Method of filling an excavated opening
CA 2224277 C · Owner: Bg Plc · Inventors: Owen, Raymond Caulton
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An excavated opening (10) through a pavement (12) of a highway and through the underlying base material (14) to expose a gas main (16) is filled by (i) mixing on site cement, foaming agent and water to produce a fluid grout (26) (ii) mixing the grout with loose excavated spoil (22) in the opening (iii) , agitating the mixture using a hand-held poker vibrator (30) (iv) and , repeating this procedure until the level (40) is reached. The level (40) corresponds to the underside of a protective layer (50) which is subsequently applied. The majority of the excavated loose spoil from the opening is reused.
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 June 21, 1996 and granted September 4, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 21, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 21, 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.