Impeller annular seal
CA 2063624 C · Owner: Warman International Ltd. · Inventors: Walker, Craig Ian
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Centrifugal pumps suffer from wear of the annular seal (1) between the impeller (2) and the casing or side liner (3), due to the returning flow of the rejoining fluid (9). The present invention ameliorates this problem by having the clearance of the annular seal (10, 11) at least adjacent the inlet (6) of the impeller (2) sloping, in the direction of the main fluid flow (7) into the impeller inlet (6) at an, angle of between 0À and 60À to the axis of rotation of the impeller (2).
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 March 20, 1992 and granted February 19, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 20, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 20, 2014.
- 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.