Patent · US Expired

Basket type core retainer

US3952817A · kind A · utility

8Cited by
9References
16Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 8, 1974
Grant dateApr 27, 1976
Priority date
Expiry dateMar 8, 1994

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B25/10
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

Basket type core retainer apparatus that includes a core receiving tube having an axially inner end, an annular drill bit or tubular extension connected to the inner end of the core receiving tube and a core retainer cooperatively mounted by the tube and the bit or tubular extension to permit passage of core into the tube and retain a core or a soil sample in the tube. The core retainer includes a mounting ring that mounts a pair of spring finger assemblies to extend axially outwardly thereof. The finger assemblies are each formed from a single sheet of material, the fingers of the assemblies in a closed (core retaining) position having each finger of one assembly in partial overlapping relationship to an adjacent finger of the other assembly and in partial underlapping relationship to an adjacent finger of said other assembly. The fingers are movable to permit passage of a core or a soil sample into the receiving tube.

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