Active sound and/or vibration control
CA 2049332 C · Owner: Topexpress Limited · Inventors: Eatwell, Graham Paul; Dorling, Christopher Mark; Hodson, William Richard
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An active sound or vibration control system for compensating noise or vibration arising from a periodic source of changing periodicity, wherein sensors (6) sense the existing noise and vibration the sensor signals, are sampled several times per cycle by an ADC (8) triggered by a signal output from a sensor (3) detecting the position of the source in its cycle the sampled , signals are transformed into compensation actuator drive signal values by a series of transform and adaptation modules (11 to 13, 15) based on algorithms dependent on the frequency of the source, and the drive signal values are stored in a memory means (1) continually updated by the values derived from the sampled …
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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 April 20, 1990 and granted August 1, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 20, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 20, 2012.
- 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.