Well casing protector
CA 2254982 A1 · Owner: Hart, John · Inventors: Hart, John
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to protectors which protect well casings against frost heaving forces. In the invention, a well casing protector having a cavity extend though, its entire length is provided. The cavity is shaped to slide over the end of a well casing. The well casing protector is able to slide up or down along the well casing. Once in, place, the well casing protector surrounds the portion of the well casing extruding from, the ground (except for the very top portion of the well casing) and also the portion of, the well casing in the portion of the ground just beneath the ground surface which, freezes. Because the well casing protector is slidable along the well casing unit, …
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 November 30, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 30, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 30, 2020.
- 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.