Patent · US Expired

Tamperproof construction for hydrant actuating nut

US4936336A · kind A · utility

37Cited by
13References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 30, 1989
Grant dateJun 26, 1990
Priority date
Expiry dateOct 30, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/9247
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A tamperproof construction for preventing actuation of the actuating nut of a fire hydrant comprising a nut actuating body for receiving the hydrant nut in turning relationship, set screws locking the nut actuating body to the actuating nut, a shroud permanently secured on the nut actuating body by means of a snap ring so that it covers the set screws but is rotatable on the nut actuating body, a bore in the shroud for permitting selective access to the set screws, a key-operated plug in the bore, a cap permanently and rotatably mounted on an end of the nut actuating body which protrudes through an opening in the shroud, and a limited axial portion of the nut actuating body exposed between the cap and shroud for receiving a specialized wrench.

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