Motor control apparatus for a railway switch machine
CA 2396618 C · Owner: Franke, Raymond C. · Inventors: Bozio, Robert P.; Franke, Raymond C.; Wydotis, Leonard M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A motor control apparatus (104) for a railway switch machine (106) includes a power source (134) for a voltage; a selector (132) for providing the voltage to a reversible motor (105) of the switch machine (106) in a normal state and , for providing a reverse polarity of the voltage to the reversible motor (105) in a reverse state; a first transistor (129) for switching reverse current flowing through the reversible motor (105); a first diode (131) electrically connected in parallel with the first transistor (129) for conducting normal current for the reversible motor (105); a second transistor (128) for switching normal current flowing through the reversible motor (105); a second …
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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 January 23, 2001 and granted June 3, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 23, 2021.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 23, 2023.
- 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.