Tensionless pier foundation
CA 2205502 C · Owner: Henderson, Allan P. · Inventors: Henderson, Allan P.; Patrick, Miller B.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A hollow, cylindrical pier foundation (10) is constructed of cementitious material (68) poured in situ between inner (12) and outer (14) corrugated metal pipe shells. The foundation is formed within a ground pit (16) and externally and internally back filled. The lower end of the foundation has a circumferential ring (22) fully embedded therein and sets of inner (20) and outer (21) circumferentially spaced bolts have their lower ends anchored to the anchor ring, their upper ends projecting up outwardly of the top of the foundation and a majority of the midportions thereof free of connection with the cementitious material of which the foundation is constructed. The base flange (80) …
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 17, 1995 and granted September 11, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 17, 2015.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 17, 2017.
- 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.