Transit car power door obstruction sensing system and device
CA 2067594 C · Owner: Mark Iv Transportation Products Corporation · Inventors: Udelhofen, Patrick J.; Flanagan, Daniel J.; Patsch, William J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A system for detecting objects in the path of a power operated, movable door operating in a mass transit vehicle, which would obstruct door closing. The system also includes an integral method for detection of a "free wheeling" door occasioned by failure of the door mechanical drive. Method and apparatus disclosed utilize door handle locating devices such as electrical switches located at predetermined points along the door closure track. A combination of door locations along the closure track centrally define positions signaling either door linkage failure with attendant "free wheeling" door and/or door obstruction, in each case, the system disclosed prevents train motion until the …
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 29, 1992 and granted February 25, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 29, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 29, 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.