Method of operation of air cleaner
CA 2018282 C · Owner: Matsushita Electric Industrial Co. Ltd. · Inventors: Abe, Shuji; Hayashi, Nobuhiro
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of operation of an air cleaner comprises the steps of: detecting a concentration of a given gas by a gas sensor when a command signal for turning off the gas sensor is present; storing the concentration; turning off the gas sensor; detecting the concentration of the given gas by the gas sensor when a command signal for turning on the gas sensor is present; determining a reference value by choosing either the stored concentration or the concentration detected after the gas sensor is turned on which is lower than the other, at an instant that a predetermined interval has passed after the gas sensor is turned on; and controlling a blower motor of the air cleaner in accordance with …
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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 June 5, 1990 and granted December 30, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 5, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 5, 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.