Respirator filtration device
CA 2225986 C · Owner: Metzger, Karl · Inventors: Metzger, Karl
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A novel filtration device having a substantially rigid frame comprised of an outer peripheral band connected by a plurality of spacers to an inner breather tube wherein filter pads, are secured over both sides of the frame and separated by the spacers to form an enclosed central air pocket accessible only through the breather tube. The breather tube is adapted to be detachably connected to an inlet port in a respirator face mask so as to provide a closed channel for air flow from the central air pocket to the interior of the face mask.
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 December 29, 1997 and granted June 25, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 29, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 29, 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.