Device for sealing a conduit against the flow of liquid
US4163458A · kind A · utility
Inventor
Key dates
| Filing date | Mar 18, 1977 |
| Grant date | Aug 7, 1979 |
| Priority date | — |
| Expiry date | Mar 18, 1997 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/4259
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A device, such as a damper or valve, for use in closing a conduit against the flow of liquid has a chamber surrounding and opening into the conduit. A blade at one side of the conduit is movable through the chamber from a first position within a bonnet into a conduit-blocking position. Means carried by the chamber side walls surround the conduit and are between the conduit and the blade when in its first position and are operable then to coact to seal the chamber against leakage into it and to seal the blade when in its second position. At least one seal is of a type brought by fluid under pressure from a position out of the path of the blade into its sealing positions and is carried by the side wall enabling the seal to engage the blade face exposed to the fluid flow. Means are provided to deliver fluid pressure to the pressure operated seal when the blade is in either position and to relieve the pressure therein when the blade is to be moved. Means are also provided to maintain a fluid under pressure in the chamber greater than the fluid pressure in the conduit at least whenever the blade is to move from one position to another and to purge the sealing means and prevent leakage f…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.