Fish ladder for passing dams
CA 2492496 A1 · Owner: Delmer, Boylan · Inventors: Delmer, Boylan
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A safe and effective fish ladder for assisting fish in overcoming dams especially in the upstream direction is described. The ladder comprises a series of relatively vertical open pools which decrease in size in the , upstream direction the pools being conveniently spaced apart a vertical distance which may be easily jumped by the particular fish species of interest. By being arranged relatively vertically so that the downstream , perimeter of one pool is substantially within the downstream perimeter of the pool directly beneath the one pool, the fish ladder does not need to be long and expensive if the dam to overcome is high. Preferred pools in the fish ladder comprise both …
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 24, 2003. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 24, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 24, 2025.
- 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.