Low noise charging system
CA 2210551 C · Owner: Wong, Chee-Chiu Joseph · Inventors: Fournia, Peter G.; Wong, Chee-Chiu Joseph
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus for achieving optimum noise control of multiple coronode wires in a copier/printer involves optimizing phase relationships of the voltage on the wires in such a way so as to steer the maximum part of the noise distribution profile in the direction best suited for absorption or dissipation. In a two corotron charging system, the coronodes are preferably charged to where the phase angle, charge frequency and spacing between wires are optimized.
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 July 16, 1997 and granted May 15, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 16, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 16, 2019.
- 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.