Geotextile for detection of backfill level
CA 2204174 A1 · Owner: Demers, Lester · Inventors: Demers, Lester; Despaux, Valerie
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a geotextile material that makes it possible to measure the thickness of a layer of backfill covering it. The material performs the functions of a geotextile and makes it possible to measure the level of backfill using equipment designed for this purpose. Such a geotextile can be manufactured by needle-punching synthetic fibres through continuous metal sheets maintaining a number and dimension of perforations that always allows for detection. Another method would consist in laminating to the geotextile perforated or non-perforated metal sheets that can be detected.
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 30, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 30, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 30, 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.