6,253,628

Title: Apparatus for drawing liquids into and expelling liquids from a pipet at variable flow rates

Abstract: A pipet gun for drawing liquids into and dispensing liquids from a pipet which includes a variable flow valve assembly. The valve assembly includes a valve which is capable of accommodating a plurality of flow rates, and which is progressively adjustable during pipetting between a first air flow rate and a second air flow rate which is in excess of the first flow rate and which is non-progressively adjustable during pipetting to a third air flow rate which is substantially greater than the second air flow rate. The valve assembly further includes a threshold detector in the form of a spring detent, which provides an indication to the operator that the pipet gun is operating at the increased fluid rate, i.e., the "express mode" of operation.

Inventors: Steele; Timothy Paul (Maple Grove, MN), Kenney; James William (Broomall, PA)

Assignee: Becton Dickinson and Company

International Classification: B01L 3/02 (20060101); G01N 001/00 ()

Expiration Date: 07/03/2018