Air concentrator
CA 2045659 C · Owner: Piggott, Keith · Inventors: Feuerriegel, Raymond John; Piggott, Keith
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An air concentrator for dry separation of gold and other heavy minerals from alluvial deposits comprises a housing (50) having a number of open-topped chambers (52) arranged in a ring-like configuration and surmounted by a screen (14) having rings (39 41) thereon forming annular, screen beds (36). A wiper bar assembly consisting of a number of wiper arms (6,7) radiating from a hub (1, 2) sweeps over the screen beds (36). Air under pressure is fed sequentially and cyclically to the chambers (52) by a rotary valve (28) located centrally of the ring of chambers. The deposit is fed over the hub (1, 2) and is swept outwardly over the beds (36) on the screen (14) by the wiper arms (6, 7), where …
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 February 12, 1990 and granted April 11, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 12, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 12, 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.