Valve for respirator
CA 1268686 C · Owner: Avon Industrial Polymers Limited · Inventors: Angell, Cyril N.E.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A valve for a respirator has an elastomeric valve member of generally dished form with an annular channel around its central portion . The member is secured at its centre by means of a shouldered conical stem and seals round its periphery . The channel allows a sudden collapse of resistance to opening force in the direction of the arrow A above a predetermined amount, but a positive biassing action towards closure. The edges of the channel are slightly axially displaced from one another. Both inlet and outlet valves of a respirator may be equipped with such a 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
- Granted May 8, 1990. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 8, 2007.
- 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.