Patent · US Expired

Frostproof hydrant seal

US5740831A · kind A · utility

32Cited by
44References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 31, 1996
Grant dateApr 21, 1998
Priority date
Expiry dateDec 31, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/88054
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A sillcock which has freeze resistance, backflow contamination resistance and back pressure release from the downstream water, having a resilient, radially compressible and expandable back pressure seal valve which is also axially movable a controlled amount to thereby cover or uncover an inner vent hole between the water passage and a vent passage, to allow pressure release from the water flow passage to the atmosphere.

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