Process gas distribution system and method
CA 2050247 C · Owner: Sci Systems, Inc. · Inventors: Geist, Stephen G.; Hayes, Gregory L.; Sierk, Dennis A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A plurality of gas flow control units in cabinets are connected to distribute process gas, on demand, to a plurality of utilization locations known as "tool" locations in a semi-conductor manufacturing plant. Each gas flow control unit is connected to a single tool interface controller over a single communications cable. The status and operational characteristics of the individual units are communicated through the tool interface controller to a supervisory control computer by means of polling. Each flow control cabinet has its own data processor, and can be operated alone. Also the supervisory computer, can be used to operate each cabinet as well as to monitor operations of the system. Gas …
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 29, 1991 and granted January 7, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 29, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 29, 2013.
- 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.