External valve operating means
CA 2247134 A1 · Owner: Henry Valve Company · Inventors: Scapes, John N.; Gugala, Zbigniew H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An external valve operating means (51) that forms a seal (71) around the rotating valve stem (11) of a valve (3) operating under internal pressure is disclosed. This seal (71) prevents the escape of fluids should the valve's primary seals (29, 37) fail. The external valve operating means (51) allows for rotation of the valve stem (11) without removal or compromise of the seal. A stationary operating seal cap (53) is in threaded and sea led engagement with the valve body (5). Upon partial disengagement of the stationary operating seal cap (53), the pressure within the external valve operating means (51) is vented. An external valve stem drive (63) protrudes through the top of the …
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 January 8, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 8, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 8, 2019.
- 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.