Fail-safe surge arrester
CA 2012253 C · Owner: Johnson, Stephen Paul · Inventors: Woodworth, Jonathan Jay; Miller, David Richard; Johnson, Stephen Paul
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A fail-safe, non-fragmenting surge arrester includes a liner having outlets formed in the walls thereof for venting ionized gases generated within the liner by internal arcing. The vented ionized gas forms a lower impedance path for the current which is thereby shunted around the failed internal components preventing the generation of internal pressure which could otherwise cause a fragmenting failure mode of the arrester. The internal components include stacked varistor elements and may include an internal fuse link electrically in series with the varistors.
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 March 15, 1990 and granted October 6, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 15, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 15, 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.