Glass melting
CA 2018740 C · Owner: Pilkington Plc · Inventors: Whitfield, Peter James; Trevelyan, Robert Emmett
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A glass melting tank has a melting chamber a shallow uniflow, conditioning chamber a shallow refining chamber and a riser chamber between the melting chamber and refining chamber. Heat is input to glass in the riser chamber by electrodes located centrally in the riser chamber near the base of the riser chamber. Temperature sensors sense the temperature entering the riser chamber through a throat and near the base of a downstream wall of the riser chamber and the heat input is controlled to produce torroidal flow in the riser chamber.
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 June 11, 1990 and granted March 30, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 11, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 11, 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.