Flap valve
CA 2039034 C · Owner: Austin, Eric Paul · Inventors: Gardner, Frederick Basil; Austin, Eric Paul
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A flap valve comprising an annular frame (10) defining an opening (11) through which liquid may flow in one direction, a closure flap (14) for said opening connected to the frame (10) by a hinge member (15) and, a valve seat (12) against which the closure flap (14) may close to prevent reverse flow of liquid through the opening. The frame (10) may be bolted (at 18) to a wall or pipe flange, with integral sealing ribs (24 25) on the rear face of the frame avoiding the need for a separate gasket. The entire assembly comprising frame, closure flap, hinge, valve seat and sealing ribs, is integrally moulded from a plastics material and is reinforced where appropriate by embedded steel plates …
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 26, 1991 and granted May 27, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 26, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 26, 2013.
- 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.