Automatic swing fishway apparatus
CA 2045139 C · Owner: Arakeda, Kunikazu · Inventors: Yokota, Tosiyuki; Arakeda, Kunikazu; Tabuchi, Toshinori
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An automatic swing fishway apparatus comprising a hydraulic chamber provided in a bottom of a waterway which bypasses a dam and a fishway device body comprising a fishway portion provided above the hydraulic chamber and having a floor plate and a plurality of dividing walls provided vertically on the floor plate and a sealed buoyant, portion provided beneath the floor plate. The fishway device body is provided with a main shaft arranged at the downstream end of the fishway device body so that the fishway device body can rotate freely. An overflow weir is provided at the upstream end of the fishway device body and the hydraulic chamber is connected to an upstream end of the fishway device …
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 5, 1990 and granted June 11, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 5, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 5, 2012.
- 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.