Patent · US Expired

In-line back flow preventer

US4420010A · kind A · utility

7Cited by
15References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 7, 1980
Grant dateDec 13, 1983
Priority date
Expiry dateMar 7, 2000

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/863
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A device for preventing the back flow of water from a point of use into a water supply line. The device includes a unitary casing having an inlet, a central chamber, an outlet, a removal port and a drain vent opening. The inlet, the central chamber and the outlet are coaxially aligned. A relief valve is located in the central chamber and offset from the coaxial alignment of the inlet, the central chamber and the outlet. There is a cover for the removal port. There is also a pair of check valves. One is mounted between the inlet and the central chamber and the other is mounted between the outlet and the central chamber. The device allows water to pass unobstructed in a straight-through flow path through the device. The back flow of water is prevented.

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