Freight brake control valve having improved quick service function
CA 2014685 C · Owner: Westinghouse Air Brake Company · Inventors: Hart, James E.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A freight brake control valve device fo a railway vehicle having a service piston slide valve arranged with a detent to latch the service piston in preliminary quick service position until such time as the application pressure differential acting on the piston exceeds a predetermined value.
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 April 17, 1990 and granted January 21, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 17, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 17, 2012.
- 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.