Patent · US Expired

Manhole insert and tether and method

US5727351A · kind A · utility

30Cited by
20References
24Claims
0Family size

Inventors

Key dates

Filing dateOct 20, 1994
Grant dateMar 17, 1998
Priority date
Expiry dateOct 20, 2014

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T292/1071
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A watertight manhole insert and tether apparatus designed to prevent rainwater from entering sanitary sewer or other systems through a manhole closed by a manhole cover. The manhole insert is located beneath the manhole cover and is connected directly to the manhole by a tether mounted in the manhole, to plug the manhole and prevent theft of the manhole insert. The manhole insert is characterized by a pan-shaped insert body having a flat insert bottom and a pressure-relief valve, one or more lift straps optionally provided with a warning tag, and an upward-standing, sloping or perpendicular side wall fitted with an outwardly-extending top rim for engaging a shoulder shaped in the manhole to support the manhole insert. One end of the flexible stainless steel tether is connected to the manhole wall and the opposite end first extends through a grommet in the insert bottom and subsequently through a lever bar locking device. According to the method of this inventory when the manhole insert is placed in the manhole, the tether is pulled upwardly through the grommet and the lever bar locking device is slipped along the tether and locked at the insert body to seat the manhole insert on th…

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