Patent · US Expired

Precision reciprocating metering pump

US4808092A · kind A · utility

16Cited by
11References
26Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 6, 1987
Grant dateFeb 28, 1989
Priority date
Expiry dateJan 6, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S417/01
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The pump head liner of a small-size precision reciprocating metering pump, which has its application particularly in High Performance Liquid Chromatography (HPLC), is made of transparent material, preferably of synthetic sapphire or monocrystalline zirconium oxide. A pump head casing is designed such that a pump head liner is visually accessible. Cartridge-type check valve units abut onto the pump head liner on the one side, and onto a connecting adapter piece featuring an elbow liquid duct on the other. Pre-loading pressure for liquid sealing is exerted onto the connecting adapter piece by means of a compression screw which is secured in a clamp bracket or L-shaped angled clamping piece. The cartridge-type check valve units can be composed of transparent components and thereby are visually accessible. The opening and closing of a ball in a check valve unit can be monitored by an optical sensing system in order to obtain a feed-back signal for governing a control circuitry, having the purpose of compensating the influence of the specific compressibility of the liquid being pumped, upon the pumping efficiency of the displacement system under conditions of high and highest working pr…

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