Patent · US Expired

Seal-free pipette device

US4140020A · kind A · utility

12Cited by
2References
27Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 24, 1978
Grant dateFeb 20, 1979
Priority date
Expiry dateMar 24, 1998

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01L3/0206
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A method and apparatus for measuring a predetermined relatively small volume of liquid from a supply liquid and subsequently dispensing that volume of liquid. A long hollow tube having one end sealed is connected at the other end to an open-ended probe. The long tube is curved into at least one C-shaped segment and is generally rigid along its entire curved length. With the probe tip inserted into the supply liquid, the curved tube is flexed about an axis normal to the plane in which it lies, thereby decreasing the cross-sectional area of the tube. Since the tube is generally rigid along its entire curved length, this flexure of the tube increases the internal volume of the tube thereby reducing the pressure within the tube and withdrawing liquid from the supply liquid into the probe. The amount of liquid withdrawn into the probe is determined by the amount of flexure of the tube. Flexure of the tube in the opposite direction causes the cross-sectional area of the tube to return to its original size thereby decreasing the internal volume of the tube and increasing the pressure within the tube which forces the liquid out of the probe.

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