Patent · US Expired

Combined check valve and fluid pressure relief valve

US4948092A · kind A · utility

100Cited by
11References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 7, 1990
Grant dateAug 14, 1990
Priority date
Expiry dateMar 7, 2010

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/7882
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A combined check valve and relief valve assembly for permitting the free of a fluid in a first direction and for selectively preventing backflow. Backflow occurs only upon depression of a compression spring-loaded cylindrical valve actuator housed within the valve body. The valve assembly comprises a valve body having an inlet and outlet port which are adjacent to an upper and lower cylindrical bore respectively, thus providing a flow path. A resilient duckbill valve is mounted within the cylindrical bores. A compression spring-loaded valve actuator is also received, lossely, within the valve body and is provided with a stem at the end of the valve actuator, proximate to the opening of the duckbill valve. Fluid passing through the upper cylindrical core around the valve actuator opens the lips of the duckbill valve permitting free passage therethrough. Back pressure seals the lips of the duckbill valve so that the valve becomes a check valve. Depression of the valve actuator, however, causes the stem thereof to penetrate and open the valve lips to selectively permit backflow to provide the relief valve function.

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