A check valve
CA 2120238 A1 · Owner: Horner, Charles Byron Jr. · Inventors: Horner, Charles Byron Jr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A check valve (10) for use in the evacuation of air from a system having primary and secondary disc (32, 34) retained in a chamber of the housing (12) and responsive to first and second forces developed by the creation of a fluid pressure differential between the fluid pressure of air in a first member and a source of vacuum to control the evacuation of air from the member by the source of vacuum. The primary disc is located on a stem (38) that extends from the secondary disc to cover a plurality of openings (42 42') which connect the inlet port (16) to the chamber. A spring (52) holds the secondary disc against the housing. The first force which develops as a result of a pressure …
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 October 9, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 9, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 9, 2014.
- 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.