Compact self-trimming wingsail
CA 2128724 A1 · Owner: Walker, John Graham · Inventors: Walker, John Graham; Walker, John Graham
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A wingsail assembly comprising at least one rigid thrust wing (1) mounted for free rotation about an upright axis (8). The assembly including means (11) for rotating or translating at least a portion of the thrust wing so as to adjust the location of the instantaneous centre of pressure (9) of the thrust wing with respect to the upright axis. The thrust wing is trimmed by an upwind auxiliary vane (7), freely pivoted upwind of its centre of pressure the angle of attack of the auxiliary vane being controlled by the position of a secondary control aerofoil (15) positioned downwind from the auxiliary vane.
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 January 28, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 28, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 28, 2015.
- 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.