Brushless dc motor
CA 2045007 C · Owner: Gotou, Makoto · Inventors: Inaji, Toshio; Gotou, Makoto
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is a brushless DC motor which does not have a position sensor for detecting a rotational position of the rotor in which conducting phases of the stator windings to be detected are subsequently selected by multi-phase selection signals in response to a conducting state of the stator windings then a, pulse signal train is generated by detecting the counter electromotive forces induced in the conducting phases subsequently selected and a trapezoidal waveform signal is formed by a slant waveform signal generated in response to the pulse signal train thus obtained. Furthermore, with the trapezoidal waveforms signal thus formed as position signal of the rotor an electric, current signal …
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 June 19, 1991 and granted August 20, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 19, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 19, 2013.
- 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.