Patent · US Expired

Electromagnet motor control for constant volume pumping

US4150922A · kind A · utility

18Cited by
9References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 23, 1976
Grant dateApr 24, 1979
Priority date
Expiry dateJun 23, 1996

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01L3/0203
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A constant-volume increment pipetting arrangement for use particularly in connection with analysis of minute specimen volumes of biological fluids. The arrangement, which is designed to have a very low inertia factor, comprises a pumping unit having a pair of two-port valves with a duct running between a port from each valve, wherein at least a portion of the duct wall is movable to provide a variable volume pipetting chamber. The second port of one valve serves as the intake port for the fluid to be pipetted and the remaining port of the other valve serves as the delivery port. Three reciprocating drive elements are provided, connected one each to the valves and to the movable portion of the duct wall. Associated with the drive elements is a sequential control means, wherein the control means portion for the drive element connected to the moving portion of the duct wall constitutes an electromagnet arrangement energizable by a periodic supply. Means are associated with the duct wall drive element for controlling the travel amplitude of the electromagnet's armature and thus the travel amplitude of this drive element. The volume of liquid displaced by the movement of the movable por…

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