System for driving drum
CA 1283442 C · Owner: Nakamura, Thutomu · Inventors: Ohishi, Tetsuo; Fukuyama, Norio; Kyutoku, Senzo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A system for driving a drum includes a pulse motor including an annular rotor fixedly mounted within the drum for rotation therewith and rotatable relative to a stator disposed within the rotor. The pitches of the rotor teeth and stator teeth are determined in such a manner that a magnetic flux linking each of the coils is changed in a sinusoidal fashion in synchronism with the rotation of the rotor. A pole position-detecting device produces a multi-phase sinusoidal pole position-detecting signal representative of the position of the magnetic poles relative to the rotor. A speed control device produces a current amplitude command signal representative of a desired torque of the rotor. A …
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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 April 23, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 23, 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.