Thermionic emitter and method of manufacture thereof
CA 2014139 C · Owner: Carrico, John Paul, Jr. · Inventors: Spangler, Glenn Edward; Campbell, Donald Noble; Carrico, John Paul, Jr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A thermionic emitter for providing positive ions incorporates a mixture of beta-alumina and inert material, such as charcoal, positioned on a filament for heating the mixture. Alternately, the invention may incorporate beta-alumina with inert material such, as nickle, deposited in selected areas. As a result the thermionic emitter overcomes the problem of generating positive ions with low power consumption.
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 9, 1990 and granted October 16, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 9, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 9, 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.