Railway car truck and method and apparatus for velocity-dependent friction damping
CA 2198545 C · Owner: Hansen Inc. · Inventors: Wright, James F.; Mckisic, Aubra D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Viscous damping such as provided by hydraulic dampers is employed to load frictional energy dissipating elements such as friction wedges used to damp, relative movements between the bolster and the side frames in a conventional railway car truck, such that the magnitude of frictional damping provided is dependent upon the velocity of relative movement between the truck bolster and side frames.
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 February 26, 1997 and granted November 2, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 26, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 26, 2019.
- 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.