Three wire, three phase, heating cable and system
CA 2192875 C · Owner: Sperika Enterprises Ltd. · Inventors: Wildi, Theodore
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An electrical three-phase heating cable and system that produces a reduced magnetic field and which uses a cable containing three insulated copper wires, or equivalents, as heating elements. The wires are equidistantly spaced from each other, in triangular configuration the, geometric center of the triangle coinciding with the longitudinal axis of the cable. The wires are twisted in a uniform fashion along the longitudinal axis of the cable. Its low operating temperature robustness, and safety enable the system to be installed for example, in floors and, walls for the general heating of buildings and in outdoor pavements, for, snow-melting purposes etc. The feeder conductors are also …
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 December 13, 1996 and granted January 2, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 13, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 13, 2018.
- 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.