Freeze-free vent
CA 2199754 C · Owner: Davies, John R. · Inventors: Lachapelle, Luc M.; Davies, John R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A flap valve vent hood for discharging air to atmosphere from clothes dryers and bathroom vents is provided freeze-free by a secondary valve that is mounted on the principal flap valve and covering an open area that provides a secondary air flow path through the principal flap valve. The principal flap valve and the secondary valve are normally closed and the principal flap valve is biased to its closed position by gravity. A lip along an edge of the open area may be provided to minimize accumulation of moisture where the two valves are in contact with one another. A soffit vent hood of particular construction is provided in which there are two members detachably interconnected one being a …
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 12, 1997 and granted January 30, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 12, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 12, 2019.
- 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.