Circuit breaker
CA 2268575 C · Owner: Max Leader Limited · Inventors: Lam, Sheir Chun
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A circuit breaker (10) for use in a power/load circuit formed by a three-phase AC power supply (11) and a load (12) connected to the power supply (11) by means of three live power lines (R-R', S-S' & T-T'). The circuit breaker (10) comprises a tripping circuit (60) including switches (SW1) connected in series with the respective power lines facing the power supply (11), a transformer (T1) having at least three balanced primary windings (P1 to P3) connected subsequently in series along the respective power lines and a secondary winding (S1), and a voltage comparator (50) connected to the secondary winding (S1) for comparing a voltage induced in the transformer (T1) with a reference voltage …
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 6, 1999 and granted December 2, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 6, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 6, 2021.
- 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.