Patent · US Expired

Portable automated pipette for accurately pipetting and/or titrating liquids

US4905526A · kind A · utility

49Cited by
12References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 8, 1987
Grant dateMar 6, 1990
Priority date
Expiry dateJun 8, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T436/2575
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A hand held self-contained automated pipette for portable operation having an electrically operated digital linear actuator. The actuator preferably includes a stepper motor driving a rotor. A threaded screw is coaxially positioned within the rotor and is connected to an actuator shaft having elongate grooves slidable in a guide for preventing shaft rotation so that precise linear motion is imparted to the shaft. A pipetting displacement assembly having one of various sizes is removably attached for actuation by a common actuator including programmed movement of a displacing piston in a displacement cylinder to optimize air interface volume, neutralize variations in vacuum pipette effects, and provide an accommodated stroke and readout for improved accuracy while pipetting and/or titrating different ranges of volumes. Upon calibration the piston undertakes immediate excursion to an end of travel limit and after motor slippage is retracted to a home position. This home position is chosen for optimum preservation of an air interface volume between drawn liquid and the piston tailored with particularity to the displacement assembly being used. Multiple precision modes, including pipet…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.