Patent · US Expired

System for dispensing a known volume of fluid

US5316179A · kind A · utility

7Cited by
12References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 20, 1992
Grant dateMay 31, 1994
Priority date
Expiry dateFeb 20, 2012

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF04F1/06
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A system for delivering measured amounts of liquid, such as reagents used in chromatography. Liquid is first moved under gas pressure from a reservoir, such as a reagent bottle, through a valve into a narrow pipe. It reaches a detector which, detecting its presence, closes the valve thus trapping an amount of liquid between the valve and the detector, this amount of liquid then constituting a `unit` or `pulse` of liquid. The movement of the valve is used to connect a gas supply which drives the `unit` or `pulse` out of the pipe to an ultimate destination, such as a chromatographic column. A further `unit` or `pulse` can then be moved into the pipe and this repeated so that delivery to the destination is made in a series of such `units` or `pulse`. By timing the delivery of one `unit` or `pulse`, an amount less than one `unit` or `pulse` can be delivered by passing liquid into the pipe for less than the time taken to deliver one `unit`. This can be used to make up a delivery which is not a unitary multiple of one `unit` or to deliver a small amount of less than one `unit`. No moving parts are involved and delivery of accurately measured amounts is achieved.

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