Culvert end wall retainer system
CA 2129191 C · Owner: Goodreau, Eugene Alfred · Inventors: Goodreau, Eugene Alfred
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Pre-fabricated end wall for culvert includes a novel pre-cast concrete slab shaped with an upper margin longer than the lower margin and with inclined side or end margins which are proximate the angle of repose of the culvert or ditch in which the culvert end walls are to be inserted. Each end wall defines an aperture into which mates or nests a conduit which is adapted to pass water from one end wall through the other end wall. Backfilling is the usual aggregate is compacted into and between the end walls to complete the culvert structure and if desired a roadway, surface may be placed over top of the same.
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 July 29, 1994 and granted November 17, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 29, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 29, 2016.
- 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.