Sump-vented controller mechanism for vacuum sewerage transport system
CA 2219218 C · Owner: Featheringill, Burton A. · Inventors: Featheringill, Burton A.; Grooms, John M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An apparatus for preventing waterlogging of the sensor and controller valves used to regulate operation of the vacuum interface valve (162) in a sumpvented vacuum sewerage system. A float valve (250) operates in accordance with the sewage level in a sump pit (154) and communicates atmospheric pressure to the sensor and controller valves while the sewage level is below a predetermined limit, but closes passage of sewage therethrough once the sewage level exceeds the predetermined limit. A pressure-relief valve may also be operatively connected to the float valve (250) that vents excessive hydrostatic pressure buildups in the sump pit (154) to the atmosphere.
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 April 26, 1996 and granted April 24, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 26, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 26, 2018.
- 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.