Asymmetrical check valve
CA 2247489 C · Owner: Raftis, Spiros G. · Inventors: Abromaitis, A. Thomas; Raftis, Spiros G.; Duer, Michael J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An asymmetrical check valve has an inlet end a, transition part and an outlet end, with a pair of vertical lips facing one another. The lips may be flat or they may be curvilinear. The check valve is asymmetric about a horizontal longitudinal plane through the check valve. The bottoms of the transition part and outlet end may be aligned, with a major portion of the lips extending above the horizontal plane. It is thus possible to install conventional or wide bill check valves in installations with little or no clearance between the outlet end and ground level.
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 September 21, 1998 and granted December 11, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 21, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 21, 2020.
- 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.