Underground drain tank
CA 2132799 A1 · Owner: Wiebe, David K. · Inventors: Wiebe, David K.; Horn, Donald G.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A drain tank for installation underground has a longer life than steel and fibreglass tanks and has a leak detection system to identify leaks. The drain tank comprises a sealed concrete chamber having at least one opening at the top thereof with a collar integral therewith, a manway connected to the collar extending upwards, the manway having a top lid with a vent and pump out exit. Inside the concrete chamber is an impervious flexible bag liner which is sealed to the collar; an entry pipe passes through the chamber and the liner and a leak detector tube passes down into the chamber to a location at the base between the chamber and the liner for an insertion tube to pass therethrough.
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 September 23, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 23, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 23, 2016.
- 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.