Cab signal apparatus and method
CA 2136378 C · Owner: Franke, Raymond C. · Inventors: Franke, Raymond C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An apparatus and method for supplying cab signal to a rail vehicle on a section of track composed of sequentially adjacent railway track circuit blocks. Respective receivers of each track circuit block are monitored for the presence of a vehicle within that block. The cab signal apparatus is controlled to transmit a signal to a block when the output from the respective receiver in that block indicates a different condition from the adjacent receiver of an adjacent block. Output voltages from adjacent receivers are compared to enable transmission of a cab signal. Comparison of adjacent receiver outputs is accomplished through use of a diode bridge.
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 November 22, 1994 and granted February 3, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 22, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 22, 2016.
- 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.