Valve-talking device
CA 1289036 C · Owner: Nentchev, Valentin N. · Inventors: Nentchev, Valentin N.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A valve-talking device for use in gas masks has two coaxially disposed tubes which are connected together in the front end by a partition that may be a conic expansion of the inner tube. In the space formed between both tubes valves for the exhaled air are mounted. In the portion of the outer tube disposed between the partition and the valves, openings for exhaled air are disposed and the outlet of the front end of the inner tube is closed hermetically by the talking device. The valves for the exhaled air have an annular valve seat and valve membrane which encompass the inner tube.
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 September 17, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended September 17, 2008.
- 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.