Speed control circuit for an electric motor
CA 1291524 C · Owner: Werner, Paul H. · Inventors: Werner, Paul H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A speed motor control circuit for an electric motor of the type which drives a louvered sign assembly between predetermined rotational positions. The speed control includes a silicon controlled rectifier which is connected in series between the motor and the power supply. A unijunction transistor has one of its bases connected to the gate of the silicon controlled rectifier to switch on or, activate, the silicon controlled rectifier whenever the unijunction transistor becomes conductive. A variable resistor controls the bias to the emitter for the unijunction transistor in order to vary the time period or duty cycle that the unijunction transistor conducts and thus the time period or duty …
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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
- Granted October 29, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 29, 2008.
- 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.