Patent · US Expired

Sample filtration device

US4891134A · kind A · utility

55Cited by
12References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 25, 1988
Grant dateJan 2, 1990
Priority date
Expiry dateJan 25, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N33/491
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The present invention relates to a sample filtration device of the type employing differential pressure. An outer container filled with a sample to be filtered slidably receives a hollow plunger having filter media disposed near one end and sealing means disposed in an annular groove about the periphery of the plunger. The annular groove of the plunger is formed by two components: an annular shoulder on a collector portion and the axial face of an annular ring formed in a retainer portion. The two portions are frictionally engaged to retain the filter in place and form the annular groove for the sealing means. This construction permits straight-pull molding of the component parts which eliminates mold mismatch flaws.

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