Method and apparatus for controlling a fume hood
CA 2116134 C · Owner: Sharp, Gordon P. · Inventors: Sharp, Gordon P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to a fume hood controlling method and apparatus which reduces the amount of replacement air required to operate a fume hood (10) by permitting the fume hood to operate at a relatively low face velocity in the absence of a containment affecting condition, but which is capable of detecting the occurrence of a containment affecting condition such as, the presence or movement (34) of a user within a selected area of the face of the fume hood, and of increasing face velocity to a selected level in response to such detection. When the detected condition no longer exists, the control automatically returns the fume hood to the lower face velocity, preferably with a time …
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 August 17, 1992 and granted October 5, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 17, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 17, 2014.
- 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.