Rail navigation system
CA 2175776 C · Owner: Woodward, Roger P. · Inventors: Woodward, Roger P.; Kull, Robert C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Method and apparatus for a railway navigation system which provides information defining the position of a railway vehicle on a track system. The system uses an on-board computer with a track database representing the locations of the rail lines including locations of curves and switches. The system uses a turn rate indicator and a speedometer means to obtain a value for the curvature of the track on which the railway vehicle moves. Curvature data so obtained is compared with data in the track database to determine the position of the railway vehicle in relation to curves and switches of the track system.
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 May 3, 1996 and granted January 16, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 3, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 3, 2018.
- 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.