Railway vehicle wheel detector utilizing magnetic differential bridge
CA 2115104 C · Owner: Gilcher, Heinz · Inventors: Gilcher, Heinz
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A differential magnetic wheel detector is disclosed which identifies the presence and direction of a railway vehicle. The wheel detector includes a primary winding, a secondary winding and signal processing circuitry. The primary winding is excited by a source of AC energy to produce a magnetic flux in the wheel of the railway vehicle. The secondary winding senses a change in voltage induced by the magnetic flux in the railway wheel. The secondary winding includes two coils in a differential bridge which prevents external factors from interfering with the sensing of the wheel. The signal processing device transforms the voltage change into a signal identifying the presence and direction of …
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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 7, 1994 and granted April 8, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 7, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 7, 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.