Method and apparatus for constructing subterranean walls comprised of granular material
CA 2260743 C · Owner: Schmednecht, Dana A. · Inventors: Schmednecht, Fred C.; Schmednecht, Dana A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus is provided for producing subterranean walls comprised of granular material. The apparatus comprises a beam for making insertions into and extractions out of the ground. The beam includes a top portion, an open bottom portion, and a hollow interior portion therebetween which receives a supply of granular material. In usage, the beam is inserted into the ground to form a void therein. The apparatus also includes a disposable shoe which is removably attached to the open bottom portion of the beam. In usage, the shoe prevents earthen material from entering the hollow interior portion of the beam as the beam is inserted into the ground. The apparatus further includes an …
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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 February 3, 1999 and granted November 26, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 3, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 3, 2021.
- 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
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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.