Improvements in valves and pumps
CA 2604183 C · Owner: Doig, Ian Dracup · Inventors: Doig, Ian Dracup
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A check valve (10) comprises, a flexible tube (11) having first and second end portions defining an inlet (13) and an outlet (14) respectively, and a rigid , valve body (12) surrounding the flexible tube (11). The end portions of the flexible tube are sealingly fixed to the valve body (12) to define an enclosed space (17) between the exterior of the flexible tube and the interior of the valve body. A fixed volume of a substantially incompressible fluid is located in the enclosed space (17). When the pressure at the outlet (14) is greater than the pressure at the inlet (13), the flexible tube is substantially collapsed so as to close the valve or allow severely restricted flow. …
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 April 11, 2006 and granted February 26, 2013. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 11, 2026.
- Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
- 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.