Pressure gradient control system
CA 2073136 C · Owner: Taikisha, Ltd. · Inventors: Matsui, Yoshiaki; Moriwaki, Mutsumi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A pressure gradient control system includes a ventilated area divided unto a plurality of intercommunicating zones, a zone-to-zone pressure gradient detecting device for detecting pressure gradients between adjacent zones, a control unit for adjusting quantities of air supply or exhaust to/from the zones based on detection information received from the zone-to-zone pressure gradient detecting device to establish a predetermined pressure gradient between adjacent zones, and an interior-ambient pressure gradient detecting device for detecting pressure gradients between an ambient area and those of the zones communicating with the ambient area. The control unit is operable, in response to …
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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 July 3, 1992 and granted September 21, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 3, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 3, 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.