Switch mechanism with two fulcrums
CA 2074287 C · Owner: Pdl Holdings Limited · Inventors: Cook, David Langman
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A switch mechanism opens a contact set in the event of an undervoltage condition. The mechanism involves a lever assembly biased by a spring for pivoting about one or other of two fulcrums to open or close the contacts respectively. The undervoltage causes a solenoid to release a plunger which initiates operation about a fixed fulcrum. A reset device is used manually to initiate operation about a movable fulcrum, provided that the voltage is sufficient. An arm is deflected by the plunger to shift the movable fulcrum and also acts to restore the plunger daring reset. The switch mechanism may be incorporated in a residual current device which provides the undervoltage condition on detecting …
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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 July 21, 1992 and granted August 17, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 21, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 21, 2014.
- 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.