Valve stem sealing means for prevention of fugitive emissions
CA 2050101 A1 · Owner: Icenhower, John D. · Inventors: Horvath, Stephen M.; Icenhower, John D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A valve stem sealing means comprising first and second seal assemblies, the first seal assembly being proximate a valve plug and comprising an expandable ring adapted to be expanded by pressure within the valve to effect a first seal around the valve stem, and the second seal assembly being nearer a free end of the valve stem and comprising a second expandable ring adapted to be expanded by contact with a selectively movable member to effect a second seal around the stem.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed August 28, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 28, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 28, 2013.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.