Valve having pressure equalizing conduit
CA 2218030 C · Owner: 942648 Alberta Ltd. · Inventors: Domytrak, Walter
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Pressure can build up on one side of a valve bore sealing mechanism when it is closed. This can make the mechanism difficult to open. A bore network is provided which extends through the valve housing side wall from the inlet end of the valve bore to its outlet end. The network bypasses the sealing mechanism and its sealing areas. Needle valves operative from outside the valve, are used to open or close the network. The network can be temporarily opened to enable pressure to equalize across the closed sealing mechanism, thereby freeing the mechanism so that it can be turned.
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 October 10, 1997 and granted April 24, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 10, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 10, 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.