Electrical heating apparatus with overheating protection
CA 1138509 A · Owner: Fieldcrest Mills, Inc. · Inventors: Mills, Edwin R.; Elmore, Ernest L.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure, An electrical heating apparatus and par-, ticularly a bedcover preferably in the form of a blanket protected against an overheating condition and in which electrical current flow through a heating element is controlled by a pair of gate controlled bidirectional semiconductor switches electrically connected to one another in series and in front-to-front orientation. The gates of the semiconductor switches are connected through a temperature sensitive capacitor which triggers the semiconductor switches from a conductive to a nonconductive state in response to the sensing of an overheating condition.
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
- Granted December 28, 1982. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 28, 1999.
- 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.