Dual check valve
CA 2016277 C · Owner: Mueller Co. · Inventors: Sands, Robert E.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A valve housing is provided with an, interior passage therethrough with the passage having two spaced apart valve seats; a first check valve member for engaging the first valve seat has a valve stem movably carried in a hollow shaft; the second valve member is itself provided with a tubular stem having an open end and which is slidably fitted on the exterior of the hollow shaft; separate coil springs are provided for urging each valve member toward a closed position on the respective valve seat whereby the each valve member is operable independently of the other valve member.
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 May 8, 1990 and granted August 17, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 8, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 8, 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.