Liquid heating apparatus
CA 2092934 C · Owner: Maruyama, Noboru · Inventors: Maruyama, Noboru
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a liquid heating apparatus according to the present invention, an internal drum is arranged at a space from and in an external drum, a combustion gas descending chamber is provided therebetween, an outer water chamber having a hot water outlet port and a water supply port in the upper and lower sections thereof is provided outside the combustion gas descending chamber, an inner water chamber communicating with communicating tubes in the upper and lower sections to the outer water chamber is provided inside the combustion gas descending chamber, a combustion chamber communicating to the combustion gas descending chamber in the upper section is provided inside the internal drum, and …
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 30, 1993 and granted November 20, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 30, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 30, 2015.
- 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.