Cryogenic cold shelf
CA 2219967 C · Owner: Devack, Donald Leonard · Inventors: Devack, Donald Leonard; Cheng, Alan Tat Yan
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A cryogenic cold shelf for use in a freeze drying system having a cryogen distributor for passing cryogenic fluid into the shelf volume of the cold shelf at differing rates so as to even refrigeration provided over the entire shelf resulting in a uniform temperature over the cold shelf.
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 November 3, 1997 and granted April 3, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 3, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 3, 2019.
- 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.