Improved means of controlling a vacuum cleaner employing a separate suction and brush motor
CA 2383445 A1 · Owner: Conrad, Wayne Ernest · Inventors: Conrad, Wayne Ernest
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus is provided which uses a plurality of batteries that are sequentially used to power an appliance. While one or more batteries are used to power the appliance, one or more batteries are charged for subsequent use. The rate of charge of the batteries is comparable to the rate of discharge of the batteries by the appliance or faster. Thus the appliance may be essentially continuously used by the user removing the discharged battery and inserting a charged battery.
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 April 25, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 25, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 25, 2024.
- 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.